UI Style and Usability, User Experience Niteen Borge
User Interface • A user interface is the system by which people (users) interact with a machine. • UI provide a means of: • Input, allowing the users to manipulate a system, and/or • Output, allowing the system to indicate the effects of the users
UI Design Principles • The structure principle. Your design should organize the user interface purposefully, in meaningful and useful ways • The simplicity principle. Your design should make simple, common tasks simple to do, communicating clearly and simply in the user’s own language • The visibility principle. Your design should keep all needed options and materials for a given task visible without distracting the user with extraneous or redundant information.
UI Design Principles (cont) • The feedback principle. Your design should keep users informed of actions or interpretations, changes of state or condition, and errors or exceptions that are relevant and of interest to the user • The tolerance principle. Your design should be flexible and tolerant, reducing the cost of mistakes and misuse by allowing undoing and redoing. • The reuse principle. Your design should reuse internal and external components and behaviors
Key Aspects • Controls for different features should be presented in a consistent manner. • Various features should work in similar ways. • User interfaces should not change version-to-version -- user interfaces must remain upward compatible
Processes • Functionality requirements gathering • User analysis • Information architecture • Prototyping • Usability testing • Graphic Interface design
Some Website UI design • http://havenworks.com/ • http://www.georgehutchins.com/
What is usability? • Usability is the degree to which something - software, hardware or anything else - is easy to use and a good fit for the people who use it. • Generally associated with the functionalities of the product. • Characteristic of the user interface.
Key Attributes • Learnability • Efficiency • Memorability • Errors • Satisfaction
Usability considerations • Who are the users, what do they know, and what can they learn? • What do users want or need to do? • What is the general background of the users? • What is the context in which the user is working? • What has to be left to the machine?
Other considerations • Can users easily accomplish their intended tasks? • How much training do users need? • What documentation or other supporting materials are available to help the user? • What and how many errors do users make when interacting with the product? • Are there provisions for meeting the special needs of users with disabilities?
Discoverability • Is the user ever expected to do something that is not obvious? • Are there hints and tips and shortcuts that appear as the user is using the software? • Is the user at a disadvantage for not knowing certain keyboard shortcuts • Is the learning curve (of hints and tips) skewed towards point-and-click users rather than keyboard users?
Usability Maxims • Know the user, and YOU are not the user. • Things that look the same should act the same. • The information for the decision needs to be there when the decision is needed. • Error messages should actually mean something to the user and tell the user how to fix the problem. • Everyone makes mistakes, so every mistake should be fixable. • Consistency, consistency, consistency.
Designing for Usability • Three principles of design By John Gould and Clayton Lewis • Evaluation methods • Empirical Measurement • Iterative Design
Evaluation methods • Parallel Design • Inspection methods • Card Sorting • Tree testing • Inquiry methods • Task Analysis • Questionnaires/Surveys
Usability testing • Usability testing is a technique used to evaluate a product by testing it on users. • Usability testing focuses on measuring a human-made product's capacity to meet its intended purpose
Goals of usability testing • Performance • Accuracy • Recall • Emotional response
Benefits of usability • Higher revenues through increased sales • Increased user efficiency and satisfaction • Reduced development costs • Reduced support costs
More Examples • http://www.phonetics-ltd.com/ • http://www.flatpakhouse.com/
User experience (UX) • User eXperience (UX) is about how a user feels about using a system. • ISO 9241-210 defines user experience as "a person's perceptions and responses that result from the use or anticipated use of a product, system or service". • UX is subjective and focuses on the use.
History • The term user experience was brought to wider knowledge by Donald Norman, User Experience Architect, in mid-1990's.
What affects user experience? • A diversity of things can influence a person's user experience with a system. • User's state • System properties • Situation
UX evaluation • UX evaluation means investigating how a person feels about using a system. • It hard to evaluate user experience and come up with solid results • Subjective • Context-dependent • Dynamic over time
UX evaluation approach • Goal: Summative (score) or Formative (areas for improvement) • Approach: Objective or Subjective • Data: Quantitative or Qualitative • Granularity: Momentary, episodic, or overall UX • Setup: Lab or field
User Experience measures • Utility: Does the user perceive the functions in the system as useful and fit for the purpose? • Usability: Does the user feel that it is easy and efficient to get things done with the system? • Identification: Can I identify myself with the product? • Stimulation: What kind of experience I am getting from system? • Value: What is its value for me?
UX evaluation methods • Diary methods • Experience Sampling Method • Day Reconstruction Method • AttrakDiff: questionnaire for overall UX evaluation • Ladder interviews