540-310-0310-2004.ppt

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540-310 Human Factors in Information Seeking and Use

Wooseob Jeong

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Usability Test Assignment (1)

Part I: Select Target Product Decide your target device. Anything can be

your subject: paper manuals, electronic devices, tools, web sites, software, hardware, but the list should not be limited.

Pick one device, and describe what's the thing for: what's the expected function, utility, and advantage? who use it?

200 words – No more than 1 page! Plus, “informed consent form” Due on 3/17 (5%)

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Usability Test Assignment (2)

Part II: Usability Test & Report Identify any usability problems by testing at

least three subjects, who should be available easily like your room mates or family members.

Before testing, you should carefully develop appropriate tasks. The problems should be addressed in terms of usability perspective, especially time, effort, and error.

Based on your findings, you should suggest any modification for the improvement of usability.

500-1000 words – tables & figures - 15%  Due on 4/7

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Logical User-Centered Interactive Design Methodology

1. Develop product concept2. Performance research and needs

analysis3. Design concepts and key-screen

prototype4. Do iterative design and refinement5. Implement software6. Provide rollout support

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Three principles of a user-centered design

1. An early focus on users and tasks.

2. Empirical measurement of product usage.

3. Iterative design whereby a product is designed, modified, and tested repeatedly.

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User-centered design techniques

Participatory designFocus group researchSurveysDesign (structured) walk-throughPaper-and-pencil evaluationsExpert evaluationsUsability auditUsability testingField studiesFollow-up studies

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Participatory Design

One or more representative users on the design team itself.Typically used for the development of in-house systems.The representative users can become too close to the design team.

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Focus Group Research

The very early stages of a project in order to evaluate preliminary concepts using representative users. Simultaneous involvement of more than one participant. To explore a few people’s judgments and feelings in great depth, and in so doing learn how end users think and feel.Structured monitoring

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Surveys

To understand the preferences of a broad base of users about an existing or potential product.It can use larger samples to generalize to an entire population. Any time in the life cycle, but early stages are better.Languages must be crystal clear and understood in the same way by all readers.

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Design (structured) walk-throughs

First developed by IBMTo explore how a user might fare with a product by envisioning the user’s route through an early concept or prototype of the product. Guide & monitoring

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Paper-and-pencil Evaluation

Users are shown an aspect of a product on paper and asked questions about it. Critical information can be collected quickly and inexpensively. Ex) Menu system, table of contents in HELP. Repeated conducts without big expense

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Expert Evaluation

A review of a product or system, usually by a usability specialist who has no involvement in the project. “Double” specialist (usability and the area) is more effective than a usability expert.

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Usability Audit/Testing

Usability Audit Comparing the design of a product

against checklists of standards.

Usability Testing Employs an iterative cycle of tests

intended to expose usability deficiencies and gradually shape or mold the product in question.

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Field Study

Review of a product that has been placed in its natural setting, such as an office or home, just prior to release. Advantage: the exposure of the product to actual working conditionsDisadvantage: the loss of control over the data collection – minimize the effectiveness by “let us know what you think”

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Follow-up Studies

Conducted after formal release of a productCollect data for the next release, using surveys, interviews, and observations. Unfortunately, rare!

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Goals of Usability Testing (1)

Of course, to ensure the creation of products that: Are easy to learn and to use Are satisfying to use Provide utility and functionality that

are highly valued by the target population

Specifically, …

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Goals of Usability Testing (2)

Creating a historical record of usability benchmarks for future releases.Minimizing the cost of service and hotline calls. Increasing sales and the probability of repeat sales.Acquiring a competitive edge since usability has become a market separator for products.Minimizing risk.

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Five Usability Attributes (1)

Learnability The system should be easy to learn so that the

user can rapidly start getting some work done with the system.

Efficiency The system should be efficient to use, so that

once the user has learned the system, a high level of productivity is possible.

Memorability The system should be easy to remember, so that

the casual user is able to return to the system after some period of not having used it, without having to learn everything all over again.

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Five Usability Attributes (2)

Errors The system should have a low error rate, so

that users make few errors during the use of the system, and so that if they do make errors they can easily recover from them. Further, catastrophic errors must not occur.

Satisfaction The system should be pleasant to use, so

that users are subjectively satisfied when using it; they like it.

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Limitations of Usability Testing

Testing is always an artificial situation.Test results do not prove that a product works.Participants are rarely full representative of the target population.Testing is not always the best technique to use.

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Usability Lab Tours

http://www.sois.uwm.edu/Jeong/540310/usability_tour.htmIn-class demo!Career Development

Rubin, Jeffrey (1994) Handbook of Usability Testing, Wiley. 0-471-59403-2

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Four Types of Usability Tests

Exploratory Test Preliminary stage; skeleton

Assessment Test Middle stage; most typical; body

Validation Test Late stage; verification, just before release

Comparison Test Different interfaces in the same product;

with competitors’ products

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Informed Consent Form

Participants should always be treated with respect and should be informed that it is not they who are being tested; rather, it is the software and user interface that are under study. They should be told about what they will be doing and how long they will be expected to stay. Participation should always be voluntary, and informed consent should be obtained.

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Example of Informed Consent Form

http://www.sois.uwm.edu/jeong/540310/consent.htm“I have freely volunteered to participate in this experiment.”“I have been informed in advance what my task(s) will be and what procedures will be followed.”“I have been given the opportunity to ask questions and have had my questions answered to my satisfaction.”IRB approval waived in classroom.

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Typical Test Routine

Introduction Make participants comfortable

Pre-questionnaire Background info like age, sex, experience

Main Test Talk Aloud

Post-questionnaire Confirmation of test results

Debriefing Wrap-up conversation

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Task Component and Description

Task Load paper into the copier.

Machine State Copier with four labels attached and an

empty cassette tray.Successful Completion Criteria Test subject loads paper into cassette after

first fanning the stack of paper.Benchmark Load correctly within one minute.