Analysis of Usability Requirements and Priorities
Answered
This assignment is designed to provide practical experience of analysing usability requirements, and carrying out an analysis of usability requirements and priorities, performing a systematic usability evaluation using a standard method, and producing a report of your findings.
Your firm of interaction design consultants is trying to build up a portfolio of impressive work, to enable it to pitch for business convincingly in the future.
Your task is to produce a set of usability requirements and a usability evaluation of an interactive system, plus a report of your results, by applying a systematic evaluation methodology. You have a completely free choice of what interactive system you evaluate.
Producing the usability evaluation assignment will involve
- Choosing an interactive system to study.
- Identifying the use cases or aspects of the functioning of the system to be considered, and briefly describing them in your documentation. (These don’t need to be a complete set of use cases; for very complicated systems focusing on one part of what they do is just fine. However you should give a clear indication of what subset of the functionality of the system you are considering, and what you are not considering. If in doubt, cover less functionality in more detail.)
- Define a set of usability requirements, considering what the design really needs to get right to achieve a good user experience, and defining the requirements precisely enough that it would be possible to measure the system’s performance.
- Choosing an evaluation methodology. You should apply a standard evaluation methodology such as user testing, cognitive walkthrough, or heuristic evaluation.
- Defining an evaluation procedure. This will include stating one or several user tasks to be tested or considered with exact descriptions of the scenario and the goal the user is trying to achieve, as well as what the evaluator will do to collect results and produce an evaluation. The evaluation procedure needs to be described in full, separately from the description of the results.
- Carrying out the evaluation. This will involve applying the procedure and documenting what happens, and what the procedure finds. (If applying your procedure looks like an excessive amount of work, or producing an excessively large volume of documentation, ask advice; we would prefer an evaluation giving detailed insight into part of the functionality to an evaluation with broad coverage but a thinner or more superficial analysis.)
- Deriving findingsabout the usability of the interactive system from the results of the usability evaluation. This should include consideration of how strong and how general the conclusions are.
Your report should comprise the following elements:
- Part One: The interactive system and its users. A brief statement of what the interactive system is and what it does – sufficient to make the rest of the report comprehensible; plus a description of the user populations and the assumptions it is reasonable to make about the capabilities of the users. The word count should be between 150and 400 words – longer only if really needed.
- Part Two: The use cases. Brief accounts of the use cases considered, plus a statement of what you are notconsidering, if you are only looking at part of the system. A use case diagram is optional. The word count should be between 100 and 300 words.
- Part Three: The usability requirements. Brief but exact statements of fiveprecisely focused, testable usability requirements. The word count should be between 300 and 600 words.
- Part Four: The evaluation methodology. An exact description of the evaluation procedure to be followed, including what the methodology you are using, exact descriptions of user tasks being considered, instructions to be given to users in user testing, or the set of guidelines used in heuristic evaluation. In principle, you need step by step descriptions of the correct procedures for completing the use cases you are considering in a heuristic evaluation or cognitive walkthrough, or asking people to perform in a user trial. However if the tasks are long and complicated with a variety of possible paths, something briefer might be needed; consider what is cost-effective, and ask advice if in doubt. The word count should be between 300and 800 words, plus documentation of instructions or task steps if included.
- Part Five: The evaluation. The results of applying the evaluation procedure: what you saw test subjects doing, measurements of their performance, answers to questions and so on; or evidence for violation of particular design guidelines; or descriptions of how and why beginning users might go wrong in particular places, etc. The word count should be between 1000and 2500 words.
- Part Six: The findings of the evaluation. The findings of your evaluation about the usability of the interactive system. Include comments on how the findings relate to the results of the evaluation procedure, and ideally about how strong the evidence is, as well as judgements of how serious you think the usability problems are. An itemized bullet point structure is likely to be easier to read than long paragraphs of text. This should also include an appraisal of the strengths and weaknesses and successes and failures of the evaluation process. The word count should be between 500and 1000 words.