Do your links stink? Techniques for good Web information scent

Bulletin of the American Society for Information Science & Technology, Jun/Jul 2002 by Withrow, Jason

If someone tells you that your website stinks, my advice is to ask them first if it is a good scent or a bad scent and what they thought of the scent quality. You may get an odd look in return, but eventually they will realize you aren't joking. But what scent does a website have? How could a website have a smell? Well, this scent is not a smell that is detected with the nose; it is an information scent, based on our mental associations between concepts.

In an information space like the Web, the goal is to get from one place to another, from here to there. The Web is vast, however, and spatial notions of up and down, right and left do not apply. About the only movements possible on the Web are from general to specific (when browsing through a website hierarchy), from one website to another following a link, or direct access using a search engine. In all these cases, but especially when browsing, visual and verbal cues are required to let us know that we are on the right path to the desired information. These cues are the pieces of information scent that we are following, and we choose the cues with the best likelihood (the strongest scent) of getting us to the desired destination.

An example will help clarify how information scent functions in our use of the Web. Perhaps you are visiting an e-commerce website that carries a wide variety of products. Your interest is in purchasing a movie in DVD format. Looking at the navigation bar for the website, you notice a number of different labels for the links. One link is labeled "Films," which seems more closely related to your desired item than the links labeled "Music" or "Software." In this situation the scent is stronger for the "Films" link, because conceptually that term is closer to the DVD movie than the other two labels. If you were interested in buying a movie soundtrack, though, the decision is not as easy to make. This problem arises because both "Films" and "Music" seem plausible labels. The scent is no longer distinctive. Which path should you choose?

Exploring Scent

Much of the work on information scent has come from researchers in the field of human-computer interaction (HCI), with Xerox's Palo Alto Research Center generating a significant portion of the research in the area. In exploring information scent, these researchers draw on theories of how humans locate information, including information foraging theory. This theory views humans as informavores, continually seeking information from our environment. In a sense we are foraging for information, a process with parallels to how animals forage for food. For both human and animal there are cues in the environment that help us judge whether to continue foraging in the same location or to forage elsewhere. On the Web poor information scent may be one cue that leads a person to leave one website and visit another, because it is unclear where to start looking on the current website and there is also uncertainty whether the effort expended in looking will be justified.

The mechanisms supporting information scent likely draw on the semantic networks that are unique to each individual. We build these vast networks of interconnected concepts from our experiences. The connections between nodes differ not only in terms of distance but also in strength, both of which represent our understanding of the concepts and their interrelationships. Each label or other visual cue on a website activates nodes in our networks that then activate connected nodes in a spreading activation pattern. As the activation spreads it weakens, so that concepts further away from the point of origination receive less stimulation.

Based on these patterns of activation we make our best judgment concerning the link to click when browsing. The process of activating the nodes in the networks and choosing the best option appears to be mainly preconscious, as decisions about where to click next can be made without conscious deliberation if the scent is distinct. Unclear scent, however, or multiple labels with equivalent scent for the desired content will often require conscious deliberation.

The Quality of Scent

How do you know if your website has good information scent? If a user is browsing the website, scent is good if that individual navigates to the desired content simply by choosing the best link at each level of the website. If a search facility is used, the results page should either list the desired page or a page in the same section of the website with sufficient information for the user to make an informed judgment about which link to click. When the users search and don't find the desired content but find something related, the hope is that local navigation on the related pages will provide enough scent for them to browse to the desired page.

There are also a number of behaviors and emotions that indicate scent is poor. If a user is indecisive, moving the mouse between two or three links in the navigation bar and not making a decision, it is very likely that the scent is unclear. The labels probably seem equally good, or perhaps none of the links in the navigation bar seem especially promising, but those two or three are the best options available. This highlights the need for labels to provide clear, distinct scent, suggesting not only what content is found under them but also what content is not found under them.