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SOFTWARE REQUIREMENTS ENGINEERING

LECTURE # 4 ,

TEAM SKILL 2 : UNDERSTANDING USER AND

STAKEHOLDER NEEDS

REQUIREMENTS ELICITATION TECHNIQUES l –

& ll

Apr, 2022 Engr.^ Dr. M Sohail

Software Requirement Engineering

What is software requirement Functional vs Non Functional Requirement Source of Requirement Goal of Software Development Root Causes of Project Success and Failures The High Cost of Requirement Errors The Problem Domain The solution domain Problem Domain defines the environment where the solution will come to work, the solution domain defines the abstract environment where the solution is developed

7 processes in SRE

Inception Task • Inception means specifying the beginning of the software project. Most of the s/w projects get started due to the business requirement.

**- During inception, the requirements engineer asks a set of questions to establish…

1. A basic understanding of the project
2. Find out all possible solutions and to identify the nature of the** **solution
3. Establish effective communication between the customer and the** developer Elicitation Task • Before the req. can be analyzed and modeled they must undergo through the process of elicitation. **Eliciting requirements is difficult because of

• Scope of the Project • Understanding the Problems. • Problems of volatility
• Elicitation may be accomplished through two activities • Collaborative requirements gathering • Quality function deployment**

❑ The Challenge of Requirement Elicitation ❑ Requirement Elicitation ❑ The Requirement Elicitation Process ❑ Requirement Elicitation Techniques- l ✓ Interviews ✓ Questionnaires ✓ Background Reading ✓ Introspection ✓ Social Analysis

TEAM SKILL 2: UNDERSTANDING USER AND STAKEHOLDER NEEDS

REQUIREMENTS ELICITATION TECHNIQUES l – & ll

Requirements Elicitation

In requirements engineering, requirements elicitation is the practice of researching and discovering the requirements of a system from users, customers, and other stakeholders.

Requirements Elicitation Process

5

❑ Background Knowledge

❑ RequirementsGathering

❑ RequirementsClassification

❑ RequirementsConflict

❑ RequirementsPrioritization

✓ Interviews ✓ Questionnaires ✓ Background Reading ✓ Introspection ✓ Social Analysis ✓ Requirements Workshops ✓ Brainstorming and Idea Reduction ✓ Story Boarding ✓ Role Playing ✓ Prototyping ✓ Requirements Reuse

8 Requirements Elicitation Techniques

Social Analysis

❑ Social Analysis is a process of collecting requirements

❑ By observing the people doing their normal work.

❑ Find the additional requirements needed by the user, when the user is unable to

explain

❑ This Social Analysis can be of the following types::

✓ Passive Observation ✓ Active Observation ✓ Explanatory Observation 25

Social Analysis

Explanatory Observation

❑ In this type of observation the user talks loudly, explaining what they are doing while using the product. ❑ Theobserver takes notes using the explanation given by the user 28

Interviews [1]

❑ A simple, direct technique that can be used in nearly every situation.

❑ In this method the requirement engineering analyst’s discuss with different types of

the stakeholders to understand the requirements of the system

❑ There are two main typesof interviews:

✓ Closed Interviews

✓ Open Interviews

9

Questionnaires [1]

15 ❑ Questionnaires are one easy methods of gathering requirements from a large number of people only in lesser time. ❑ Can be manual (paper form) or electronic (soft form distributed through e-mail) ❑ The resultsextracted fromthe Questionnairesmust be clearly analyzed ❑ A well designed and effective questionnaire can be usedto decide the actual user requirements, objectives and the constraints

The steps involved in designing and conducting the Questionnaires are:: ❑ The purpose of survey should be clearly defined ❑ The Sampling group (respondents of the survey) should be decided ❑ Clearly state Why the respondent was selected for questionnaire ❑ Provide clear instructions on how to complete the questionnaire ❑ Avoid asking two questions in one ❑ Do not ask questions that give cluesto answers ❑ Keep the questionnaire brief and user friendly ❑ Preparing and developing the questionnaire ❑ Conducting the questionnaire process ❑ Gathering and analyzing the results 16

The Designing of Questionnaires

Introspection

22 ❑Introspection is a process by which a reliance on one’s own observation, inner thoughts, and desires are emphasized. ❑The authors criticize introspection because it mainly highlights the thoughts and imagination of the expert who is developing software instead of focusing on user needs. ❑Combining both expert imagination and user requirements contributes to a stronger platform

▪ Introspection is an easier

technique to apply

Introspection can be very inaccurate at times because Requirement Analyst imagines what is required rather than asking from the user what he requires This technique is unlikely to reflect the stakeholder’s goals and actual user experiences 24

Introspection