Requirements Elicitation Techniques Part 7 – Interviews

Planning

Interviewing is a systematic approach to eliciting requirements. You can interview an individual or a group of people, in a formal or informal setting. You ask questions relevant to the project and document the responses.

Interviewing should not be the only technique you use to elicit requirements. You will not know all the questions you need to ask. That is why I am a big fan of the Event/Response method (I have a prior series of posts on this method). The flow of that methodology creates the questions you will need to ask to ferret out all of the requirements.

In a structured interview, you have a predefined  set of questions. These will be based on how much you already know about the area under study. Here are some sample interview questions:

  • What are the business objectives for this project?
  • What are your biggest challenges?
  • What worries you about this project?
  • Who is impacted (good or bad) by this project?
  • How are they impacted?
  • Are their known changes or projects that impact this one?
  • What business processes are impacted?

When interviewing, avoid “yes or no” questions and pay careful attention to the answers. It helps to have someone document the answers for you so you can focus on paying attention to the answers. They usually will lead to follow up questions that are not on your script. Be prepared to deviate from the script if necessary.

In an unstructured interview, topics are discussed in an open-ended way. You don’t have a script, so the answers are used to spring-board into subsequent questions.

If possible, you should establish in advance a trust and rapport with the interviewee. This will make them more comfortable to be open and honest with you.

 

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Requirements Elicitation Techniques Part 6 – Document Analysis

Planning

Document Analysis is simply gathering and reviewing all existing documentation related to the scope of the project. It can be very useful in identifying the “as is” state as well as help to uncover Business Events for your Event/Response analysis.

There are three stages to document analysis

  • Stage 1 – Identify the relevant materials
  • Stage 2 – Study the materials, take notes and list follow up questions
  • Stage 3 – Get answers, organize the information into your requirements format

One of the major cons of document analysis is that documentation is often not kept up to date. You will have to verify the validity of anything you plan to use.

Here is a list of documents which can be useful:

  • Business Process Documentation
  • Training / User Guides
  • Functional specs of existing system
  • Business Rules
  • Organization Charts
  • Emails
  • Contracts
  • Help Desk Incident Reports
  • Project Documentation for prior projects in the area under study
  • Existing user enhancement requests

 

Requirements Elicitation Techniques Part 5 – Data Modeling

Planning

Data modeling is a complex topic. Becoming a professional data modeler takes months or years of education plus practical experience. It is not my intent to teach data modeling in this brief post, but to show how it related to requirements elicitation.

I introduced some of the concepts of data modeling in Part 4 of this series, “Business Rules Analysis”. The relationships between entities are the business rules and they are fixed in the structure of the data. Examples of these rules are “A Customer lives at one or more Addresses” and “An Address may contain one or more Customers”.

Entities can be found in the nouns in your requirements. They are people, places and things about which the organization wishes to store data. In the example above, “Customer” and “Address” are entities and are therefore capitalized in the rules statements.

Attributes are the elemental pieces of data that are associated with each Entity. In the logical data model, each attribute must be stored with one and only one Entity. The logical data model represents the business Entities, Attributes and Relationships without regard to physical implementation.

The physical data model represents how the logical data model will be implemented in a relational database. Here are two examples of the differences between the logical and physical data models:

  • In the logical model, you can have “many to many” relationships as in the Customer / Address example above. In the physical model you cannot implement many-to-many relationships, so there would need to be an additional table to store each Customer / Address combination.
  • In the logical model,  Attributes belong to one and only one entity. In the physical model, attributes can be included in multiple entities due to inclusion on table keys or for performance reasons.

The data is an important part of requirements gathering. It is an important tool in Event Discovery, as you will ask data related questions such as “What does having this data allow you to do?” and “If I took this data away, what would it prevent you from doing?” Other Event Discovery questions are “What events cause this attribute to be added (or changed, or deleted)?”

I would recommend all Project Managers at least be able to read and understand an Entity-Relationship diagram.

Requirements Elicitation Techniques Part 4 – Business Rules Analysis

Planning

According to the IIBA, a business rule is a specific, actionable, testable directive that is under the control of an organization and supports a business policy. Business rules should be documented independently of how they will be enforced.

“Operative Rules” are intended to guide the actions of people. They are typically found in an organization’s Standard Operating Procedures Manual. For example “an order cannot be placed if the billing address provided by the customer does not match the address on file with the credit card provider”. It is always possible that associates will not always follow an Operative Rule. When you are doing a current system analysis, you may very well find documented rules that are handled differently in each location. By finding out the root cause of why a rule isn’t being followed, it could present a good opportunity to change the rule.

“Structural Rules” structure the knowledge of the organization and cannot be violated. For example “an order must have one and only one payment method”. This type of rule is usually enforced systemically. They can be uncovered during data analysis by constructing an Entity-Relationship diagram. The relationships between entities are the Business Structural Rules.

Other examples of Structural Rules:

  • A Product can be purchased by zero, one or many Customers.
  • A Sales Transaction contains one or more Products
  • A Discount can be applied to zero, one or more Products.
  • A Customer may Purchase zero, one or more Products.

The “zero” relationship is of special interest. It is useful for uncovering additional requirements. For example, in the example above “A Customer may purchase zero, one or more Products” you may ask “How can a Customer purchase zero products?”

The answer may be “A Customer might only apply for a Store Credit Card” or “A Customer may only wish to be added to an email list”. These answers would generate follow up questions regarding the scope of the project.