respect to navigability, internal structural characteristics reveal that the US and CA rank highly with regard to these navigability measures, while the UK is seen to be lagging.
In contrast, with respect to nodality, the UK and the US emerged as the clear leaders. In terms of incoming nodality (or authority), the UK scored most highly with respect to the normalized number of external inlinks, and was beaten only by the US with respect to the proportion of pages receiving links. These two were considerably more authoritative in this sense than Canada, which in turn eclipsed the two smaller sites. The US and the UK received links from a greater number of hosts than the other sites, with a smaller proportion of governmental hosts. The UK had far more links from different governments (probably reflecting the NAO’s hosting of a site for an international association of audit offices); the US was lowest here with only 7, perhaps highlighting the somewhat insular nature of US public administration. When it comes to outgoing nodality (hubness), which is a measure of the ‘willingness’ of a site to link to information in other domains, we found considerable variation, with Canada having by far the greatest number of outlinks. New Zealand and then the UK have a significantly higher number of external outlinks when normalized by the size of the website. Although Canada linked heavily outside, the majority of links are within the Canadian government and it was the UK that emerged as linking to the highest number of hosts (over twice as many as its nearest rival, the US), the highest number of different governments (four times as many as its nearest rival, New Zealand) and by far the highest number of audit offices. The US and the UK appear to be the most ‘authoritative’ sites, i.e. the most effective disseminators of information. The UK and New Zealand seemed to be the most effective collectors of information (hubness) from the outside world. Overall, therefore, we might deem the UK the most ‘nodal’ of our audit offices online.
Our comparative study affirms previous qualitative studies, for example in their findings of the superiority of Northern American sites. However, we have done so by using quantitative measures instead of qualitative assessment. Our study has also yielded novel results. By distinguishing between internal and external connectivity, we have broadened our analysis beyond the website itself and have established a first quantification of nodality and therefore how an institution’s website relates to its surroundings.
We believe these metrics offer the possibility to provide a more sophisticated and meaningful evaluation of the web structures of government than any of the existing studies outlined in the first section. When applied at the ‘whole government’ or policy sector level, they offer the possibility to rigorously assess the accessibility of government information along two key dimensions: navigability and nodality. This study represents, as far as we know, the first attempts to quantitatively measure either of these dimensions and the first attempt to apply these techniques systematically to the web structure of government. Because these measures are non-obtrusive, data can be collected relatively cheaply (more so, at least, than any user metrics) without transgressing ethical boundaries or seeking multiple permissions although a web crawler has to be configured in a way that puts no irresponsible pressure onto the bandwidth and availability of information providers . Our aim now is to move beyond the relatively modest research subject of audit offices to larger departments (such as finance ministries or foreign offices) and then to governmental domains.
Figure 3. A comparison of the audit offices according to (i) percentage of hosts from the home country, (ii) percentage of commercial hosts and (iii) number of different countries appearing in the list of hosts.
The next stage for future research will be to compare our structural measures against results of our lab based user study that we just finished and also against user metrics, collected via mystery shopping exercises, opinion surveys and usage statistics, in order to verify that sites or communities which emerge as ‘healthy’ in terms of navigability and nodality also score well when experienced by users.
Thanks to the National Audit Office of the UK and the Web manager of the School of Public Policy, Aaron Crompton, for providing us with data to verify our crawls. We also want to express our gratitude to Vladimir Batagelj and Andrej Mrvar for developing Pajek, their excellent program for large scale network analysis. We would like to thank the Cambridge-MIT Institute for
financial support. This National programme of 1ET100300419).
work was supported research (Information
in part society
by the project
 Accenture (2005) Leadership in Customer Service: New Expectations, New Experiences, The Government Executive Series, April 2005
 ‘Focused Crawling using Context Graphs’ M. Diligenti, F. Coetzee, S. Lawrence, C. L. Giles, M. Gori, in 26th International Conference on Very Large Databases, VLDB 2000, Cairo, Egypt, 10–14 September 2000, pp. 527–534.
 ‘On the Web Structure and Digital Knowledge Bases’ A. Caldas, 2004.