Experts disagree about how many links an online document should contain. A document with a high-link density offers many links to readers. A document with a low-link density offers few.
The following section summarizes the views of three groups of online writing experts concerning link density. I then offer a list of quick tips concerning this issue.
Mark Bernstein (1991) advocates a plentiful but thoughtful use
of links, guided by what the rhetorical situation allows.
Bernstein disagrees with the strategy of restricting the role of links in online documents, as others have advocated. He argues that reader disorientation arises from bad writing, not from interlinking topics. As in any medium, he states, "hypertext may prove unwieldy and inexpressive when used without care and thought" (p. 42).
In addition, Bernstein claims that no convincing evidence exists that interlinked information necessarily disorients the reader or that a sequential presentation prevents readers from getting lost. Thus, he advocates a form of hypertext that depends on "the tension between regimentation and richness, between predictability and excitement" (p. 41).
To guide decisions about the number of links to provide and their placement, Bernstein recommends letting the rhetorical situation (especially the document's purpose and reader needs) dictate one's choices. For example, he recommends that you:
Kushal Khan and Craig Locatis (1998), through their research
on information retrieval using hypertext links, support the notion
of using low-link density in a list format to produce the best
overall results in search performance.
In their study with actual users, Khan and Locatis show that low-link densities displayed in a list format produced the best overall search performance, in terms of search accuracy, search time, number of links explored, and search task prioritization.
In the study, 64 high school juniors and seniors performed six searches of varying difficulty on one of four versions of a hypertext opinion piece on persuasion, subliminal suggestion, hypnosis, and brainwashing. Each version was organized hierarchically with either low- or high-density links displayed in either lists or paragraphs. (The high-density display presented six links whereas the low-density display presented only three.)
The authors suggest the following explanations for students' poorer performance with high-link densities:
Given more choices, students are simply more likely to make mistakes.
When fewer links are displayed, cognitive load is reduced because searching and exploration are more focused.
Patrick J. Lynch and Sarah Horton (1997) recommend using links
sparingly, if at all.
Lynch and Horton, coauthors of the Yale C/AIM Web Style Guide, express concern about Web authors uncritically embracing hypertext linking. They write that "loose links can drive away an audience, dilute the site's message, confuse the reader with irrelevant digressions, and become a continuing maintenance headache for site authors and Webmasters" (p. 115).
Though both navigational and associative links can elicit problems, they argue that associative links cause the most, mainly through their overuse or poor placement.
The authors describe two fundamental design problems with associative links:
Readers assume links have some meaning but too often, links are ambiguous, and readers must follow them to discern their significance. Instead of enhancing the reader's understanding of a subject, a link may "send them to a foreign land without a guide" (p. 116).
Link density tips
The following tips reflect my own bias concerning link density. I lean toward the "less is more" approach.
Remember that every link is a maintenance issue.
Point most links within your own document or Web site.
Why invite your readers to leave your site? They might never return.
Use a lower link density.
Too many links can confuse readers with tangential digressions. You need to guide readers and filter their choices.
Be aware, however, that displaying fewer links might lead to the need for more link layers. Too many link layers can lead to increased error rates and task completion times (Kahn & Locatis, 1998).
If you don't want to interrupt the reader at a certain point,
don't put a link there.
Not everything that can be linked should be linked.
Do provide some links to external resources.
As Jakob Nielsen states: "Linking to material from outside your own site allows you to take advantage of what others on the Web have produced. If you can select the correct links, you can enhance your service thousands of times beyond what you have the capacity to deliver yourself" (Allstetter, 1998).
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Last Updated: May 2, 2001
(c)2000 by Alysson Troffer. All rights reserved. Do not reproduce or redistribute any material from this document, in whole or in part, without written permission.