Background

Our web technology research center, at Florida Tech, has developed a web usability assessment model and supporting toolset that promotes user satisfaction as an integral part of the development of online business applications. This web usability assessment model is an outgrowth of our collaboration with industry in the pursuit of more effective online development efforts. Our web usability assessments have included B2C and B2B e-commerce sites in an international marketplace, the results of which must remain confidential. We have published generic findings, from a global perspective, in IEEE Software (Becker & Mottay, 2001).

The usability assessment model, shown in Figure 1, was developed to identify and measure usability factors that impact a customer’s online experience. The model includes usability factors, which are further decomposed into usability elements (e.g., font size associated with the design layout factor). The model takes into account the user profile such that an assessment is based on the perceived usability of a web site. The model also includes environmental factors inclusive of monitor size, browser type, and modem speed. The goals of the organization may be included, as time-to-market, financial, or other strategic objectives may impact web site development. Many organizations, for example, did not initially comply with accessibility guidelines due to cost and deployment time considerations.

Though not shown, we have expanded these factors into over 100 usability elements that have been used during usability assessments of commercial sites (Becker et al., 2000). A prototype web tool, called the Web Inspector, has been developed for data gathering and assessment purposes. The Web Inspector allows a user to assess one or more pages within a site or across sites, based on how the study has been set-up by an administrator. An assessment is based on one or more usability factors (design layout, accessibility, design consistency, information content, navigation, design standards, performance, reliability, and security) depending on the objectives of the assessment. The tool summarizes the data and allows for customized reports to be generated based on one or more assessments.

One of the significant aspects of this tool is that it is a web-based application. This makes it readily available to be used at geographically dispersed assessment sites. It has an underlying relational database so that historical data can be used comparatively as web sites change.

Current Research Efforts

The usability assessment model has been modified to include visual impairment as part of the user profile data (though more accessibility profile data may be added at a later date). This will require a usability assessment to include usability elements associated with textual, audio, imaging, and others, and this work is still underway. We have also initiated usability work in the area of reading level, as this usability issue may render sites virtually inaccessible to target users especially when English is a not the primary language.

We have recently expanded our usability research to address multicultural issues associated with government and commercial web sites (Becker & Crespo, 2001). The cultural diversity of the student population at Florida Tech has presented an opportunity to study usability from an international perspective. Multicultural usability issues that have been uncovered include language syntax and semantics (e.g., direct translation of text into target language resulting in nonsensical or offensive information, inappropriate hyphenation changing the meaning of the text, error messages not translated into native language, search mechanisms on non-English web sites support only English). We have also identified issues associated with color, symbols, images, icons, text layout, font size and style, as well, as others.

Figure 1: Web Usability Assessment Model

The Web Inspector tool is undergoing a transformation in order to make it a viable tool for usability assessments in terms of the validation of its usability questions, and the appropriateness of metrics generated. We have established a web usability lab at Florida Tech, which will allow us to use the tool by targeted users based on nationality, age, gender, visual challenges, and other profile data.

Three Major Issues Uncovered During Our Usability Assessment Work

Three major issues that have been uncovered during our usability research include: user’s age and design layout, internationalization and design consistency, and information content and accessibility. Each of these will be briefly described.

Age and design layout - The age of a user may impact usability due to visual limitations, typing capability, computing knowledge, and other user profile elements. Visualization of a web site, based on age, may be impacted by font size, color, and type, background color and patterns, use of vertical and horizontal white space, and the position of buttons, labels, images and other web objects, among others. There are other aspects of usability that may be related to age inclusive of navigation, design consistency, and others.

Multicultural issues associated with design consistency – Design consistency ensures that web objects and pages behave the same way within and across pages. It also ensures that web objects and pages have the same look and feel within a web site, regardless of whether there are international versions of it. Our multicultural studies of government and commercial e-commerce sites have uncovered a cultural centricity phenomenon (Becker & Mottay, 2001). The originating web site tends to have a “better” design in terms of performance, design layout, navigation, information content, etc., than translated versions. We have found that translated web sites typically have more graphics than the original site, thus negatively impacting performance. Another design inconsistency is the lack of particular words and phrases being translated from one language to another. Too often, button, links, box, and other web object labels are not properly translated. A web site, for example, may have “search,” “go,” and “cancel” appearing on a non-English web page.

Accessibility and information content – Accessibility requires the availability of meaningful information about the behavior of a web object, and its relationship with other web objects. A web object may be related to another web object in a nonlinear fashion, such that the response of one object impacts another. Visually, this may be understood by looking at the web objects on a page. When used by a visually challenged individual, this relationship may go undetected thus having a negative impact on usability.

To support the accessibility goal, we may have to add information to a web page regarding the usability requirements of each web object (Becker & Berkemeyer, 2001). This information would be encapsulated in the source code, as it is part of the specification of the web object. Because HTML source code only supports a few usability requirements, we have developed an enhanced version of HTML called “Self Testing” Hypertext Markup Language (ST-HTML)[1]. Since ST-HTML is an extension to the HTML language, it is “executed” and behaves similarly to the standard web page.

There are several tags that are proprietary to ST-HTML which allow for definition and enforcement of usability requirements during testing. Because these proprietary tags, properties, and values are not part of the HTML specification, web browsers ignore them. Therefore, ST-HTML employs the use of a custom browser.

For example, let’s say we specified a text box for holding customer comments about a product. The text box has the following usability rules:

· Rule 1: Data entry is optional (the customer may leave it blank)

· Rule 2: Valid data includes letters, digits, and white spaces (spaces are valid data for this comment field though an email address field, for example, would not allow spaces)

· Rule 3: User message is displayed (“Enter your comments here”).

The ST-HTML elements, representing these requirements, are in boldface to show the extension to HTML.

<TEXTAREA name=CommentTextArea rows=5 cols=35 DataType="Text" TextContent="Letters, Digits, WhiteSpace, Other" NumericContent="" DataLength="" Conditions="" DataRequired="No">Enter Your Comments Here</TEXTAREA>

From an accessibility perspective, these usability requirements are made accessible in order to provide meaningful information about a web object. Though not shown in this example, valid and invalid states may be specified in ST-HTML providing additional information about the behavior of a web object.

It is important to note that XML would be a powerful tool to support the addition of meaningful information in source code to support visually challenged individuals and perhaps non-English speaking individuals. XML schemas would provide a standardized mechanism for supplementing source code inclusive of textual descriptions of links, graphics, etc. It would also support the usability requirements concept, which was developed in ST-HTML. A team of students at Florida Tech is currently exploring XML as a viable option to enhance web page source code with this type of information.

References provided upon request.

[1] Note: Our original goal with this research was to provide automated support for web testing early during the development cycle.