Usability Testing: information about the techniques and processes for evaluating software usability.
Recommended Books

Making use of user research
Cooper Interactive: User research can be roughly broken down into two types: usability testing and ethnographic field research. Many people are already familiar with usability testing, and many companies make use of it during development. However, ethnographic field research can yield valuable results for improving products that can't be easily measured by usability testing. (2001-09-16)

Guerrilla usability
Builder.com: The most important design elements to test are navigation; labeling of inputs, categories, links, and buttons; searching; and multistep processes such as shopping or registration. Anytime you do something unconventional, test it. Innovation is critical to advancing usable Web design, but don't turn your visitors into unpaid test subjects. Test in the safety of your own garage with willing subjects. (2001-09-16)

Fly on the Wall
IBM developerWorks: For developers to make products that delight customers, they need adequate information about who exactly the customers are and what their requirements are. The User-Centered Design (UCD) process provides numerous options for gathering both customer and user input, with wide variation regarding the time involved, labor required, overhead costs, and validity of the information collected. The "Fly on the Wall" (FOTW) technique is a low-cost, low-overhead method of collecting valid customer data. The method is illustrated here through a pilot study that used first-hand, unobtrusive observations by UCD practitioners to collect valid customer data in a timely, cost-effective manner in collaboration with development and marketing staff. (2001-09-02)

The Usability of Usability
An interview with Jared Spool, Founding Principal of User Interface Engineering. According to Spool: "Usability is not usable!  It doesn't work.  It doesn't produce the results we promise it will.  And we get angry when people stop paying attention to us. As a profession, we need to spend a lot more resources on basic research.  We need to stop thinking that there are pat, one-size-fits-all solutions to every problem.  And we need to align ourselves with the business goals more directly.  We need to make our own work usable." (2001-07-29)

A Comprehension-Based Model of Web Navigation and Its Application to Web Usability Analysis
CoLiDeS, a comprehension-based cognitive model of Web navigation, offers a theoretical explanation of the impasses users so often encounter during information search and retrieval from the WWW, and also identifies the determinants of success cases. In this model, acting on a single Web page screen object is regarded as the outcome of a multi-step process: (1) parsing the current display containing up to about 200 screen objects into five to ten top-level schematic objects, (2) focusing on one of these top-level schematic objects, (3) comprehending and elaborating the screen objects within the focused-on area, and then (4) selecting one of the actual screen objects as the target for the next action, the object whose representation bears the highest degree of semantic similarity to the user’s goal. (2001-07-22)

GNOME Usability Study Report
A report on the results of a baseline usability study of the GNOME desktop conducted by a Sun's GNOME usability staff in Menlo Park, California during the week of March 13-16, 2001. Gnome is a graphical user interface (GUI) for the Linux operating system. The report gives detailed findings of the study and makes 32 design recommendations. The study found that GNOME's dispersed development process should be transparent at the user level but it currently shows through. This results in confusion for the user who is confronted with inconsistent terminology and user interfaces, multiple ways to accomplish tasks, and information that is not organized intuitively, requiring the user to manipulate similar information in separate locations. The user is also presented with overwhelming amounts of detail and complexity, all displayed at the same level. (2001-07-22)

Handbook of User-Centred Design
This handbook on user-centred design is intended for those responsible for commissioning or carrying out usability work during the development of interactive systems. (2001-04-24)

Testing E-Commerce Systems: A Practical Guide
IEEE Computer Society: This article provides a quick and practical introduction to testing medium- to large-scale transactional e-commerce systems based on project experiences developing tailored solutions for B2C Web retailing and B2B procurement. Typical of most e-commerce systems, the application architecture includes front-end content delivery and management systems, and back-end transaction processing and legacy integration. Aimed primarily at project and test managers, this article explains how to establish a systematic test process, and test e-commerce systems. (2001-06-17) 

A Simplified, Unified Measure of User Experience
We have many techniques for evaluating our designs—from expert reviews to field trials. But what we lack as an industry is a simple metric that can be used to track our progress and, most importantly, to report our progress in a simple fashion so that our non-HCI, non-UEE colleagues can fully appreciate the impact of design changes on users. In this paper, I present a methodology for measuring User Experience that lends itself to a simplified, unified measure that is easy to understand, remember, and communicate. The User Experience Score is a visualization of objective (performance) data combined with subjective (perceptions/preferences) data that provides a memorable, quotable, trackable measure of User Experience. (2001-06-10)

An Integrated Method for Evaluating Interfaces (pdf)
When we added heuristic evaluation to our expert analysis method, we found that it worked well in our interdisciplinary environment, but that its recommended prioritization strategy (which ranks problems according to severity) has some limitations. Specifically, it does not address how much it will cost the developers to fix the problems, nor does it adequately capture the distinction between high-level (global) and low-level (specific, screen-level) problems. To address these limitations, we developed a method that integrates user research, heuristic evaluation, affinity diagramming, cost-benefit charts, and recommendations into a report that others can use to plan both short and long-term improvements. (2001-06-17)

How Do Your Users Really Use Your Site?
The paper describes a new approach to usability testing that integrates state-of-the-art eye tracking techniques with traditional interviewing methodology. This technique revealed that on the test site, both success rate and confusion rate were high for experienced users, indicating that they could succeed in doing simple tasks but had difficulty using the site. The high confusion rates suggest that wording or organization of the menu is unclear. One would expect confusions to drop with increased familiarity, but this was not the case. For the experienced users, confusions were highest toward the end of the study. All regions of both home pages were noticed by most users. The text of the customer service home page captured quite a bit of attention, suggesting that important information placed here would be seen by both new and experienced users. The large number of extra menu clicks and extraneous page links suggest that users were not using the site in optimal ways. The menu clicks may have been caused by a number of factors, including failure to understand the categories, absence of desirable categories, or hierarchical structure of the categories. The traversing of extra pages was probably related to misunderstandings about menu items. Users tended to click on a menu item, open a page, and then return immediately to the menu in order to select another item. The combination of eye tracking with in-depth interviewing produced strong corroborative results. (2001-06-10)

Apply Usability Methodologies in Intranet Information Architecture
Intranet Journal: Over a series of five articles, I'll use a real project example to demonstrate how we applied comprehensive Usability theories and methodologies in the development of the information architecture for an intranet. Our first method of gathering data for the project was a stakeholder analysis. The purpose of the stakeholder analysis was to develop a better understanding for project expectations and scope, to learn more about the organization, and to gain a general understanding about the end users. (2001-06-10)

NetRaker Experience Recording
A Web-based remote-research application that enables companies to observe and interact with their customers, partners and/or employees by empowering their researchers to remotely view and record their users' computers. By connecting through the Internet or via intranets and extranets, researchers can view their users' desktops and chat in real time. (2001-06-03)

Usability Levels - Three Ways to Care for Usability
SAP: All three levels of usability work are needed for developing usable applications. Technical prerequisites and style guides create the fundament on which usable applications can be built, but do not guarantee them. Only the "user-and-task" level ensures that a development team will really end up with a usable application that serves the needs of its users. (2001-04-22)

Usability Makes a Comeback
ClickZ: Once you've lost a customer on your Web site, you've lost that customer for good. This happens for many reasons: faulty or ambiguous navigation, bad interface design, long download time, incompatible technology, and so on. What can you do about it? The answer is simple: Find out what your site visitors want your site to do. The earlier you discover their needs, the better. To make it easy for you, I have created a Usability Checklist that can be used to test your site before launch. (2001-04-22)

Usability Testing Basics
ClickZ:  About a year and half ago "Web development was almost always done under ridiculous time constraints, and usability testing was seen as an advantageous but unnecessary step in developing a site. Even when sites were tested, there was no time to incorporate learning from the tests before launch. Since then, the industry has come a long way. Usability testing is now recognized as a necessary, if not integral, part of Web site development. As the industry matured, three simple truths emerged:" (2001-04-15)

Usor: A Collection of User Oriented Methods
This web site contains descriptions of different user oriented methods. These are not exhaustive descriptions. They are rather short summaries with references to more thorough descriptions of these methods. The purpose of this web-site is to encourage the usage of user oriented methods in both industry and research projects.  (2001-04-15)

The Race is On
E-commerce Guide: Want to be able to determine what visitors encounter when they visit your site? Then put together this easy usability test. Here are the ingredients: two computers; your site and a competitor's site; two Internet users of equal dexterity; a shopping list; and a timer. Set your users up at separate terminals and arm them both with the same shopping list. Don't put too many items on the list but make sure there is a good mix of products that include non-brand (any black sweater) and specific items (Calvin Klein's cK Be cologne). (2001-03-25)

Usability.gov
This site is designed to provide current and accurate information on how to make Web sites and other user interfaces more usable, accessible, and useful. Information is provided by the National Cancer Institute (NCI), the federal government's principal agency for cancer research. The site also links to a variety of quality Web sites and resources on usability, accessibility, and related topics that exist in the field. (2001-03-11)

Success Rate: The Simplest Usability Metric
Jakob Nielsen, Alertbox: "In addition to being expensive, collecting usability metrics interferes with the goal of gathering qualitative insights to drive design decisions. As a compromise, you can measure users' ability to complete tasks. Success rates are easy to understand and represent usability's bottom line." (2001-02-18)

Heuristic evaluations vs. usability testing
Human Factors International Newsletter: According to the brief article the results of 3 recent studies show that in heuristic evaluations: "...36% (about 1/3) of identified problems were actually usability problems (hits). Some of these problems were serious and some were trivial. The heuristic evaluators missed identifying about 21% of the problems that users had. Finally, about 43% of the "problems" that were identified by the heuristic evaluators did not turn out to be problems at all." (2001-02-18)

Hail to the usability test
Poor design makes us feel like idiots. We blame ourselves. But Nielsen gets us off the hook: "If many people make the same mistake, the conclusion is not that people are stupid but that the design is wrong." And you can't change people. We're a constant, according to Nielsen. Designers typically try to fix people, with training or unfathomable manuals. But it never works. (2001-01-28)

Why You Need to Test Your Web Site with Real Users
Webreference.com: "The ultimate purpose of your Web site should be to help your visitors find the information, product, or service that they want, quickly and painlessly. Professionals of all kinds find it difficult to put themselves in the shoes of ordinary users, so it is essential to ask users what their problems are. Although running usability tests will cost a few thousand dollars, an unusable commercial site will lose far more than that by driving away visitors." (2001-01-14)

Measuring User Experience
Webtechiques: This article defines and describes the best practices for using various techniques for designing and evaluating Web sites. The techniques include usability testing, contextual inquiry, heuristic evaluation, and focus groups.  (2001-01-14)

20 Tasks in Ecommerce
This page lists 20 user tasks that can be used in usability evaluations. The tasks focus on what users need to do with most e-commerce sites. (2001-01-14)

When Nielsen Speaks . . 
WebTechniques.com: An interview with Jakob Nielsen in which he points out that: "In traditional commerce, first you buy a microwave, or a VCR, or an Excel spreadsheet. By the time you've discovered that a product is too difficult to use, the manufacturer is laughing all the way to the bank. On the Web, if a site or product is too difficult, the user's reaction is to leave. The Web reverses the user experience and transaction process. On the Internet, ease of use comes first and transfer of money comes second. Revenues on the Web are determined almost completely by usability." (2001-01-07)

Are you ready for usability?
The Other Media: This article provides some suggestions about implementing usability testing in an organization. It advises "Be opportunistic! If you find yourself with a browser and real live human being, cajole them into a quick usability test - even a 5 minute test may throw up great improvements. Before you know it, you'll be designing tasks, working with strangers and accumulating real data to back up all your great ideas." The article contains a checklist usability factors.  (2001-01-07)

Collecting Feedback About Your Website's Search Interface
Internet.com, Jakob Nielsen and Kara Pernice Coyne: "It's crucial for websites to provide search interfaces that are available, simple, and productive. This article gives basic instructions about how to test your website's search interface for usability." (2001-01-07)

Good Grief! The Highs and Lows of Usability Testing
WebReview: According to this article" "When team members pour their heart and soul into a project, they become heavily invested in the results of their effort. As it becomes clear that changes need to be made, there's a very real grief process involved in letting go of the current design and moving toward a better product. Teams need to work together to process both the information and the emotions that usability testing produces." The author provides some practical advise on dealing with the emotional reaction to the results of usability testing.  (2001-01-01)

EULER evaluation: a study in search engine usability
This site contains a reports for three different usability inspection techniques: Cognitive Walkthrough, Usability Heuristics and Usability Testing with Evaluators. It's an interesting example of documenting the types of findings using these inspection techniques. (2001-01-01)

More Usability Testing