CONTENTS OF ENTIRE BOOK
Unit 1 Markets: How They Work.......................................................................................... 1 Positive and normative thinking ................................................................................................1 Opportunity cost ........................................................................................................................1 The production frontier or production possibility curve ............................................................3 Specialisation and foreign fore ign trade.................................................................................................. trade..................................................................................................6 6 Demand and supply: an introduction..........................................................................................8 The elasticity elast icity of demand.............................................. demand...................................................................................... .............................................................20 .....................20 The elasticity elast icity of supply............................................ supply................................................................................. .................................................................30 ............................30 Demand and supply: applications to any market are possible..................................................32 The market mar ket mechanism working......................................... working...................................................................... ......................................................34 .........................34 Consumer and producer surplus...............................................................................................39 Unit 2 Markets : Why Markets Markets Can Fail................................................. Fail.............................................................................43 ............................43 What does market failure mean?..............................................................................................44 Reason 1 - Monopoly elements or market dominance.............................................................47 Oligopoly..................................................................................................................................51 Imperfect competition or monopolistic competition................................................................54 Reason 2 - externalities, social cost and private costs..............................................................58 Reason 3 - public goods................................................... goods...................................................................................... .........................................................64 ......................64 Reason 4 - merit goods.............................................................................................................65 Reason 5 - demerit goods.........................................................................................................66 Reason 6 - information failures................................................................................................67 Reason 8 - factor immobility....................................................................................................70 Other issues and market problems exist: The distribution of income and wealth....................................................................................75 Economies of scale...................................................................................................................79 Price fixing by government or one of its bodies.......................................................................84 Unit 3: Managing the Economy................... Economy............................................................... ..........................................................................90 ..............................90 Why is the government involved in the economy....................................................................90 How can government try to manage the economy?..................................................................92 Inflation......................................................................... Inflation............................................ .......................................................... ........................................................... ...............................95 .95 Unemployment.......................................................................................................................100 The balance of payments........................................................................................................106 Gross domestic do mestic product produ ct (GDP)............................................................................................... (GDP)...............................................................................................110 110 Economic growth................................................ growth....................................................................................... ....................................................................113 .............................113 Aggregate demand.................................................................... demand..................................................................................................................120 ..............................................120 Aggregate supply.............................................................. supply....................................................................................................................122 ......................................................122 Altering the level of national income.....................................................................................123 Macroeconomic policy – what the government does or tries to do........................................128 The multiplier.........................................................................................................................136 The interest rate and the level of investment..........................................................................136 Money and monetary policy...................................................................................................138 Fiscal policy.............................................. policy..................................................................................... .............................................................................. .......................................146 146 Supply side economics...........................................................................................................152 The Phillips Phillip s curve..................................................... curv e............................................................................................................. ..............................................................158 ......158 Unit 4: “The Theory of Production & Costs”....................................................................164 The growth of firms................................................................................................................164 firms................................................................................................................164 The external growth of firms:.................................................................................................167 Multination corporations.................................................... corporations................................................................................. .....................................................169 ........................169
An introduction to production theory and costs......................................................................170 Cost curves...................................... curves................................................................... ........................................................... ...........................................................175 .............................175 The different possible market conditions................................................................................178 Perfect competition............................................................................... competition.................................................................................................................179 ..................................179 Monopoly............................................................................ Monopoly............................................ ................................................................. ....................................................184 ...................184 Imperfect competition or monopolistic competition..............................................................188 An introduction introduc tion to efficiency........................................................ efficiency..................................................................................................192 ..........................................192 An introduction to price discrimination..................................................................................196 Pricing strategies................................................. strategies...................................................................................... ....................................................................199 ...............................199 Game theory................................... theory................................................................. ............................................................ ...........................................................201 .............................201 Oligopoly - the kinked demand curve......................... curve ...................................................... .......................................................... ...............................203 ..203
Unit 5A: Labour Markets....................................................................................................207 Markets....................................................................................................207 The supply supp ly of labour.............................................................. labour.............................................................................................................. .................................................207 .207 The demand d emand for labour.......................................... labour.......................................................................... ............................................................... ..................................210 ...210 Determining the equilibrium wage.........................................................................................214 The effects effec ts of trade unions..................................... u nions.................................................................. .......................................................... ....................................217 .......217 Differences in earnings...........................................................................................................222 Labour participation, unemployment and ageing...................................................................229 An introduction to the distribution of income and wealth......................................................233 Unit 6, The UK in the Global Economy: “Globalisation and Protection”.......................236 An introduction to globalisation and protection.....................................................................236 Trade protection and trade liberalisation................................................................................238 Trading blocs and the world trade organisation (WTO).........................................................242 The balance of payments........................................................................................................247 The European monetary union (EMU)...................................................................................255 Public expenditure in the UK......................... UK...................................................... ......................................................... ............................................258 ................258 Inward foreign investment by multinational corporations......................................................264 External shocks and the global economy................................................................................266
Module2881TheMarketSystem,Unit1: Module2881TheMarketSy stem,Unit1: “Markets:HowTheyWork”
ThecourseistheGCEAdvancedLevelinEconomics,followingtheEdexcelsyllabus but if you are followingadifferentsyllabusthenyoucansimply selectthepartsofthisbookthat you can use. Economics is economics! TheGCEAlevelisnormallytakenintheUKin the Sixth Form (grades 11 and 12) and it is most commonlyusedforselectingstudents foruniversityentrance. This is a series of teaching notes I used until I stopped teaching recently. If you spot any errors, please email me and let me know. I maintain a few email addresses for different purposes; currently they are:
[email protected] and
[email protected]. If you receive no reply it may mean that somewhere along the line a spam trap has nabbed your message. You can try sending it again, but try taking out any words that you thing a spam trap might not like. An alternative explanation is that Hotmail thought it was spam and deleted it after a few days when I was on holiday or something and was not checking my junk mail box regularly. Converting my files to PDF format resulted in the occasional strange error appearing. I corrected all that I noticed but if I missed any and you spot them, please email me! Now down to business. If you want good marks, these notes should be read and reread until you really know them. Practise drawing the diagrams until you can do them from memory without making mistakes. It is a good idea to revise something and practise drawing diagrams for a short period every day.
1-1.INTRODUCTION POSITIVEANDNORMATIVETHINKING
Positive economics deals with what is; normative thinking deals with what ought to be and is value-laden. All sciences and fields of learning try to be positive and deal with facts and models based on facts. You should try to be positive i.e. scientific in your statements, especially when writing essays and in the exam room. Words like "ought", or "should" or “as a nation we must” are all normative statements and you should do your best to avoid them. Try not to say things like “It would be better if…”,or “the government should….” “it would be a good thing for X to do Y”. Many policy prescriptions you might wish to make are normative, e.g., “The economy would be better off if we….” and it can raise an examiner’s hackles. You might get away with a general statement such as “Some advocate…”, “It has been suggested that…” or “Many believe that….” as these are positive statements and sound less normative. Note that the words used in an otherwise scientific study can themselves carry a normative feeling, e.g. "freedom", "democracy", "efficiency", or "welfare" may all seem to be “good words to many people; whereas words such as “inequitable”, “exploitation”,"unsound", "interference","fascist",or"police state"seem"bad"tomanypeople.
OPPORTUNITYCOST
We live in a world of scarcity, in the sense that we can never have everything that we might like. As a result we must make choices, for instance whether to buy this or that, whether to eat this or that, whether to walk in the park or go to a movie, or whether to produce this or that. Every time we make a choice to do something we automatically exclude something else that we did not do we have given it up. We call this the “opportunity cost”.
Definition “Opportunity cost is the best forgone alternative” i.e. it is what we gave up to get what we did. The opportunity cost of buying new pair of shoes might be a lunch forgone. 1
· ·
The opportunity cost of buying a new shirt might be not going to the cinema. The opportunity cost of taking a part-time job might be not being able to hang out in the mall with your friends.
For a producer The opportunity cost of buying plastic packaging material might be the cardboard he did not buy. NB there can be many alternatives foregone, but only one will be the opportunity cost you cannot add them up and say they are all the opportunity cost, because it must be a choice between them. Opportunity cost can be thought of as: 1. The cost in pounds (represents a real thing given up); or 2. The cost in time. Opportunity cost is important 1. We use it whenever we are deciding what to do, for example shall we hire a couple of videos or buy a pizza instead. 2. It always arises with budget allocations. At some point in your life you may have to draw up a budget and allocate money for different purposes. You will be forced to weigh up what is really needed in your tennis club, computer society, your country or whatever. 3. It lies behind the cost curves that we draw. How does this work? Consider two producers, A and B. Producer A might have to pay £20 a ton to get the iron ore to make into motor cars. Producer A sees the cost as £20, but we see it as the way of making sure he gets the resources, rather than letting B get them! So the opportunity cost really does stand behind the cost curves we draw. Similarly in consumption: if something costs £10, you have to pay £10 to buy it. That £10 is not only the price of the object, it is also the amount you have to pay to get the resources, raw materials, labour etc. that went into making it. This prevented these resources from going into making something else. After you buy the item it will be reordered by the shopkeeper and replaced on the shelf. S/he orders from a wholesaler who in turn orders more from the producer. The producer then buys the raw materials etc. to make another of whatever you bought! In this way, resources keep on going into making whatever people demand. 4. This is how the price mechanism really works – that is, how it allocates resources to wherever the demand is the greatest.
2
THE PRODUCTION FRONTIER OR PRODUCTION POSSIBILITY CURVE What is it? It shows us the maximum that a country can produce. There is clearly a limit to this at any one time just like there is a limit to the weight that you can lift over your head or eat at any time. We assume two goods (I will use apples and bananas as these easily can be represented by A and B) for ease of explanation – but it is true of any number of goods.
Drawing the diagram – we start with the maximum amount of good A we can produce if all our resources are devoted to producing A which gives us a point on the vertical axis; then we do the same for the case if we only produce B to give us a point on the horizontal axis. Then we join the two positions with a straight line. Once we have drawn the line, we do not have to have all apples or all bananas but we can chose somewhere along it. Any point on it represents a mix of the two goods that people wish to buy. At the point selected above, people consume 0A1 apples and 0B1 Bananas.
Apples
A1 PPC1
0
Bananas B1
[DIGRESSION: DRAWING THE CURVES You should practise drawing all the diagrams regularly – several times each day is a good idea. In the end, they need to be second nature to you so that you can recall and correctly draw the appropriate diagram whenever you want. It is most important to be able to this so that you can quickly gain good marks. The wrong diagram, a mislabelled mislabelled one, or one lacking lacking labels, labels, more more or less dooms dooms you to fail. fail. It shows shows that you do not really understand what you are saying and examiners hate that. Labels, by the way, are the words on the diagram, like “apples”, “bananas” or “ppc 1” in this diagram.
When tutoring, I would draw each diagram again in front of the student, and explain the importance of getting it right (and remind them of this now and then later). It is important to see how a diagram is built up as they are really easy to do, but to be suddenly presented with a complicated finished product can be a bit daunting. For this reason, I have put in a sensible order of drawing the diagram for the first few times I present them. It is just about impossible to get a good mark in economics without drawing diagrams, so start practicing without delay! Warning! It may seem easy, but it helps you much less if you download diagrams from the Internet and paste them into essays. It is more valuable for you to draw them, and learn them, for yourself. END OF DIGRESSION] 3
The way the diagram of the production possibility curve is drawn.
Apples
Apples
Apples
A1 PPC1
0
0
Bananas
PPC1
Bananas
0
B1
Bananas
We usually draw the production function curved , to reflect the law of diminishing returns. Some factors of production are better at producing A and not as good at B, as you might imagine. Some land is simply better at growing bananas than apples, just as some of your friends are better at doing maths, swimming or playing the guitar than others. So as we move down the production possibility curve and get more bananas, we can expect to get a few less bananas than we might expect; perhaps we used to give up 5 apples to get 5 more bananas, but as we slide down the curve we will get, say, only 4 more bananas, then only 3 more, or 2 more, as we keep sliding down. The line curves in at each end to show this as in the diagram below.
Apples A A2
A1
0
PPC
Equilibrium point where ppc is just tangent to the price line AB
B1 B2
B Bananas
[Digression . It is unlikely in my view that you will be asked why the production frontier is curved as op[Digression. posed to a straight line, but if you do, the reasoning above and the diagram explains it. In the diagram you can easily see that if we had a straight line production possibility curve (like AB) we could produce the maximum amount of apples at the end of it, that is, at A, and have no bananas at all. But as diminishing returns do exist, we are actually on the curved A2B2. The maximum apples possible are at A2 (not A which we could reach if we were on the straight line ppc ). As diminishing returns put us on the curve not the straight, the difference between A2 and A is the quantity of apples lost because of diminishing returns, End of digres sion]
It is common to use straight line production frontiers in text books because they are easier to draw and manipulate, so they often look like the diagram below. 4
Apples
A1 PPC1
Bananas
0
B1
What happens if we swivel swivel the curve? If society learns learns to get better at producing Apples Apples alone, it would swivel the curve out along the vertical axis of apples. This reflects the fact that we can get more output from the resources and factors of production that we have. The swivel that gives us more apples reflects a productivity increase in apples, but not in bananas.
Apples A2
A1
0
B
Bananas
After the productivity increase in the apple growing industry, withe same quantity and quality of factors of production, society can increase the output of apples from 0A1 to 0A2, that is, by the distance A1 to A2.
If we swivel it the other way, and push out B , we would get a productivity increase in bananas, but not in apples. What if we move the whole curve out? If a country has learned to get better at producing everything, this would physically move the production frontier upwards and outward, which is economic growth.
5
Apples A
A2 A1
ppc1 = now
0
ppc2 = 4 years time
B Bananas
B1B2
We return to the subject of economic growth in the unit “Managing the economy”.
SPECIALISATION AND FOREIGN TRADE
If people specialise they are more productive – if you are like me, you probably could not make a good pair of shoes, do brain surgery or advise on investing for pensions! We tend to do what we are best at. Imagine the result if we did what we are worst at! Countries are the same – if they concentrate on what they are best at, they produce more and better goods or services. As a rule of thumb, countries that follow a protectionist policy (protecting their industries from foreign competition) are trying to do what they are worst at, or at least not trying to do what they could be best at. Most economists would probably think that protectionism is not exactly a good idea. Two concepts of “advantage” Absolute advantage – this means a country can produce more of almost everything than another, i.e., it is a wealthy country. The USA can produce more than Egypt for instance – clearly, the USA has an absolute advantage over Egypt. It is of no particular interest as an idea: the rich are just rich! Comparative advantage – this means that a country is better at producing something, but not necessarily everything, than another. For instance, Sweden is better at making marine engines than the UK, but we are better at organising financial markets and insurance. All countries are better at doing a few things more than others.
Comparative advantage is the one that matters in economics and it is the main reason why countries trade with each other. We do not simply buy pineapples from tropical countries because it is too cold to grow them here. We could in fact grow them under glass and with heating, but we clearly lack a comparative advantage in the pineapple producing business. Hawaii on the other hand has a strong comparative advantage in that area.
The gains from trade If a country tries to produce everything for itself, it will stay poor. Examples: China under Mao Zedong and Russia under Stalin both followed such a policy and the people suffered a very low standard of living as a result. The message is that trade helps the people in a country to gain wealth! 6
The gains from trade consist of: ·
·
·
Comparative advantage – we do what we are best at and thus produce more. We then exchange our surplus with other countries for something we we are less good at. Both the other countries and our country do better and enjoy higher living standards as a result. Economies of scale – if we specialise we can follow a system of mass production, and lower our costs. We can then exchange the surplus with other countries. Economies of scale are examined in Unit 2. We can gain wider consumer choice e.g., we can drive Volvos, Renaults or BMW’s, as well well as locally-made Fords!
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1-2. DEMAND AND SUPPLY: INTRODUCTION
(Abbreviations: S = “supply”; D = “demand”; Y = “income”; r = “rate of interest”) At the equilibrium price, the quantity demanded just equals the quantity supplied. There are unsatisfied consumers who could not buy at that price even though they were willing. What do we mean by equilibrium? Equilibrium is the state of affairs in which there is no tendency to change. How do we show this equilibrium price? We use demand and supply curves.
Demand What is the demand curve? It is a curve showing the quantity that will be bought on the market at different prices. The lower the price, the more will be demanded; the higher the price the less will be demanded. Think! If all Nike trainers were £2 a pair, would you buy more than if they were £200 a pair? It seems probable!
Price
So the demand curve is drawn sloping downward, left to right. Examine the one here - at a high price, high up on the price axis, little is demanded as we trace a line down to the quantity axis. But at a lower price, a greater quantity is demanded.
D
Quantity
0
In economics, “demand” means demand is backed by money – it is not just a need or a desire, but people do have the money to buy and are prepared to buy.
Supply What is the supply curve? The supply curve is a curve showing the quantity that will be offered on the market at different prices. We believe that higher prices cause more people to sell. Imagine: in your classroom, if I offer to buy each T shirt for £500, almost everyone will sell to me; but if I offer £1 each, probably few if any would be willing If however I were to offer £7, more would sell but probably not everyone. That is why the supply curve slopes upward.
8
Price S
Quantity
0 Let’s put both the demand and supply curves on the same diagram .
Price D
S
P
0
Quantity
Q
Guess where the equilibrium price will be? Right! Where the two curves cross! As said earlier, at the equilibrium price, the quantity demanded just equals the quantity supplied. There are no unsatisfied consumers who could not buy at that price even though they were willing and everyone who wanted to sell at that price could do so. This happy situation happens at the intersection of D and S with price P and quantity Q. When I started in economics, I had to chant along with the rest of the class: "price is determined by supply and demand!” It certainly made it stick in my mind and might help you too!
Let us return return and look at demand in more detail (We’ll look at supply later too) 9
What determines the D curve? i.e., why is it where it is and not somewhere else? Price
D here?
Or why not here?
D
D Quantity
0
1. There are four main personal determinants of demand · · · ·
Income Taste Prices of other goods or service Expectations about future prices of this good or service
2. AND several other market determinants ·
·
·
·
·
Income distribution - if you think of all the other people in your house and you as you are now, then if you suddenly got all the total income and savings and the others had none, there would be a different pattern of demand from what it is now. They probably do not eat lunch every day if they have no money. It is the same in society in general: change the income distribution and a new pattern of demand curves follows. Wealth distribution (as opposed to income distribution). If 10% of the population have 90% of the wealth, probably more Porsche motor cars will be demanded than if we all have the same rather lowish amount! Population size - the larger the population, the bigger the demand, ceteris paribus . That is a LatLatin tag meaning “all other things remaining the same” and you might come across it in a lot of economics books. Population age distribution - if there are many old people, important demands in society will be for medicines, hip replacement operations and Zimmer frames but fewer Beastie Boys CDs, or prams. The interest rate. This is especially important for house purchases, motor cars, long-life consumer goods often on a credit card, or hire purchase generally. A higher rate of interest means more to re pay, so people tend to borrow less.
What can cause a shift in the demand curve? (= a new curve) 10
A change in any of the above determinants of demand will do it! If demand increases, overall, more of the good/service is bought at any unchanged (the same) price. You can see this in the diagram below, where at P1 an amount OQ1 is demanded, but after demand increases to D2, at the same price an large amount is demanded, i.e., OQ2. It is easy to remember what “an increase in demand” means; there must be a new curve and it will move upwards and to the right. Price D1
D2
P
Quantity
0
Q1
Q2
The effects of an increase in demand are usually analysed using the equilibrium positions determined by the intersection of demand and supply.
Price D1
D2
S
P2 P1
0
Quantity Q1 Q2
You can see that the increase in demand means we move from the equilibrium position P1Q1 to the new equilibrium position P2Q2. More is demanded - we shift from the position Q1 to the position Q2, so the difference (OQ2 minus OQ1) is Q1Q2.
11
The way the diagram of a shift in demand is drawn,(shown d rawn,(shown not moving to the new equilibrium, so you can see that more is demanded at the same price) Price
Price
Price
Price
S1
S1
P1
D1
P1
D1
Quantity
S1
D1
Quantity
Q1
Quantity
D1 D2 Q1
Q2 Quantity
The way the diagrams are built up should be reasonably clear by now. If you have any worries, check back and examine those supplied earlier. The general principles are:
1. Draw the axes and label them immediately (“one axis, two axes”). 2. Put in the first curve and label it. 3. Add the second curve and label it. 4. Draw the equilibrium position – preferably using dotted lines. 5. Make the necessary changes, such as shift a curve inwards or outwards by drawing a new curve and labelling it. 6. Draw the new equilibrium position – preferably using dotted lines. 7. And finally you compare the new equilibrium position with the first one, using your own words but trying to get in the necessary jargon phrases such as “increase in demand”, or “economic growth”, whatever is relevant to the question you are tackling. Henceforth I shall not be supplying the series of pictures showing how the diagrams are built up, as you should be able to follow the above principles for yourself. Before long, it will become second nature to examine a finished diagram and work out how it was built up.
If demand decreases , the demand curve shifts the other way, downward and to the left. Again we have a new curve, as in the diagram below. Price D2
D1
P
0
Quantity Q2
Q1
You will notice that less is bought at any given price, such as P. 12
Again, a decrease in demand is usually analysed by determining the new equilibrium position and the com paring it with the original one. For this we need to put the supply curve in.
Price D2
D1
S
P1 P2
Quantity
0
Q2 Q1
As you can see, if demand decreases, then less is bought (as you might imagine!) and the quantity demanded falls from Q2 to Q1; price also falls, in this case from P1 to P2
Let us look at supply in more detail
What determines the supply curve, i.e. why is it where it is and not somewhere else?
Price S??
S??
Quantity
0
The answer is, the price, p rice, quantity, q uantity, and quality of inputs used. These consist of things th ings like machinery, equipment, staff and workers, raw materials, and fuel. These are collectively known as “the factors of production”, and are often summarised as land, (L) labour (N) and capital (K) plus a remainder term, R. 13
·
Land - is what it says but can include things like diamonds or oil that are found there.
·
Labour mostly means workers, but also includes managers.
·
Capital means machinery and equipment. A subset of this is“social overhead capital” - like roads, bridges and docks.
[Digression: The The whole production production of the nation can can be summed up as: O = f(L, N, K) + R or put into words, “output is a function of (= is in some as yet undefined way caused by) land, labour, capital, and a few other things”. You will need this later; I am just sowing a few seeds.] ·
The remainder term “R”, which covers things in both labour and capital is the really interesting one
The labour component of “R”. This consists of things like entrepreneurial ability, the managerial methods in use, labour motivation and how good it is, labour skills, the strength of the trade union and its attitudes, the bonus and other incentive systems in force, the quality of the education system, and the retraining facilities available in society. The capital component of “R”. This consists of things like: The level of technology, knowledge about what technology is available, the adequacy of factory organisation, and economies of scale. They can obviously affect the supply curve, or the output possible, if they are good or bad. ·
·
·
Maybe the th e weather, weather , e.g. floods can destroy d estroy crops, c rops, effect transport, reduce supply, and raise price. Joint supply - if we increase the number of sheep to supply an increased demand for mutton, it automatically increases the wool supply. So the price of related good can be a determinant of supply. Examiners like questions on joint supply, but it is not often encountered in the world in which we live. The productivity of the factors of production – this is closely related to technology; but it can also be how hard workers are prepared to work, motivation, and incentives systems etc. (it too can appear separately, or be included in the remainder term, R, as above).
·
The size and number nu mber of firms in the industry, including inclu ding the marketing marketi ng conditions.
·
War and social unrest.
What can cause an increase or decrease in supply?(a shift in the curve)
Like demand, it needs a change in one or more of the determinants. For supply these include things like: A change in the price of a factor of production. A change in the productivity of a factor. New technology invented. The discovery of a new raw material or fuel. More worker enthusiasm. This occurs often in war time, because of patriotism. · · · · ·
An increase in supply = the curve shifts downward and to the right (more is supplied at the unchanged price) - e.g., if labour productivity increases or someone finds a new cheap source of materials. 14
Price S1 S1
S2 S2
P1
0
Q1
Quantity
Q2
You will notice that the quantity supplied at the unchanged price P1 increases - well, that’s what an increase in supply does! And if we put in a demand curve we can see both the equilibrium positions and work out that an increase in supply means a fall in price and an increase in the quantity purchased. Price S1 S1
S2 S2
P1 P2
D
0
Quantity Q1 Q2
15
A decrease in supply is the opposite; the supply curve shifts up and to the left: Price S1 S1
S2 S2
P1
0
Q2
Quantity
Q1
Again, less is supplied at any chosen price; we move from a supply of OQ1 to the smaller quantity OQ2.
The new and old equilibrium positions need both a supply curve and a demand curve. Price S2 S2
S1 S1
P2 P1
D
0
Quantity Q2 Q1
More analysis! A decrease in supply means a fall in the quantity supplied and an increase in price. Work out for yourself the old and new quantities and prices - good practice!
16
Time Periods And Supply
Three time periods matter: · · ·
the very short run (VSR) (or “momentary supply”), the short run (SR) , and the long run (LR).
They have different slopes to their curves and different elasticities (more later!). The very short run. This is defined as the time when no change can be made in any of the factors of production – the supply curve is vertical. Examples are the fruit and vegetables that appear in the wholesale market each day. The short run. This is defined as the period in which the variable factors can be altered but not the fixed factors, i.e. we can make some changes. ·
·
Fixed factors = those that do not vary with output such as factory building, transport fleet, office staff, and the bill for heating and lighting the premises. Variable factors = those that vary directly with output such as raw materials, the energy used, the petrol in the trucks, and the wages of some unskilled workers who might be taken on when needed, perhaps part-time.
The supply curve we usually draw is the short run one. The long run Is defined as the period when all factors can be varied i.e., the producer can do any changes s/he wants. This means a flatter curve, possibly even downward sloping sometimes.
How the supply curve can vary with the time period we are considering: The flatter the curve, the more elastic it is (“quantity stretches more”). Producers will only make changes that help them produce more or reduce costs.
Price S very short run totally inelastic
S short run fairly inelastic S short run close to unit inelastic
S long run high elasticity Falling long run S curve (modern hi tech goods for example get cheaper over time)
Quantity
0 17
NOTE that all the curves are drawn on the one diagram; this means the scale is the same for all; if you draw each in a separate diagram, the flatter one (S long run) is not necessarily the most elastic, as the horizontal axis might be on a much wider scale. If this seems incomprehensibl incomprehensiblee to you, Do Not Not Worry! Just remember to put them all on the same diagram. Remember that you should practise drawing the diagrams regularly!
Increases and Extensions of Supply And Demand
We know that the word "increase" means a shift of the curve – but what about extensions? "Extensions" are movements along an existing curve. Questions are often set to see if you know the difference between an ”increase” and an “extension”.
[A digression: if a line crosses two others, an increase in one curve always means an extension of the other! The diagram here shows that.
We see two upward sloping lines that cross a single line. The upward sloping lines reflect an increase (or decrease) and we slide down (or up) the single line.
For supply and demand: With an increase in demand we slide up an unchanged supply curve. Price S1 The shift of D1 to D2 is an increase in demand
P2 P1
The sliding up the unchanged S curve is an extension of supply
D1 Q1 Q2
D2
Quantity 18
It’s clear that an increase in demand goes with an extension of supply.
NOTE that we start on demand deman d curve curv e D1 and supply s upply curve cu rve S1 to ascertain asce rtain the th e equilibrium price and quantity; then we look at D2 to get the second equilibrium position. Reminder: In economics, at this level we always start in equilibrium, then we alter something, and move to the new equilibrium position. We then compare the two equilibrium positions for the analysis.
And we can see an increase in supply goes with an extension of demand, as we slide down an unchanged demand curve:
With an increase in supply we slide down an unchanged demand curve Price S1 S1
P1
S2 S2
The shift of S1 to S2 is an increase in supply
Sliding down the unchanged D curve is an extension of demand
P2
D
0
Quantity S1 S2
Decreases and contractions contractions of supply and demand
A decrease means a new curve, which shifts backwards; a contraction means sliding back along an unchanged curve. A contraction of demand following a decrease in supply : Price S2 S2
P2
S1 S1
The shift of S1 to S2 is a decrease in supply
Sliding up the unchanged D curve is a contraction of demand
P1
D
0
Quantity S2 S1
19
A contraction of supply following a decrease in demand Price S
The shift of D1 to D2 is | a decrease in demand
P1 Sliding down the unchanged S cuve is a contraction of supply
P2
D1 D2
0
Quantity S1 S2
Here is one of the the hoary old trick trick questions. questions. "Demand increases, so price rises. The rise in price means fewer can afford the good, so demand decreases and prices fall again." Do you agree with this statement?
Question: what do you think?
At first glance it might seem to make sense. sense. But it is in fact false! Why is it false? You draw the diagram now on a piece of paper. First increase the demand curve and you will see the price rise as we extend up the supply curve. Then think about the new equilibrium. Why on earth should it change? It is an equilibrium position! That was why you learned the definition of equilibrium a little while ago - to be able to detect fallacies in argument. This is a proposition in logic, designed to test if you really understand supply and demand. You should try to get the words “extension” “extensio n” and “increase” in to show sho w you can use them properly and you you definitely need a diagram.
1-4. THE CONCEPT OF ELASTICITY: MEASURING MEASURING THE RESPONSIVENESS OF DEMAND AND SUPPLY (very popular with examiners)
ELASTICITIES
Elasticities are a sort of measure of supply and demand. If demand increases, and we ask how much does supply extend, we need more than an answer like "quite a lot"!! Government may be trying to raise tax to get a certain amount of revenue for instance. The question is “How much will quantity change, a lot or a little?” 20
WE START WITH THE ELASTICITY OF DEMAND
Three broad types of elasticity of demand
1. Price elasticity = the usual one, it deals with 1 good. 2. Cross elasticity = a special one, it deals with 2 goods. 3. Income elasticity elasticity = a special one and it deals with changes changes in incomes incomes..
1. Price Elasticity of Demand
Definition : "Price elasticity of demand is a measure of the responsiv Definition: responsiveness eness of the quantity demanded to a small change in in price". Learn this by heart! heart! [In simpler terms, “is the proportional change in quantity greater or lesser than the change in price?” As an example, if the price was 20 and it falls by 2, the fall is 10% (2 times 100, all divided by 20); and if quantity then increases from 100 to 200, the increase is 100%. We can see that the increase in Q is greater (100% compared with 10%) - i.e., it stretches stretches out a lot - it is elastic!]
How do we actually measure price elasticity?
Price elasticity of demand is measured by the percentage change chan ge in Qd, divided by the percentage change in price: %∆Qd %∆P
So the price elasticity of demand is: ∆Q
Q -----------∆P P = ∆Q x ∆P Q
= ∆Q x Q ∆P P
(to divide by fraction invert and multiply) P
(gathering the change terms all on side for neatness. If this shuffling makes you unhappy, just remember that 3 x 4 is the same as 4 x 3)
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In the example above, the percentage change in Q was 100 and the percentage change in price was 10 so the elasticity is 100 divided by 10 = 10.0 In the world in which we live this is actually very high! (Anything over 2 in the real world is pretty high.) Logically the answer can have only on ly 1 of 3 results: <1, = 1, 1, or >1 >1 (< stands for “less than”; > stands for “more than”; if we are looking at “<” left to right, the way we read, we see it goes little to big so it is easy to remember!) When we look at the fraction, we find that the answer is less than 1 if the top is smaller than the bottom, equal to 1 if the top and bottom are the same, or more than 1 if the top is greater than the bottom. What does each possible answer mean? a] If the answer is greater than 1 (e.g., 1.62) the demand curve is elastic.
means that It means that a small change in price led to big change in quantity (Q stretched a lot which means it is elastic); graphically the curve tends to look flat when compared with an inelastic curve. But remember all curves must have the same scale and axis or else be on the same diagram. Examples of demand curves which are price elastic: Dell computers (one brand of many substitutes); foreign travel by cheap airlines.
b] If the answer is less than 1, e.g., 0.75, the demand curve is inelastic People do not respond so much to price cuts and although althoug h they buy more, they do not buy a lot more. Examples: Salt, bread, sets of cutlery (essentials; no substitutes).
c] If the answer just happens to equal 1 it is “unit elastic” (unity = 1), a special case and rarely seen, except perhaps for a small small part of a large demand curve! The answer would would work out at exactly 1.0 and the curve is asymptotic; this means that it approaches more and more closely but never quite reaches the axes.
Reminder: if you draw one rather flat demand curve in one diagram, demand Reminder: demand is actually actu ally only e tc because we do not know know the scale - don’t worry about it, it’s technical! t echnical! relatively elastic etc Just remember to say “relatively inelastic” or “relatively elastic” in the exam room! If you draw them on on one diagram then you are on safer ground if you just say “elastic”. What do the different elasticity demand curves look like? Price
Elastic D
[The unit elastic demand is not drawn well - I am a rotten artist I fear.]
Inelastic D
Unit elastic D (not well drawn!)
Quantity
0 22
The importance of the elasticity concept
It allows us to get precise answers, not be vague. We need it for certain questions e.g., if a hairdresser is considering increasing her price for a basic cut from from £20 to £25, will profits rise or fall? What determines price elasticity? ·
·
·
·
The number of substitutes - the greater the substitutes, the more elastic the good - a small price rise means consumers switch to another brand. THIS IS THE MAIN DETERMINAN DETERMINANT! T! The proportion of income - the greater the proportion of income going on good, the more elastic it tends to be. Salt is relatively inelastic and very cheap - would you consume a £2’s worth a year? Luxuries and necessities - luxuries tend to be more elastic (airfares, foreign travel); necessities necessities more inelastic (electricity). Some economists do not like this “luxuries” point because what constitutes a luxury alters too much and in addition they can be personal to different individuals. Time - the longer the time, the more elastic demand tends to be, probably because ·
· ·
More substitutes become available , the good or service is copied by others, new manufacturers can enter, imports be made etc. Habits change only slowly, so we adjust to new prices slowly. Capital may need to wear out to make change, e.g., if the price of petrol rises, drivers have to wait until it is time to buy a new and smaller car in order to reduce petrol consumption.
Q. For the hairdresser earlier who is considering consid ering a price rise, I asked earlier what would happen h appen to her profit if she charged more. Assume she is very good and her clients feel that there is no real substitute? substitute? A. The demand curve for her services is inelastic so profit would rise! Q. But consider what would happen if she were just another high street hair dresser? Draw the diagram for me now!
Another example of the importance of elasticity: if the government raises the tax on cigarettes, will government revenue revenue rise or fall? And by how much?
The government normally wishes to raise more revenue - although there are health benefits if people reduce cigarette consumption, which saves on National Health Service expenditure too. If the government raises tax by 5% and demand is inelastic, the quantity will fall as price rises, but it will fall by less than 5%, so revenue will increase. If the government imposes an indirect tax, it pushes up the supply curve by the exact amount of tax. If the tax is absolute e.g., £1 each item, it pushes the curve up parallel. The original producer faces no change in supply conditions, but £1 is added to each quantity.
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When we draw the diagram for the imposition of indirect tax: we start at the original equilibrium, and add the tax. Price S1 S1
S2 S2
P2 P1
Quantity
0
Q1
When we look at the market equilibrium, we start with a supply and demand curve and see the original equilibrium. We then add the tax, which pushes up the supply curve and look at the new equilibrium position, to see what changes the tax has made. Price S1 S1
S2 S2
Note that that the supplier works on the original S1 curve - the S2 curve merely includes the government tax.
P2 P1
D
Quantity
0
Q2 Q1
We can see that the original equilibrium position P1Q1 becomes P2Q2 P2Q2 once the tax is imposed. There is a rise in price - but by less than the whole tax - and there is a fall in quantity. Price S2 S2
P2 P1
S1 S1
C B A D
0
Quantity Q2 Q1
The increase in tax per unit is AC, but the price only goes from P1 to P2 = BC; and BC is less than AC (price rises but by less than the whole amount of tax per unit) 24
What about the change in government revenue? This is the quantity now sold (OQ2 at the new equilibrium position = the number of units) times the tax per unit (AC). This is the area bounded by P2CAP3 in the diagram below. Price S1 S1
S2 S2
C
P2 P1
B
P3
A D
Quantity
0
Q2 Q1
If the indirect tax is ad valorem (proportional not absolute, ab solute, e.g., 10%) it pushes up the supply curve at an increasing rate
Q. Why? A. Because 10% of £1 is only 10P, but 10% of £10 is £1!
Price S2
[Not very well drawn = my inadequacy as an artist]
S1 P2 P1
C B
A D
0
Quantity Q2 Q1
25
Price S2 S2
P2 P1
S1 S1
C B A D
0
Quantity Q2 Q1
The government revenue is the quantity now sold (OQ2 at the new equilibrium position = the number of units) times the tax per unit (AC). This is the area bounded by P2CAP3.
If the indirect tax is ad valorem (proportional not absolute, ab solute, e.g., 10%) it pushes up the supply curve at an increasing rate
Q. Why? A. Because 10% of £1 is only 10P, but 10% of £10 is £1! Price S2
S1 P2 P1
C B
A D
0
Quantity Q2 Q1
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A subsidy is just a negative tax e.g., government gives producer some money (subsidy) rather than a producer or consumer giving money to the government (tax).
Subsidy questions are not usually as interesting as tax ones! Let’s draw the diagram for putting on a subsidy.
Price S1 S1
S2 S2
P1
P2 D
Quantity
0
Q1
We start, as ever, in the initial equilibrium position, P1Q1 on the curves S1 and D1. The subsidy goes on, the size of it is P1 to P2, and the new supply curve is S2. You can see that the unchanged quantity, Q1, is now cheaper at price P2- but we have not yet examined the new equilibrium position to see the results of the change.
What is the total amount of the subsidy, i.e., the cost to the government? We need to look at the new equilibrium position, which will be at P2Q2, below. Price S1 S1
S2 S2
A P1 P2 B D
0
Quantity Q1 Q2 27
The subsidy is AB for each unit in the diagram above. The quantity sold after the subsidy is imposed is OQ2. So how much does the subsidy cost the government, and ultimately the tax payer? Price S1 S1
S2 S2
D
P3 A P1 P2
C B D
Quantity
0
Q1 Q2
The subsidy the government pays is the new quantity sold, (0Q2) times the subsidy amount per unit of BA. We know that BA is the same as CD because the curve shifts parallel. We know that the suppliers continue with curve S1, so they require price 0P3 for quantity 0Q2 (Note that the supplier works off the original supply curve - there has been no change in the determinants of his or her supply.) We see that consumers pay the rectangle 0Q2CP2. We see that the government pays the rectangle P2CDP3 - this is the subsidy cost to the tax payer. And together these add up to the total expenditure of 0Q2DP3. Notice also that consumption rises from 0Q1 to 0Q2 - which is the point of the subsidy: more is produced and consumed.
The limits of price elasticity of demand
Perfectly elastic = a horizontal line; this means that consumers will demand an infinite amount at that price! It is merely a limit and obviously it cannot be reached. Perfectly inelastic = vertical line; this thi s means that consumers will pay any amount amou nt at all, such as £1, or £1 £1 million, or £1 trillion…. to buy the good or service. Again this is unreasonable, it’s merely merely a limit. limit. They look like this: Price Perfectly inelastic demand
Perfectly elastic demand
Quantity
0 28
2. Cross Elasticity of Demand
Definition: "Cross elasticity of demand is a measure of the responsiveness of the quantity demanded of one good or service to a small change in price of another". Learn this! It is virtually the same as the definition of price elasticity earlier - go on, compare them now! Cross elasticity measures substitutes and complements (note the spelling; it is not “compl “compliment iments”) s”) If the supply of beef increases so the equilibrium price falls, it may induce some people to switch from eating chicken or pork to eating the now cheaper beef. The fall in price of beef causes a decrease decrease in quantity demanded of chicken or pork. %∆Qd of good A %∆P of good B Note the “A” and “B” difference: we are dividing the percentage change in the quantity of A by the change in the price of B. If the price of beef fell and the quantity of chicken fell the answer will will be positive, because two negatives make a positive, so any items with a positive cross elasticity are substitutes. If the price of heating oil falls it may induce some to install oil generated central heating in houses. We see that a fall in the price of A means an increase in the quantity of generators, so the answer is negative (one plus and one minus) so these two goods are complements. Cross elasticity does not seem to be used much in economics, except in exams.
3. Income Elasticity of Demand
Now this is most important! Incomes keep increasing over time, so the demand pattern for various goods and services keeps changing. This matters for new firms firms looking to move into the market and produce something: the market for what goods or services is likely to grow the fastest? That’s the area to be in! It matters for existing firms looking to diversify, or be concerned about the prospects for the future in the area they produce and sell in. Definition: "Income elasticity of demand is a measure of the responsiveness of the quantity demanded of a good or service to a small change in income". Learn! Income elastic: a given change in income leads to a greater than proportionate increase in demand for the good or service. Examples of income elastic goods: foreign travel, good wines, wines, smart motor cars, eating in restaurants, and currently well-regarded brands, e.g., Adidas sportswear or Rolex watches. Income inelastic: inelastic: a given change in in income leads to a less than proportionate proportionate increase increase in demand demand for the good or service. Examples: bread, staple foods generally, cheap stores, and all lowly-regarded lowly-regarded brands. If our income happens to double doub le (lucky us!) we do not spend twice as much on such items. Income neutral elastic: should it just happen that, say, a 5% increase in income leads to a 5% increase in demand for a good or service, then it is income neutral elastic. This is not really an interesting case, merely a bit strange. Oddly enough, Pizza Hut in Australia claimed in the 1990s that they were like this: in a recession some people stopped eating out so stopped going to Pizza Hut, but other people switched from “proper” restaurants to Pizza Hut which cancelled things out, so the company did not suffer! Income negative Income negative elastic: elastic: this is most most interesti interesting! ng! This happens when an increase in income causes a fall in demand. Really it indicates that we dislike this product but for some reason we must consume it at the time. When we can afford not to consume it, then we stop buying it. Examiners like this concept! 29
Examples are scarce, but it is suggested that probably potatoes were like this in Ireland during the Nineteenth century. Currently, the demand for mealies (sweet corn) in some African countries may be income negative neg ative elastic. el astic. It is a rare r are event even t anyway. Negative Negative income elasticity elasticity means means that it is an “inferior “inferior good”.
THE ELASTICITY OF SUPPLY Definition: the responsiveness of the quantity supplied to a small change in price. It is measured by: %∆Qs %∆P The measure roughly indicates the slope of the supply curve; the steeper the more inelastic. Why is this only “roughly”? Because it depends on the scale of the diagram - for instance both the diagrams below have the same elasticity, but because the horizontal scale is not the same the slopes look different. That is why we have to draw two different elasticities elasticities on the same diagram where the scale is the same. Price
x
Price
S
x
x
x l
1
S
l
l
2
3
l
4
l
5
Quantity
0
l
l
l
l
l
l
l
1 2 34 5
l
l
Quantity
l l
l
BUT unit elastic elastic supply is any straight line that cuts through through the origin! (Just remember remember this, and do not worry! If you are a mathematician mathematician,, you may already see why.) Price
S
S
Quantity
0 30
Supply periods and time: (covered briefly earlier)
Price S very short run totally inelastic
S short run fairly inelastic S short run close to unit inelastic
S long run high elasticity Falling long run S curve (modern hi tech goods for example get cheaper over time)
Quantity
0
Very short run = totally inelastic supply = fixed supply (e.g., the amount in a wholesale vegetable market delivered each morning; all the works of dead painters or sculptors). Short run = perhaps moderately inelastic. Long run = more elastic; or even negative elasticity (it slopes downward).
Why is supply more elastic in the long run?
Because the company can alter both the fixed and variable factors (i.e., all the factors of production). It can also find new or cheaper sources of raw materials; improve the training of labour; and introduce new technology or better machines. This allows the company to obtain more output without needing much increase in price. The downward sloping supply curve in the long run is already familiar to you: computers, scanners, TV sets, digital cameras, DVD players and discs, CD players and discs….. Most if not all of the products of modern hi-tech industry fall into this category. As the years go by, they get better and a lot cheaper. Elasticity of supply is probably a bit less interesting to economists than the elasticities of demand - and it is easier to learn as there is less of o f it!
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1-5. DEMAND AND SUPPLY: APPLICATIONS TO ANY MARKET MARKET ARE POSSIBLE
Popular ones that examiners often like to set a question about include: Housing Foreign exchange Agricultural products or raw material production, like tin or coal (often inelastic S and D so fluctuations are common) · · ·
But the analysis is virtually identical in each case! You need to mention supply and demand very early in your answer and then use supply and demand analysis, drawing the curves you need. Be prepared to handle: · · · · · · · · ·
The concept of equilibrium The determinants of supply and of demand An increase in demand and a decrease in demand An increase in supply and a decrease in supply An extension of both demand and supply The elasticity of demand and supply Minimum price fixing (examined in Unit 2) Maximum price fixing (examined in Unit 2) Applying an indirect tax (which shifts S curve up and to right).
An example of foreign exchange
You must use use a diagram diagram or two! two! The value of a currency is determined by the supply and demand for it - just like any other good or service, it is the normal equilibrium diagram you need. The supply of £’s comes from the UK importing goods and services from abroad. We pay in pounds to a bank, which uses them to buy the US $ etc. that we need to pay the foreign supplier. If we import imp ort more, we increase the supply of pounds on the market, thus putting pressure on the pound to fall in value. Similarly, if we export, we buy the pounds back, thereby increasing the demand for pounds. You could usefully practice drawing diagrams to fit these scenarios. They are the standard increase in supply and decrease in supply diagrams, but with “Quantity of £” on the horizontal axis and “Price “Price of £ in $” on the vertical one. We have to value the pound in some other currency, such as US$. Value of the pound in $ S1
($)P1
D1 0
Q1 Quantity of pounds in international markets 32
If the UK increases its imports, this puts more pounds on the international markets as we pay for the extra imports. This means an increase in the balance of trade deficit. This increase in supply then puts pressure on the value of the pound, which falls.
Value of the pound in $ S1
S2
($)P1 ($)P2 D1 0
Q1 Q2 Quantity of pounds in international markets
If foreign holders of pounds, largely banks but also others such as large international companies as well as international speculators, decide the pound is overvalued and about to fall, they might sell. The results are the same: the increase in supply reduces the value of the pound. This may be termed “self justifying expectations”. An example of the labour market.
If the UK allows more migrants in, this increases the supply of labour. Because many migrants are relatively young males, they add to the supply of labour, normally producing more than they take out in social security benefits. The increase in the supply of labour puts pressure on to lower wages, especially for the unskilled or semi-skilled. It is difficult difficult for many migrants to find more professional work unless their English is good; they tend to end up in the unskilled sector, even if they have skills and abilities, abilities, until their lanlanguage skill improves sufficiently and this can take many months or years. The result is the normal diagram for an increase in supply, in this case of labour. You need the quantity of labour on the horizontal axis and wages on the vertical. Go on, draw it now! now!
Remember! You must use diagrams to answer questions about price or wages. Many markers glance at the diagrams first and if they are correct, he or she is immediately disposed to give you a good mark and a decent pass! If your diagrams are clear and correct, correct, they might also give you the benefit of the doubt if they have trouble with your handwriting handwriting or standard of grammatical English. In the exam room in economics it is virtually impossible impossible to get a good mark without diagrams.
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1-6 LET’S RECAP AND SHOW THE MARKET MECHANISM WORKING IN ALL ITS GLORY IN A PERFECT WORLD
In a perfect world, a market system will give a perfect result - resources will be allocated exactly to where people need them to produce what the people demand. Think supply and demand curves for two goods, both in equilibrium; assume people spend all their money (as this is easier to imagine how it works). Then increase the demand for one good (whi ch means you must reduce demand for the other, because they are spending all their money by assumption). First we look at the goods market - let’s assume they are bread and milk; we start in equilibrium, then we will increase the demand for one good and see what happens. Secondly, we examine the factor market which lies below the goods market. That consists of those resources that are used to produce the bread and milk. We use the labour labo ur market as the factor of production. We have simplified the model by using two goods and one factor to show the perfect workings of the market. With any number of goods and services and more factors we can still get this perfect resource allocation. (The whole of Unit One in this course is devoted to this market solution. Unit Two will explain why we may not in fact attain this theoretical perfection.) Abbreviations used: MC = marginal cost AC = average cost P = price Q = quantity MR = marginal revenue Lab = labour AR = average revenue PPC = production possibility curve (production frontier)
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We start with the market for goods or services (bread and milk) in equilibrium
Bread
Milk
Price
Price D
S
D
P
S
P
0
Quantity
Q
0
Quantity
Q
And we can also examine the factor market for these goods; in this case we will use the people who make thee bread and produce the milk (Unit 4 covers labour markets in detail). Again we start in equilibrium. th (The two diagrams below do not have to look exactly the same as the two above; they just have to be normal supply and demand curves.) Bread workers
Milk workers
Wage
Wage D
S
W
W
0
D
S
Qlab
0
Quantity of la labou bour r
35
Qlab
Quantity of la labo bour ur
THEN, WE CHANGE SOMETHING AND ALTER THE EQUILIBRIUM POSITIONS
let’s increase the demand for bread and reduce the demand for milk. (On the assumption that all income is spent, if people spend more on bread they must spend less on milk.) We start as usual in equilibrium, on the demand curve for bread, “D1” and increase it to “D2”. People switch to consuming more bread and away from milk, so the demand for milk falls, from D1 to D2. Bread
Milk
Price D1
Price
D2 S
D1
S
D2 P2 P1
P1 P2
Q1 Q2
0
Quantity 0
Q2
Quantity
Q1
You can see on the left that the price of bread rises (people demand it more) and on the right the price of milk falls (less demand). Because of this change in the demand pattern, we get an increase in the demand d emand for workers to produce more bread and a fall in the demand for milk workers - and we will reach a new equilibrium in the factor market. Again, demand increases from “D” to “D1” for the bread workers, and falls from “D” to “D1” for the milk workers. Bread workers
Milk workers
Wage
Wage D1
D2
S
S
D1 D2
W2 W1
W1
W2
0
Qlab1Qlab2
0
Quantity of la labo bour ur
Qlab2 Qlab1
Quantity of la labo bour ur
You can see on the right that wages rise where demand for the product has increased (bread), and on the left they fall where the product is less in demand than previously (milk). (milk). 36
We can put changes in goods/services market and factor markets together into one diagram, one directly above the other and read it vertically v ertically to see what happens to the factors of production produ ction in both industries as demand changes. Milk
Bread Price
Price D1
D2
D1
S
S
D2 P2 P1
P1
P2
Quantity
Q1 Q2
0
0
Q2
Bread workers
Quantity
Q1
Milk workers
Wage
Wage D1
D2
S
S
D1 D2
W2 W1
W1
Trace the lines down from the equilibrium positions in the goods market to the corre sponding equilibrium in the labour market for the workers needed to produce the quantity in the top diagrams
W2
0
Qlab1Qlab2
Quantity of lab labour our
0
Qlab2 Qlab1
Quantity of labo labour ur
We see, as the demand for a good or service increases (top left hand side), this sucks factors into that industry - but where do they come from? They come from the contracting industry, where the demand for a good or service has decreased (top right hand side) - the factors of production (land, capital and workers) have to leave that industry (in the real world, if unemployment already existed, some of the unemployed might be drawn into work). Where demand for a good or service falls, the workers might simply be dismissed - which really annoys people, upsets the trade unions, and might have a political fallout with loss of support for the government. Or the firms may take advantage of “natural wastage”; that is to say that is to say, as people voluntarily leave, they are not replaced.
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Who leaves? Several groups may be involved: · · · ·
· ·
old workers who are retiring because of age those who get ill and retire those resigning and moving to a better job as part of a career move those who move to a new area of the country, following their spouse, to get to a better climate or school area for instance those who migrate to a different country those who die
Unemployed people are naturally very upset and social problems can emerge which the government may have to deal with. But with capital, e.g., trucks, or warehousing facilities, shifting the use of these causes little upset - things have no feelings! They may be sold or leased to other companies companies to use. Land is similar to capital, it can often be transferred to several other uses fairly easily.
The above diagrams of resources moving from declining sectors to expanding ones and stopping in equilibrium demonstrate the way the market mechanism (price mechanism) operates.
This was first spotted by Adam Smith in the Wealth of Nations as early as 1776 although the diagrams did not come until later. Understanding how an economic system works in this fashion led to the phrase “the consumer is king” as the next sentence explains. Resources (land, labour and capital) flow from where they are not in demand, or demand is falling, to where they are in demand, or demand is rising. So the price mechanism is well-regarded as a good (but by no means perfect) way of allocating resources to society’s demands. Later, in Unit 2 “Why markets fail” you will learn what can, and actually does, go wrong with this apparently brilliant market system.
A reminder: are you revising something and practising drawing a few diagrams each day ?
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1-7 CONSUMER AND PRODUCER SURPLUS
We know that there is an equilibrium market price at which both consumers buy and suppliers sell. But what about the consumers and producers who are not themselves exactly at that equilibrium price? They receive a benefit. For consumers, we can see from the demand curve that the first consumer, buying at 1 on the quantity axis, would be willing to pay P1, which is much more than the market price he or she has h as to pay (P mkt). So the column above P mkt is a sort of surplus that the first buyer enjoys!
Price P1
D This triangle is the consumer surplus
P mkt
0
Quantity
Q
123
Similarly, for the second buyer, at 2 on the quantity axis; and the same goes for the third and subsequent buyers until we get out to Q1 and P Mkt. Mkt. All these early consumers would pay more but do not have to do so - and they gain a lot of extra enjoyment as a result. Eventually the whole triangle above P Mkt is filled in; and an d the filled in bit of this triangle, indicated by an arrow, is the consumer surplus. For producers, we have an analogous argument. Some would be willing to supply more cheaply than the equilibrium price, P Mkt. In the diagram below, we can see from the supply curve that the supplier of the first unit would be happy to do this at a price well below P Mkt. The column above quantity 1 up to P Mkt is again a sort of extra or surplus - which in this case belonging to the producers. Moving to quantity 2, again we can see a column, but a bit smaller than for quantity 1. And as we move out towards Q1, the triangle above the supply curve but below P Mkt is filled in. The arrow again points to it. This is “the producers’ surplus”.
Price This triangle is the produce surplus
S
P mkt
P1 0 123
Quantity
Q1 39
If we put the two diagrams together, we can see that both the triangles thus make up the total consumer surplus and the producer surplus.
Price S This triangle is the consumer surplus P mkt This triangle is the producer prod ucer surplus D
P1 0 123
Quantity
Q1
Use of the concept
With indirect taxation, the imposition of a tax (or if there already is such a tax, an increase or decrease in such a tax) may impinge more on consumers than producers - or vice versa! “Who gains the most (or who loses the most)?” is the question. This may be called “the incidence of taxation”, “the tax burden”, or a question may be asked, such as “who bears the brunt of the tax?” The answer as to who gains or loses the most depends on the elasticities involved. Let us assume that an indirect tax on a good increases. If demand is highly inelastic (consumers (consumers will pay almost any high price without reducing consumption much) then the increase must largely fall on these consumers - they are simply willing to pay! We know they are prepared to do so because the demand curve is relatively inelastic and that is what inelastic demand means. Cigarettes probably probabl y fall into this category, as do all addictive drugs. Think of a vertical demand curve: if we increase the tax, the supply curve just moves up; there is no change in the quantity demanded; suppliers still receive the old price (reading off their supply curve S1; the gap between S1 and S2 is all tax and goes to the government not to the supplier). There is clearly no loss of producer surplus as their situation has not changed at all - and consumers pay all the difference: Price Perfectly inelastic dem demand and
S2 P2
S1
P1
0
Quantity 40
It can be proved, but you can take it on trust, that if the elasticity of demand is lower than the elasticity elasticity of supply, the consumer loses more than the supplier! In other words, it is the relative elasticities that count. The usual supply and demand situation divides the incidence of tax (who pays it, or more of it) between suppliers and consumers - and of course the incidence falls heavier on the side which is relatively inelastic. You may get a question about the incidence of tax - or one about imposing (or increasing) an indirect indirect tax. A reminder: in introductory economics we nearly always use “static equilibrium analysis” which means we start in equilibrium, change something, and analyse the result.
Who then bears the burden of tax when an indirect tax increases? See the diagram below. below. Price
Demand S2 P2 P1
B S1
A
C D
0
Quantity Q2
Q1
We start on the curves S1 and Demand, with the equilibrium price P1 and quantity Q1. Then we add a tax (or increase an existing tax!) which shifts the supply curve up to S2, by the amount of the tax. Any tax per unit shifts the supply curve curv e up vertically; the tax is the line BD in the diagram above. Having made our change, we look at the result: consumers pay BC of the tax, and producers pay CD of it. The distance CD is smaller than the distance BC, the consumer pays more of the tax, and we also know that the elasticity of supply must be greater than the elasticity of demand! We can also look at the areas and see the changes in both surpluses: The consumer surplus reduces by ABC. The producer surplus reduces by ACD. In Unit 4, “Industrial economics”, we again use the concept of surpluses in our monopoly diagram. We can show the deadweight loss of monopoly, as well as the loss of consumer surplus and the increase in the producer surplus that results from the monopolist being able to set the quantity that he or she produces which results in the most profitable price possible. possible. More of this later!
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