Downloaded From: www.bhawesh.com.np # DATA COLLECTION Collection of data is the first and most important statistical investigation. The process of collection necessary information from the field of enquiry by the investigators themselves or by their agents is called data collection. If the collected data are reliable, then the decision will be correct. Otherwise, the results will be misleading and may be harmful also. # SOURCES OF DATA On the basis of sources of data, there are two types of data: Primary data: The data: The data which are collected by an investigator originally from it's basic source for the first time for any statistical enquiry are known as primary data. The primary data are also called first hand data. As it is collected directly from the informants. Primary data are generally used in those cases where the secondary data do not provide an adequate basis for analysis. Primary data are also called field source. Example: Data obtained in a population census by C.B.S (Central Bureau of statistics) are primary data of same organization. Secondary data: Those data which are collected by one agency organization or person but used by other agency, organization or person is called secondary data. These types of data are not original for the user. These are also called second hand data. The data which are already collected by someone but obtained from some published and unpublished sources are called secondary data. Example: For Central Bureau of statistics, the census data are primary whereas for the all others we use, such data are secondary. # DIFFERENCES BETWEEN PRIMARY AND SECONDARY DATA. Primary data Secondary data Data collected first time from the field of • Data that are already collected and used by • study are called primary data. others are called secondary data. They are first hand or original in nature. They are second hand in nature. • • It gives more accurate information. Sometimes secondary data may not be • accurate. They are like raw materials and they have to • They are found in ready-made form just like • be processed after collection. finished goods. •
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Collection of primary data takes a large amount of money and efforts.
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Secondary data save money, time and efforts, because these are used from the existing sources.
There is no need to worry about while using • Secondary data should be carefully and critically primary data by the investigator. examined before they are used. # METHOD OF COLLECTION OF PRIMARY DATA There are various methods of collecting primary data which are as follows: 1. Direct Personal Interview: In this method, the investigator or his agent collects the data by asking the questions individually. There is face to face contact between the respondence and the interviewer. This method is suitable: When the area of inquiry is limited. When the data is to be kept secret. Merits: The data obtained by this method are pure and original in character. The investigator can clarify any doubts during the interview. Demerits: This method takes a lot of time so, it is expensive method. There is chance of getting biased information. Indirect Personal Interview: In this method, the investigator does not directly ask the questions to the persons who are directly concerned with the problem. The investigator obtains the necessary information by contacting the third person who is familiar with the problem. The third person is said witness. This method is suitable: When the direct sources of information are not available. When the informants are unwilling to give the correct information. Merits: It can cover a wider area very easily. This method is cheaper, requires less time, money and labour Demerits: The witness may be biased to provide accurate information. The selected informants may not be appropriate people to answer the questions. •
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Downloaded From: www.bhawesh.com.np 3. Information from Corresponds. In this method, the investigator appoints local agents or correspondence in different parts or field of enquiry to collect information. These corresponds collected and send to the central office. This method is suitable for: Newspaper agencies, televisions agency for regular information. Merits: The information through this method is accurate. This method is cheaper and less time consuming. Demerits: Information sent by agents may not be reliable. It is difficult to check the accuracy of the data. 4. Mail Questionnaire. In this method, the investigator prepares a questionnaire (a set of questions). The questionnaire is sent to the various informants by post of mail. They are requested to answer the questions and post back to the indicator. This method is suitable: When the field of investigation is large. When the investigator requires quick result at low cost. Merits: This method is cheaper, saves time and labour. The information can be collected from very far areas. Demerits: There is high degree of non-response error. Informants may feel fear to provide information. 5. Schedule sent through Enumerator. In this method, the enumerators go to the informants personally with the schedule (a list of questions) and fill off the list of questions in their own handwriting by interviewing the informants. Population census in Nepal is conducted by this method. This met hod is suitable: When the informants are illiterate Merits: The results obtained by this method are reliable and accurate. Some additional information can also be obtained. Demerits: This method is more expensive. The enumerators should be well trained, skilled and tactful. Otherwise, data may not be correct. # PROBLEMS IN PRIMARY DATA COLLECTION. The informants may be uneducated and uncooperative. Thus, the relevant and accurate information may not be collected. If there is no transportation facility, the investigator may take the information without interviewing the informants. The real facts of the data are not available due to the different conclusions given by the different informants about the same topic. The limitation of time and money is the other problem involved in primary data collection. Only few questionnaires are send back to the investigators by informants while using mail questionnaire method. So, accurate data can't be expected. Due to the shame, hesitate, fear of respondence, the investigator may not be collected reliable information. # SOURCES OF SECONDARY DATA. Secondary data can be obtained from two sources. They are: Published sources. Published can be categorized in to following chart: 2. Unpublished sources: All information may not be published but they may be suitable for the purpose of investigation. The sources of unpublished data are: Reports of private office. Hospital records. Records of VDCs. Records of schools and campus administration Thesis, field reports etc. of University students. # PROBLEMS IN SECONDARY DATA COLLECTION. •
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Downloaded From: www.bhawesh.com.np Necessary information may not be published during the period of investigation. The data obtained from secondary sources may not be suitable for the further research study. The data obtained from secondary source may not be adequate for the purpose of finding the solution of research problems. The data obtained from secondary sources may not be reliable due to the limitations of primary data. # PRECAUTIONS IN THE USE OF SECONDARY DATA. Secondary data are collected by someone and used by others. So, the investigators should check about the reliability, suitability and adequacy before using secondary data. It is because the secondary data may be inadequate and unsuitable. Thus, following precautions should be adapted while using secondary data 1. Reliability of secondary data. The success or failure of any research work depends on reliability of data. If the collected data are accurate and reliable then the results becomes right and such type of investigation shows reality. If the collected data are wrong or insufficient, the result becomes wrong and the consequences become harmful. Thus, before using secondary data, we should check whether the data are reliable or not. While testing the reliability, the following things should be take n into consideration. Who collected the data, what were the objectives of collecting data? Was the investigator experienced, capable, hone st, and unbiased? Whether the appropriate techniques of collecting data were applied or not? What degree of accuracy was maintained in the data? Was there checking about the accuracy of data? In which time period and in what sort of conditions were the data collected? Suitability. While using secondary data, we have to examine thoroughly, whether the data are suitable for our investigation or not. The suitability of the data can be tested by comparing the nature, objectives and scope of the present enquiry with those of the original enquiry. If the nature of the data is different, such data will not be suitable for the study and can't be valid result. 3. Adequacy. Though the availability of data is suitable, it may not be adequate for enquiry. Data must cover the study area. Otherwise, the findings can't be generalized. For example: if we want to investigate about the success rate of grade 11 students of the Jhapa, the data from only Damak can't be adequate. Instead, we should also collect the data from other places. # TECHNIQUES METHODS OF DATA COLLECTION. There are two types of techniques of data collection: 1. Census: A census is a technique of data collection where the information is collected from each and every unit of the population associated with the subject matter of enquiry. In Nepal, census occurs every ten years. In such census information about each and every individual of the country is collected. Not a single individual is left out in such a census. Merits: It gives complete information about the population. This method is more suitable for limited area. Demerits: It is more expensive, labour requiring and time consuming. This method is impossible if the population size is infinite. 2. Sampling method: In this method, only the part of population units is selected as a representative of the whole population. The selected part of the units is called sample and the method of selecting sample is called sample method. The number of items in the sample is known as sample size. For example: 15 people are drawn from a population of 250 people of a village to know the drinking habits of those 15 people are the sample for the study. Merits: This method is less time consuming, less labour requiring and cheaper. In case of infinite population, it is the suitable method. Demerits: The sample units may not represent the population. Due to the biasness of the indicator, the result obtained may be misleading. • • •
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