User goals and web site navigation implications for the designers of sitemaps

One of the challenges confronting web site developers is to provide effective navigational support. Research in human-computer interaction (HCI) has done much to improve the general area of Web usability and supplemental navigation tools such as sitemaps are frequently included on web sites. However, due to a lack of empirically based guidance for designers, a proliferation of sitemap designs has evolved leaving both designers and users confused about the role and value of these navigation tools. The limited guidelines that do exist are either based on extrapolation of navigation research into pre-Web hypertext systems, or on empirical studies that use methods and measures that may not take into account the particular nature of sitemap tools. A common assumption in both the application of previous research and recent empirical studies is that sitemaps are selected by users who wish to search for something specific. However, users have a variety of goals, needs and motivations when interacting with web sites. Some users can express exactly what they want; others are vague and unsure of their goal. Goal specificity is an important factor in understanding how users interact with web sites, however it has not been a major consideration in recent research. This research project investigated the influence of goal specificity on how users navigate through web sites in order to better inform the design of sitemap tools. The thesis commences with the development of a framework describing Human- Web Interaction which provided a structure for the project by clarifying the role of user goals and navigation strategies in the context of previous theory. Three studies investigated the research problem. The first study involved a number of surveys which explored commercial design practice as well as the expectations of users regarding the purpose and design of supplemental navigation tools. The findings from this study suggested a relationship between certain types of information goals and the selection of search and sitemap tools. In addition, the results provided an insight into the tension between user expectations and current sitemap design practice. The second study examined the relationship between goal specificity and the use of supplemental navigation tools such as search tools and sitemaps. An experiment tested a hypothesis relating goal types to the use of specific navigation tools. The results suggested that when a user selects a sitemap they are more likely to have a loosely defined goal and are interested in general and metainformation about the web site. The third study explored the relationship between goal specificity and the strategies that users employ when browsing web sites. The results identified several patterns of behaviour for each goal type, confirming that goal specificity influences user behaviour when browsing web sites. The thesis concludes with a synthesis of the findings with implications for the design of sitemap interfaces and the design of future empirical studies into web navigation, particularly studies which aim to develop or validate design guidelines for navigation tools.