Chapter 12/13: Evaluation/Decide Framework Question 1

It’s part of a design process! Every organization that builds things has some design process. Good idea to have it be a conscious one, that you can follow consistently… And change consciously if it’s not working!

For ID - Why Evaluate? Why: to check that users can use the product and that they like it. Designers need to check that they understand users’ requirements. Avoid wasting money Question 2

What to Evaluate What: a conceptual model, early prototypes of a new system and later, more complete prototypes.

Where to Evaluate Where: in natural and laboratory settings.

When to Evaluate When: throughout design; finished products can be evaluated to collect information to inform new products.

The language of evaluation Analytical evaluation Controlled experiment Formative evaluation Heuristic evaluation Predictive evaluation Summative evaluation Usability laboratory User testing Start Question 3

Evaluation approaches Usability testing Field studies Analytical evaluation Combining approaches Start Question 4!

Characteristics of approaches Usability testing Field studies Analytical Usersdo tasknaturalnot involved Locationcontrollednaturalanywhere Whenprototypeearlyprototype Dataquantitativequalitativeproblems Feed backmeasures & errors descriptionsproblems …More for Question 3

Evaluation approaches and methods MethodUsability testing Field studies Analytical Observing x x Asking users x x Asking experts x x Testing x Modeling x End Questions 3, 4

Six evaluation case studies Evaluating early design ideas for a mobile device for rural nurses in India. Evaluating cell phones for different markets. Evaluating affective issues: challenge and engagement in a collaborative immersive game. Improving a design: the Hutch World patient support system. Multiple methods help ensure good usability: the Olympic messaging system (OMS). Evaluating a new kind of interaction: an ambient system.

Team Extra Credit Book Exercise in Chapter 12 (Interaction Design Book – See p 450 in the 3 rd Ed). Due with Milestone 4.

DECIDE: a framework to guide evaluation Determine the goals. Explore the questions. Choose the evaluation approach and methods. Identify the practical issues. Decide how to deal with the ethical issues. Evaluate, analyze, interpret and present the data.

Determine the goals What are the high-level goals of the evaluation? Who wants it and why? Some examples of goals: Check to ensure that the final interface is consistent. Investigate how technology affects working practices. Improve the usability of an existing product.

Explore the questions All evaluations need goals & questions to guide them. What questions might you ask about the design of a cell phone?

Choose the evaluation approach & methods The evaluation approach influences the methods used, and in turn, how data is collected, analyzed and presented. E.g. field studies typically: Involve observation and interviews. Do not involve controlled tests in a laboratory. Produce qualitative data.

Identify practical issues For example, how to: Select users Stay on budget Stay on schedule Find evaluators Select equipment Question 5

Decide about ethical issues Develop an informed consent form (see example on pp of the ID book!)  Do one for class on Friday! Participants have a right to: - Know the goals of the study; - Know what will happen to the findings; - Privacy of personal information; - Leave when they wish; - Be treated politely. Question 6

Evaluate, interpret & present data The approach and methods used influence how data is evaluated, interpreted and presented. The following need to be considered: - Reliability: can the study be replicated? - Validity: is it measuring what you expected? - Biases: is the process creating biases? - Scope: can the findings be generalized? - Ecological validity: is the environment influencing the findings? - i.e. Hawthorne effect. Question 7