The HIPO (Hierarchy plus Input-Process-Output) technique is a tool for planning and/or documenting a computer program. A HIPO model consists of a hier...
• Developed by IBM as a tool and documentation technique which attempts to: – Provide a structure by which the function of a system can be understood. – State the functions to be accomplished. – Provide a visual description of the input, process and output for each function.
Purpose: • to define procedures and operations in a hierarchical manner, correlating input, processing, and output steps with the integrated whole expressed in the hierarchy diagram.
• A HIPO package consists of a hierarchy chart and IPO overview diagram and IPO detail diagram: Hierarchy Chart acts as a hierarchical chart for the function performed by the system. IPO overview diagram – shows a general sequence of inputs, major processing functions, and outputs. IPO Detailed Diagram – shows a detailed sequence of inputs, shows a detailed sequence of inputs, major processing functions, and outputs.
HIPO Diagram
IPO overview diagram
IPO Detailed Diagram
Ishikawa Diagram • also known as Fishbone Diagram, Cause and Effect Diagram or Root Cause Analysis. • is a tool used for systematically identifying and presenting all the possible causes of a particular problem in graphical format. The possible causes are presented at various levels of detail in connected branches, with the level of detail increasing as the branch goes outward, i.e., an outer branch is a cause of the inner branch it is attached to. Thus, the outermost branches usually indicate the root causes of the problem.
• The Ishikawa Diagram resembles a fishbone (hence the alternative name "Fishbone Diagram") - it has a box (the 'fish head') that contains the statement of the problem at one end of the diagram. From this box originates the main branch (the 'fish spine') of the diagram. Sticking out of this main branch are major branches that categorize the causes according to their nature.
• How to Construct: 1.Place the main problem under investigation in a box on the right. 2.Have the team generate and clarify all the potential sources of variation. 3.Use an affinity diagram to sort the process variables into naturally related groups. The labels of these groups are the names for the major bones on the Ishikawa diagram. 4.Place the process variables on the appropriate bones of the Ishikawa diagram. 5.Combine each bone in turn, insuring that the process variables are specific, measurable, and controllable.
