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1 SYS366 Week 5 - Lecture 1 Systems Requirements Gathering: Identifying Software Requirements
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2 Agenda Identifying Software Requirements – Functional Requirements – Technical Requirements – Data Requirements Fact Finding Methods
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3 Identifying Requirements Objective of the requirements capture and analysis phases is to understand business processes and develop requirements for the new system
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5 Identifying System Requirements “A requirement is a desired feature, property or behavior of a system.” * * Unified Modeling Language
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7 Identifying System Requirements “Features can be functional or non-functional.” * * Use Case Modeling, by Bittner & Spence, page 75.
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8 Identifying System Requirements Software Requirements – “Individual statements of conditions and capabilities to which the system must conform.” * * Use Case Modeling, by Bittner & Spence, page 6.
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9 Identifying System Requirements Each Software Requirement Is the specification of an externally observable behavior of the system – Inputs to the system – Outputs from the system – The processing of the system – Attributes of the system – Attributes of the system environment Use Case Modeling, by Bittner & Spence, page 5.
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10 What is Software Development? Software Development implies developing some software – but it does not involve simply coding programs Software is developed to turn manual processes into automated processes or to improve/enhance existing automated processes.
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11 What does this have to do with Systems? Software Development entails understanding the problem to be solved, understanding how a business operates and understanding that the solution to be developed will be of value to the business
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12 Identifying System Requirements “Software Requirements specify the things that the software does on behalf of the user or another system.” * * Use Case Modeling, by Bittner & Spence, page 6.
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13 Requirements Gathering Analyst needs to find out what the user requires in the new system or what the user requires to be changed in an existing system – Gather the requirements by doing fact finding – Document the requirements
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14 Requirements Gathering For an existing system, analyst needs to find out: – Functionality Some of the functionality of the existing system will be included in the new system (can be acquired from existing documentation and code) – Data needs Some of the data of the existing system will need to be migrated into the new system
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15 Requirements Gathering For a new system, analyst needs to find out: – Functionality What are the activities the system needs to perform? How is the user to interact with the system? Are other systems to interact with the system? – Data needs What information is needed?
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16 Requirements Gathering Scope of the System Functional TechnicalData Requirements Requirements Requirements
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17 Functional Requirements Describe what a system does or is expected to do “Specify the input and output behavior of a system”* *Use Case Modeling, by Bittner & Spence, page 8.
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18 Functional Requirements Include – Descriptions of the processing which the system will be required to carry out – Details of the inputs into the system from paper forms and documents or the interactions between people and the system or transfers from other systems – Details of the outputs that are expected from the system in the form of printed documents and reports, screen displays and transfers to other systems :
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19 Technical Requirements “Specify the other qualities that the system must have, such as those related to the usability, reliability, performance and supportability of the system”* Describe the aspects of the system that are concerned with how well it provides the functional requirements. Include: – Performance criteria – Anticipated volumes of data – Security requirements *Use Case Modeling, by Bittner & Spence, page 8.
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20 Data Requirements Describe what information the system is going to need or produce – really a part of Functional and Technical Requirements Include – Details of the data that must be held in the system
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21 Themes To Guide Investigation What are business processes and operations? How should the business processes be performed? What are the information requirements? Understand the Users’ Needs!
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22 Today Identifying System Requirements – Functional Requirements – Technical Requirements – Data Requirements Fact Finding Methods
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23 Fact Finding Methods Conduct interviews and discussion with users Distribute and collect stakeholder questionnaires Review existing reports, forms, and procedure descriptions Observe business processes and workflows Build prototypes Conduct JAD sessions
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24 Fact Finding Methods – Interviews – Questionnaires – Review Documentation – Observation – Prototypes – JAD sessions – RAD
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25 Interviews We are going to concentrate on interview techniques; the rest of the slides explain the other methods for fact finding
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26 Interviews Primary technique for fact finding and information gathering Most effective way to understand business functions and business rules Usually requires multiple sessions Usually conducted with customers/clients/users Clients are not always able to express their requirements clearly it is up to the analyst to ask the right questions to help the client express their requirements
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27 Conducting effective interviews – Determine who you are going to interview – Know what information that stakeholder can provide for you – Prepare for the interview – Conduct the interview – Follow up on the interview
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28 Determine who you are going to interview Can be business or technical stakeholders – Business stakeholders provide the functional and data requirements – Technical stakeholders provide the technical and data requirements
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29 Determine who you are going to interview Executives – Will provide information related to strategic issues about the business – Need statistical and summary information Management – Will provide a broad perspective about the business as well as information about the system being developed – Need statistical and summary information
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30 Determine who you are going to interview Operational staff – will provide information about how the work is actually done – Domain experts
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31 Types of interviews Structured Interview – Formal style – Requires significant preparation Unstructured Interview – Informal – No pre-determined questions or objectives
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32 Structured Interview Preparing for the interview – Establish the objectives for the interview – Have a clear agenda – Prepared in advance with a list of open and closed ended questions – Set the time and location for the interview – Inform all participants of the objective, time and location
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33 Structured Interview Questions – Questions should allow you to keep on track and avoid getting off topic during the interview – Keep length of questions reasonable (15-20 words or less)
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34 Structured Interview Questions can be prepared from any of the following: – Observations made when existing form and reports may have been reviewed – Observations made when reviewing the strategic, tactical or operational plans – Observations made when observing employees doing current job tasks
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35 Structured Interview Phrase questions to avoid misunderstandings - use simple terms and wording Do not ask questions that give clues to expected answers Avoid asking two questions in one Do not ask questions that can raise concerns about job security or other negative issues
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36 Structured Interview Questioning Strategies How can order processing be improved? How can we reduce the number of times that customers return items they’ve ordered? How can we eliminate shipping the wrong products? High-level: very general Medium-level: moderately specific Low-level: very specific Top Down Bottom UP
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37 Structured Interview Open ended questions – Encourages unstructured responses and generates discussion – Useful when you need to understand a larger process or to draw out opinions or suggestions from the person being interviewed – Examples What do you think about the current system? How do you decide what type of marketing campaigns to run?
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38 Structured Interview Closed ended questions – Limited or restricted response – a simple definitive answer – Used to get information that is more specific or when you need to verify facts – Examples: How do customers place orders? How many orders to you receive a day?
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39 Structured Interview How to conduct the interview – Dress appropriately; Arrive on time – Welcome the participants; introduce the attendees; state the objective and agenda – Ask permission if you want to tape record the interview – Ask questions from script
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40 Structured Interview How to conduct the interview – Listen closely to the interviewee and encourage them to expand on key points – Take thorough notes – Identify and document unanswered questions – At end of interview, review outstanding questions that require follow up – Set date and time for the next, follow-up interview
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41 Fact Finding Methods – Interviews – Questionnaires – Review Documentation – Observation – Prototypes – JAD sessions – RAD
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42 Questionnaires A document which contains a number of questions Can be paper form or electronic form (email or web- based) Allows the analyst to collect information from a large number of people – People outside the organization (I.e. customers) – Business users spread across a large geographic area
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43 Questionnaires Limited and specific information from a large number of stakeholders Preliminary insight Not well suited for gathering detailed information Open-ended questions vs. close-ended questions
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44 Questionnaires Similar process to interviewing – Determine who will receive the questionnaire – Design the questionnaire Determine objective of questionnaire Design questions – Follow up questionnaire
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45 Questionnaires Determine who will receive the questionnaire – Select a sample audience who are representative of an entire group – Assume 30-50% return rate for paper and email questionnaires – Assume a 5-30% return rate for web-based questionnaires
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46 Questionnaires Design the Questionnaire – Clearly state the following in the questionnaire: The purpose of the questionnaire Why the respondent was selected to receive the questionnaire When the questionnaire is to be returned
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47 Questionnaires Design the Questionnaire – Let the respondent know when/where they can see the accumulated questionnaire responses – Consider providing an inducement to have the respondent complete the questionnaire (I.e. a pen)
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48 Questionnaires Design the Questionnaire – Keep the questionnaire brief and user friendly – Provide clear instructions on how to complete the questionnaire – Arrange the questions in a logical order; going from easy to more complex topics
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49 Questionnaires Design the Questionnaire – Phrase questions to avoid misunderstandings, use simple terms and wording – Do not ask questions that give clues to expected answers – Avoid asking two questions in one – Limit the use of open ended questions that will be difficult to tabulate
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50 Questionnaires Design the Questionnaire – Do not ask questions that can raise concerns about job security or other negative issues – Include a section at the end of the questionnaire for general comments – Test the questionnaire whenever possible on a small test group before finalizing it
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51 Fact Finding Methods – Interviews – Questionnaires – Review Documentation – Observation – Prototypes – JAD sessions – RAD
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52 Review Existing Reports, Forms, and Procedure Descriptions Purposes – Preliminary understanding of processes – Guidelines / visual cues to guide interviews Identify business rules, discrepancies, and redundancies Be cautious of outdated material
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53 Reviewing existing documentation Most beneficial to new employees or consultants hired to work on a project Types of documentation that is reviewed: – Company reports – Organization charts – Policy and Procedures manuals – Job Descriptions – Documentation of existing systems
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54 Reviewing existing documentation Allows the analyst to get an understanding of the organization prior to meeting with employees Allows the analyst to prepare questions for either interviews or questionnaires (other fact finding techniques)
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55 Fact Finding Methods – Interviews – Questionnaires – Review Documentation – Observation – Prototypes – JAD sessions – RAD
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56 Observation An effective way to gather requirements if obtaining complete information was not effective through other fact finding techniques (I.e. interviews and questionnaires) Or An effective way to verify information gathered from other fact finding sources (such as interviews)
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57 Observation Observation can be done by having the analyst observe the client from a distance (without actually interrupting the client) or by actually doing the work of the client
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58 Observation Should be carried out for a period of time and at different time intervals, not just once, so that the analyst can observe different workloads and to ensure that what the client does is consistent over different periods of time
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59 Observation Allows the analyst to follow an entire process from start to finish Can upset the client if they feel threatened by new activity going on around them – the client may behave differently from what they normally do
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60 Fact Finding Methods – Interviews – Questionnaires – Review Documentation – Observation – Prototypes – JAD sessions – RAD
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61 Prototypes A demonstration system – Represents a graphical user interface – Simulates system behavior for various events – Any data displayed on a GUI screen is hard-coded; not retrieved from a database Constructed to visualize the system Allows the customer to provide feedback An effective way to gather requirements for a new system Supports JAD or RAD type sessions
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62 Fact Finding Methods – Interviews – Questionnaires – Review Documentation – Observation – Prototypes – JAD sessions – RAD
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63 Other Methods Joint Application Development (JAD) – A series of workshops that bring together all stakeholders (users and systems personnel)
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64 Other Methods Joint Application Development (JAD) – Consists of the following types of attendees: Facilitator: the person who conducts the meeting and keeps it on track (generally the analyst) Note taker: the person who records the information for the session Clients/Customers/Users: the people who communicate the requirements, take decisions and approve the project Developers: the people who are part of the development team and need to gather information
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65 Other Methods Joint Application Development (JAD) – Takes advantage of the group dynamics – Increased productivity – May require more than one session – One session may last a few hours, several days or several weeks
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66 Fact Finding Methods – Interviews – Questionnaires – Review Documentation – Observation – Prototypes – JAD sessions – RAD
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67 Other Methods Rapid Application Development (RAD) – An approach to software development where the system solution is delivered – fast – Most appropriate for systems which are not the organization’s core business
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68 Other Methods Rapid Application Development (RAD) – Can result in: Inconsistent GUI designs Poorly documented systems Software that is difficult to maintain
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