Data Collection

The first state of the PSM is analysis where an organisation and its systems are examined to determine the nature of the problem to be solved. At the end of analysis, a logical design can be drawn up which sets out the feature set of the finished system.

Data Collection To collect information, different methods may be used. Not all methods are appropriate to all information. Empirical information (fact-based information derived from experimentation or observation rather than theory) is the strongest form in many cases. This involves measuring, timing, counting, adding up, averaging etc - all fact-based rather than opinion-based subjective information.

Data Collection Methods Surveys and Questionnaires – Survey customers, Questionnaires from workers Interviews and Focus Groups – Interview manager to determine scope, constraint, requirements of the projects Observations – People working or using the system Document Reviews – Records, budgets, log etc..

Examples Use a stopwatch to time how long it takes a program to print 10,000 invoices. - Observation Scan an error log to count how many breakdowns a system had last month. – Documentation Review Summarise financial records over the past year to add up the total cost of ownership of a communications system. Add up the total amount of time a worker spent being productive in an 8 hour shift instead of working around system faults. Where possible, collect empirical evidence when at all possible. It leave little room for doubt or argument.

Exam Question Bill is writing a new software application for a small real estate company. Four real estate agents from the company all want an application on their mobile phones that allows them to access the data files back at the office while they are out. Each agent has a different model/make of phone. To obtain information to help Bill write the software requirements specification (SRS), the most appropriate action for him to take is to A. interview all four real estate agents. B. observe one real estate agent at work. C. survey at least four clients to find out what they would like. D. interview at least four clients to find out what they would like.

More Examples Other information, however, cannot be so scientifically collected: opinions, for example. For these cases, it would be appropriate to conduct interviews, surveys, questionnaires to gather workers' feelings. – Survey staff on their feelings of stress when dealing with a program. – Ask customers how attractive they think a system's output is – Appeal Rating – Conduct a poll to summarise how easy users think a tool is to use. - User Friendliness Rating. Do not confuse the two methods. – Don't survey people whether they think the existing system is expensive to run – Don't try to measure people's feelings of comfort when using some software.