Persuasive Technology: Using Computers to Change What We Think and Do

Web credibility, like the general concept of credibility outlined in Chapter 6, is made up of two dimensions: trustworthiness and expertise (Figure 7.4). When a Web site conveys both qualities, people will find it credible. When it lacks one of these qualities, credibility will suffer. In essence, when people perceive a site to be unbiased (or biased in a way that fits the user s worldview) and knowledgeable factors underlying trustworthiness and expertise they also will view it as credible. This is the same general formula introduced in Chapter 6.
A Web site will have more credibility if it highlights the people or organization behind the content and services it provides.
People rely on perceptions of trustworthiness in evaluatingWeb credibility. Table 7.2 shows the trustworthiness-related elements from the Stanford studies that were reported to boost credibility the most. As Table 7.2 shows, elements that allow people to contact a Web site source increase perceptions of Web credibility. And the more direct the contact, the better. Listing an organization s physical address boosts credibility dramatically. Listing a phone number also has a major impact. These two elements rank significantly higher than listing an email address. [23 ]Why? The study data do not provide an exact answer, but it seems these elements may show more clearly that real people are behind the Web site people who can be reached for questions, comments, or...