10 - Evaluating Interactive Systems

Question 1

What is the difference of analytic and empirical design evaluation?

Answer 1

Analytic: identifies characteristics of the design zB form, color, material, distribution
Empirical: helps to understand the context for object properties zB why a axe have a specially shaped handle?

Question 2

what is the difference between formative and summative evaluation?

Answer 2

The formative evaluation focuses on understanting the user requirements and mental models. The central question is “How to design it” and it is more qulitative. More at the and of the design process, the summative evaluation focuses on understand how good a design ist, based on criteria, ratings and measures and it is more quantitative.

Question 3

What is the main idea of heutistic evaluation? Is this method formative or summative, analytic or empirical?

Answer 3

The main idea it that a few evaluators examine the UI and judge its compliance with usability principles like for example: “Does every display begin with a title or header that describes screen contents?”, weighted by severity.

Question 4

what is tipically the number of evaluators and why?

Answer 4

4-5 due the convergence behavior of the function of problem found against number of evaluators

Question 5

call advantges and disadvantages of heuristic evaluations

Answer 5

advantages: Quick, cheap, easy evaluation of early UI design
disadvantages: Relies on creativity and experience of the evaluators.

Question 6

explain the ideia behind Cognitive Walkthroughs

Answer 6

Experts go through tasks, specified by the designers, step by step with a set of questions. If problems are expected, they should be described.