Instability in Search Engine Results: Lessons Learned in the Context of Horizon Scanning Applications

Horizon scanning, the systematic search for information to identify potential threats, risks, emerging issues and opportunities, has become an increasingly important part of strategic decision making. Although horizon scanning has its roots in the pre-electronic information era, it has blossomed with the availability of Web-based information. Dedicated analysts responsible for scanning the horizon make frequent use of search engines to retrieve information. Regrettably, the results yielded by popular search engines are often inconsistent and redundant. Thus, post processing heuristics have to be employed to select the most relevant data. This paper focusses on the first steps of this process, and analyses the result counts provided by different search engine interfaces in response to a set of queries meant to gather information about new and emerging trends.