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Page 1: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

Usability

Page 2: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

User-Based Practices

• Questions

• Organization

• Sign Posting

• Background

Anderson, Chapter 4

Page 4: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4
Page 5: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4
Page 6: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

Usability is…

• Useful: Your content should be original and fulfill a need

• Usable: Site must be easy to use

• Desirable: Image, identity, brand, and other design elements are used to evoke emotion and appreciation

• Findable: Content needs to be navigable and locatable onsite and offsite

• Accessible: Content needs to be accessible to people with disabilities

• Credible: Users must trust and believe what you tell them

Page 9: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

When to Work on Usability

Usability plays a role in each stage of the design process. The resulting need for multiple studies is one reason I recommend making individual studies fast and cheap. Here are the main steps:

• Before starting the new design, test the old design to identify the good parts that you should keep or emphasize, and the bad parts that give users trouble.

• Unless you're working on an intranet, test your competitors' designs to get cheap data on a range of alternative interfaces that have similar features to your own. (If you work on an intranet, read the intranet design annual to learn from other designs.)

• Conduct a field study to see how users behave in their natural habitat.

• Make paper prototypes of one or more new design ideas and test them. The less time you invest in these design ideas the better, because you'll need to change them all based on the test results.

• Refine the design ideas that test best through multiple iterations, gradually moving from low-fidelity prototyping to high-fidelity representations that run on the computer. Test each iteration.

• Inspect the design relative to established usability guidelines whether from your own earlier studies or published research.

• Once you decide on and implement the final design, test it again. Subtle usability problems always creep in during implementation.

Page 10: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

“Usability refers to the quality of a user’s experience when interacting with products or systems, including websites, software, devices, or applications”

• Intuitive design: a nearly effortless understanding of the architecture and navigation of the site

• Ease of learning: how fast a user who has never seen the user interface before can accomplish basic tasks

• Efficiency of use: How fast an experienced user can accomplish tasks

• Memorability: after visiting the site, if a user can remember enough to use it effectively in future visits

• Error frequency and severity: how often users make errors while using the system, how serious the errors are, and how users recover from the errors

• Subjective satisfaction: If the user likes using the system

Page 13: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

Usability Testing

• Planning• Conducting• Interpreting

Page 14: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

• Define your goals

• Choose Testers

• Use the draft/deliverable as your target readers would

• Tasks, Location, Resources, Information Gathering

• Post Task Interview

Page 15: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

Test for Persuasiveness

• Likert-scale questions

• Avoid Bias

• Treatment of Test ReadersTest’s purposeThink they will do during the testTime requiredWhere the test will occurRisksRight to DeclineRight to stop at anytime

Page 16: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

Determine which type of usability test to implement

Depending on where you are in the design process, there are three types of usability tests to choose from. These are the exploratory, assessment, and validation tests. A fourth type, the comparison test, can be used at any point in the design life cycle.

Exploratory Test: The objective is to explore the user's mental model of the task you're trying to facilitate.

• When to use: This type of test is usually conducted during the initial phases of a design life-cycle. This test is effective when the designers are still grappling with what functionality to include in the final product.

• Objective: Evaluates whether the user can distinguish between the functional elements of an interface; whether the user values the functions presented; whether the overall structure enables a "walk up and use" product. The test seeks to establish the intuitiveness of the implementation.

• Methodology: This test involves a high degree of interaction between the monitor and the subject. The purpose of the test is to identify points of confusion encountered by the user and then to "walk through" what would help them out.

• Test Example: The user is shown an example of a mundane situation, i.e. a screen shot of a user-account management tool, and then asked to talk through their assumptions, expectations, wishes, etc.

Page 17: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

Assessment Test: This is the most common test conducted.

• When to use: Normally conducted early or midway through the design of the product.

• Objective: This test assumes that the basic conceptual models are decided and determines how well they've been implemented. The test seeks to measure the effectiveness of the implementation.

• Methodology: The user performs tasks while the monitor largely stays out of the way. Quantitative measurements are gathered.

• Test Example: User is asked to accomplish a book renewal.

Page 18: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4
Page 19: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

Validation Test:

• When to use: This test normally takes place close to the release of the product.

• Objective: The purpose of this test is to establish that the product performance meets or exceeds benchmark standards in time and effort required to accomplish a task. These standards are arrived at either through previous tests or educated guesses. This test also measures how well all the pieces of the design work together.

• Methodology: Benchmarks are first established for the tasks. The tasks are then given to users and the resulting completion efforts monitored. The resulting quantitative data is analyzed and timings over benchmark are identified as possible problem areas.

• Test Example: "Access your library account, identify if any books are due soon and then renew them if they are. Benchmark = 1 minute”

Page 20: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4
Page 21: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

Comparison Test: This test compares the users reactions to multiple examples of a tool or implementation.

• When to use: This test can be used at any stage in the design process to compare radically different designs or implementations against each other.

• Objective: This test is used to determine which design is easiest to use and what are the advantages and disadvantages between designs.

• Methodology: This test can be an exploratory test where multiple designs are compared qualitatively. The usual result is an improved product which combines the best of many different ideas. The best results normally come from comparing examples of wildly differing implementations.

• Test Example: "Locate a tutorial on finding scholarly journals on the following library websites."

• Rubin, p. 30-42

Page 22: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4
Page 23: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

Types of Usability Testing

• Hallway Testing

• Remote Usability Testing

• Expert Review

• Paper Prototype Testing

• Questionnaires and Reviews

• Do-It-Yourself Walk Through

• Controlled Experiments

• Automated Usability Testing

http://usabilitygeek.com/an-introduction-to-website-usability-testing/

Page 25: Usability. User-Based Practices Questions Questions Organization Organization Sign Posting Sign Posting Background Background Anderson, Chapter 4

Role of Test Monitor

• Be a good listener

• Build a rapport with the participant

• Be flexible and open to changes in the usability plan

• Maintain a long attention span

• Try not to lead the participant--they need to find the answer themselves!

• Try not to act too knowledgeable--playing dumb can raise some interesting results.

• Try not to jump to conclusions--strive to pick out patterns while not allowing that knowledge to color your interaction with the participant.

http://www.lib.washington.edu/usability/resources/guides/tests#section-2

Rubin, p. 64-72