COSC 319 Chapter #3

What factors drive the design of most software products?

Business and customer needs that are not met by current products, dissatisfaction with existing products, and technology changes that make new types of products possible.

What is a ‘feature’ of a software product?

A fragment of functionality that is offered by a software product.

Explain how personas, scenarios and user stories can contribute to feature design.

Personas inspire scenarios; scenarios are developed into stories and inspire features; stories define features.

What is a persona?

An imagined user where you create a character portrait of a type of user that might use your product.

What information should be included in a persona description?

Information about the person themselves, their job, their educational background and experience, and why they might be interested in using the product.

What is a scenario?

A narrative that describes how a user might use a software system to do something that they want to do.

What are the most important elements that may be included in a scenario description?

Scenario name, overall objective, what's involved in reaching the objective, personas of actors involved, problems that can't be addressed by the existing system and possible ways that problem can be tackled, and a possible requirement to include a very specific feature in a system.

What is the main problem with using a structured approach to scenario description?

Users who have to understand scenarios find structured descriptions intimidating and hard to understand.

What are the problems of writing goal-based scenarios?

It is often easier for users to articulate how to do some task using an existing system rather than providing a more abstract description of their goals.

How can users get involved in the development of scenarios?

Based on a scenario, users can point out what's wrong, suggest how it can be extended, and ask questions about stuff they don't understand.

What is a user story?

A fine-grained narrative that sets out a single thing that a user wants from a software system in a structured way.

Show a typical form of a user story and explain its constituent parts.

As a <role> I <want|need> to <do something> so that <reason>.

Why should you use user stories as well as scenarios when deriving a feature list for a software product?

User stories add detail to a scenario and can serve as a system feature description.

Explain why you should normally avoid writing ‘negative stories’.

It is impossible to write tests that conclusively demonstrate a negative.

What are the most important characteristics of software features?

Independence, coherence, and relevance.

List six important factors in feature set design.

Simplicity, functionality, familiarity, novelty, automation, and control.

What is ‘feature creep’?

The numbers of features in a product "creep up" as new potential uses of the product are thought of.

Explain how you can identify features from a scenario description.

Highlight key phrases in the interactions description that describe specific software functionality that is used.

Explain how features can be described and defined using user stories.

A feature description can have a set of user stories associated with it where each story describes a different aspect of the feature.

Explain why user research on its own is not necessarily sufficient when designing software products.

User research shows how people do things at the moment but does not account for the possibility of product innovations changing the ways that things are done.