Usability

presented by the OSU Libraries’ u-team

The Usability Team

• Consultation

• Education

• Usability tests

Why?Usability is about building web sites based on user feedback and input and with the users' needs and goals in mind.

We want to reduce confusion and make it easier for users to accomplish their goals on our site. The payoff is in lower support costs and a better user experience.

– Bad intranet/B2B Web design cost $50-100 billion per year in lost employee productivity

Save staff time

Grow our user population

Improve OSU Library’s image

Participation in research and development

Usability Definition

Usability relates to the users experience of a product or website.

Usability is defined by the following five quality attributes.● Learnability● Efficiency● Memorability● Errors● Satisfaction

Learnability

• How easy is it for users to accomplish basic tasks the first time they encounter the design?

Efficiency

• Once users have learned the design, how quickly can they perform tasks?

Memorability

• When users return to the design after a period of not using it, how easily can they reestablish proficiency?

Errors

• How many errors do users make, how severe are these errors, and how easily can they recover from the errors?

Satisfaction

• How pleasant is it to use the design?

User centered design

User-Centered Design

• In broad terms, user-centered design (UCD) is a design philosophy and a process in which the needs, wants, and limitations of the end user of an interface or document are given extensive attention at each stage of the design process.

• User-centered design tries to optimize the user interface around how people can, want, or need to work, rather than forcing the users to change how they work to accommodate the system or function.

• Four essential activities in a user-centered design project:

– Requirements gathering - Understanding and specifying the context of use

– Requirements specification - Specifying the user and organizational requirements

– Design - Producing designs and prototypes

– Evaluation - Carrying out user-based assessment of the site

How to Develop User-Centered Web Sites

• Involve users from the beginning

• Know your users

• Analyze user tasks and goals

• Don’t settle on a final direction too soon

• Test for usability—repeatedly!

Methods for Achieving User Centered Design

• The word "usability" also refers to methods for improving ease-of-use during the design process.

• Usability can be measured objectively via performance errors and productivity, and subjectively via user preferences and interface characteristics.

• Examples of usability methods

– Ethnographic Study

– Scenarios and Persona's

– Task Analysis

– User testing

– Heuristic evaluation

– Card Sorting

Ethnographic Study

• Observing users in the field. – Interviews– Questionnaires & Surveys

• Collecting artifacts and data

Scenarios and Personas

• A "persona" is a fictional portrait based on a typical person who embodies key user characteristics. This portrait can include demographic information, attitudes, needs, motivations, as well as personal details.

• Scenarios are a vocabulary for coordinating the central tasks of system development. Scenario may include text, video, pictures, story boards, etc

Task Analysis• Task analysis is a method that evaluates how people actually accomplish things with

software.

• Through observation and interviews with users, an analyst determines a set of goals belonging to the target user. Then, a set of tasks that support these goals is determined.

• The highest priority tasks are decomposed into their individual steps. The analyst then suggests ways to make the task more efficient or suggests new tasks which more effectively support the goals.

Think-aloud User Testing

• A method used to gather data in usability testing ( not focus groups!)

• Participants are asked to think aloud as they are performing a set of specified tasks.

• This enables observers to see first-hand the process of task completion (rather than only its final product).

Heuristics Inspection

A systematic inspection of a user interface to judge whether each element of the interface follows established usability principles.

1.Visibility of system status

2.Match between system and the real world

3.User control and freedom

4.Consistency and standards

5.Error prevention

6.Recognition rather than recall

7.Flexibility and efficiency of use

8.Aesthetic and minimalist design

9.Help users recognize, diagnose, and recover from errors

10.Help and documentation

Card sorting

• Card sorting is a categorization method where users sort cards depicting various concepts into several categories.

• For example, you might want to determine how users would group various functions. You'd use this information to place the functions on various menus of a user interface.

Prototypes

• Prototyping models your final product and allows you to test attributes of a product even if it's not ready yet. You simply test using your model.– Wireframes: a skeletal version of a product

that represents navigational concepts and page content.

– Paper prototyping: sketches or images of a product

• Usability team

• Web designers

• Content providers (you)

• Web programmers

• Graphic designers

• LAMP

U-Team Services

• Comparative testing: LibraryFind/GoogleScholar/Libraries Website

• Formal usability study: Libraries Website• Inhouse testing: LibraryFind, Oregon

Explorer• Data analysis: Oregon Explorer

bibliography

• http://www.useit.com/alertbox/20030825.html

• LITA Regional Institute User Centered Design Workshop January 19, 2006

Explore more!• Jakob Nielsen http://www.useit.com/alertbox/20030825.html