System Analysis-Gathering Requirements

 System analysis is the process of gathering info about existing system, which may be computerized or not, while identifying system’s strengths and problems.  Commonly used info gathering techniques are: Interviews Review of document Observation Questionnaires Joint Application Design Prototyping

 Interviews Reveals info about the interviewee opinions about existing system. 4 basic steps in an interview are :-  Read the background materials to establish the interview objectives  Decide who to interview  Prepare the interview  Decide on question type and structure It is a formal face to face meeting between system development team and user

There are two types of interview:  Structured  The interviewer will only ask questions that have been planned and write in advance  Unstructured  The interviewer will ask questions that have been prepared earlier and also other subjects if they seem appropriate Advantages :  Get to meet the person personally and get more info if asked correctly  Reveals what actually being done  Indications of resistance to the proposed system

Disadvantages:  Time consuming to undertake  More costly

 Review of documents Written doc includes manuals, procedures, forms reports etc Copies of documentation should be able for review Reviewing such documentation can reveal about the organization, operation and its existing system It is important to:  Identify a complete list of doc

 Go through them  Analyze  Check for duplication of data to ensure it is not appear under two names By reviewing doc, more effective interviews can be conduct with managers and users.  Observation Allows to gain info that cannot get by other techniques

First hand info can be obtained Direct observation is where system analyst watches the users as they performing their job function It enables us to see the reality situation rather than listening to others Used as supplementary interview info or acts as a signal any extra care to be taken into account

 Questionnaires Are used when there are large number of users The questions should be reasonably straightforward and relatively few to increase the likelihood of response Cheaper and quicker way to interview but difficult to set a clear questions and ensure adequate response rate

Advantages :  Obtain info from large number of people with less time and money Disadvantages :  Info maybe less detailed  Info could be bias if only a few respond to the survey  Joint Application Design Info gathering technique that allows a system dev team, users and mgt to work together in a focused workshop to identify requirements for the system Effective in building user commitment through their participation in analysis of requirements and specifications of systems design Advantages :  It takes shorter time to complete a project  Improves the quality of final system by focusing on up-front SDLC,thus reducing errors

 Prototyping is a model of a proposed system Acts as a communications device between users and system dev team and aid in the learning process Has five main stages :  Agree approximately what is needed  Build something quickly that look like what is wanted  Test it and see if it does what the user wants

 Use it in a representative environment  Adapt and develop the prototype based on the info gained Advantages:  Improve info gathering technique process  Improve relationship between system dev team and user  Better identification of systems problems Disadvantages :  Potential cause of conflict between dept that want different things from the system

 Misunderstanding by end user that actual system can be design and dev at same speed