Scent Trails: Integrating Browsing and Searching on the Web Christopher Olson et al. Blake Adams November 4, 2003

Information Location Methods Browsing –View pages one at a time, navigation via hyperlinks Drawback –Inefficient, relies on browsing cues Benefit –Useful where keywords are nonexistent or unavailable

Information Location Methods Searching –Enter a search query into a search engine, choose sites from ranked list of results. Drawback –Often returns inappropriate results, loses important context. Benefit –Identifies pages containing specific information quickly. –Searches are tailored to users specific needs.

Information Location Methods ScentTrails –Automatically high light hyperlinks to guide users toward search results while still allowing conventional browsing. –Degree of highlighting based on ‘Information Scent.’ –Considers search and browsing cues together, user can make informed navigational decisions and locate content matching complex information goals.

Scent Trail Goals Based on information scent developed in the context of information foraging. –How users interleave directed structured behavior (searching) with opportunistic and unstructured behavior (browsing). The goal on ScentTrails is to assist browsing by adding new supplemental cues tailored to the needs of individual users.

How it Works User inputs a list of search terms into an input box, these keywords represent the user’s partial information goal. As browsing/search continues, this box can be modified, and ScentTrails will update dynamically by highlighting existing links that best satisfy the information goal. ScentTrails also considers distance to relevant pages, discounting the value of more distant pages accordingly.

Technique Identify pages that match the user’s partial information goal. Determine distance to desirable results, weigh based on number of clicks necessary to reach goal.’ Weigh fonts of links based on results.

Algorithm

Evaluation Based on a crawl of Used 12 Test Subjects who were assigned 8 searching tasks. Search Options: –Browsing –Searching –ScentTrails –ShortScent (result pages only crawl neighboring pages) Each Test Subject completed each task only once - a set of 2 tasks with each method. These methods were rotated from user to user.

Tasks Performed 1.Find a copier with recyclable toner 2.You have a business at home and you want a copier with photo support. 3.Find a copier with glossy print capability. 4.Find a digital, black & white copier that supports rotation. 5.Find a copier with remote diagnostic technology that can do at least 80 copies per minute. 6.Find a 400 dpi copier with a counterfeit deterrent system. 7.Find a black & white machine that supports scan, fax, print and copy with collation. 8.Find a 5 to 20 cpm (copies per minute) copier with photo support.

Results/Analysis Average task completion time for each task/interface pair, with standard error.

Results/Analysis Average task completion time for each of the interfaces combined across tasks, with standard error.

Results/Analysis

Interviews –Interface Preference: 10 out of 12 preferred Scent interfaces. Dissenting subjects declined to state a preference due to lack of experience –Several Subjects remarked on how the Scent interface allowed them to narrow down some aspects of the task with keywords, while honing in on the other aspects of browsing. –Highlighting: Highlighting method was praised for making searches more efficeient, but criticized ambiguity of textual sizing.

Highlighting options explored