Reflections on UIR Practical 4&5

Search Engine: Yahoo!

Keywords used: Impact of terrorism on world economy, terrorism on economy, world economy, terrorism, terrorism on economy

Web Results showed the relevant web pages found by Yahoo! Search found in response to users’ search terms. Web Results were generated from the billions of web pages discovered, crawled, and indexed by Yahoo! Search. Within web results you might also choose to see Portable Document Format (PDF), View as HTML, RSS/View as XML, View as XML, Add to My Yahoo! Beta, URL, Cached or More pages from this site. The list of results will include the name of the page, the URL and short description from the page containing your keywords.

Relevance ranking looked at the number of times search term appears in the document, in a ratio with some overall measurement of the document, like length of number of words. The significance of term in the retrieved text was estimated and the hits were given rank or scores that determine the order they were displayed.

Size of hits is 8,910,000 for impact of terrorism on world economic took 0.11 sec. There were often multiple pages of web results. The total number of results found was listed to the right of the section heading. When other users had done searches similar to the user’s searches, Yahoo! Search would list these queries under the search box in “Also Try” which might help narrow down results.

Meta Search Engine: Metacrawler

Web Results showed the relevant web pages found by MetaCrawler in response to users’ search terms were ranked by relevance and eliminate duplicate hits. Refer to figure 8 below. Size of hits was only 56, much lesser compared to using search engine. The results returned from these engines include commercial (sponsored) and non-commercial results. MetaCrawler was designed to identify the intent of a user's search. Web Results were generated from combined results found in different search engines which users could see the URL with short descriptions showing the keywords and url of the source found. Beside Preferences and Advanced Search, there was a click option for exact phrase to display results keyed in the search box. Are you looking for? would provide additional topics related to the research keywords. This was helpful in providing additional help especially when users were uncertain about what to find on. Recent Searches was used t o rack and display 15 most recent searches for easy references on past search keywords.

Subject Directory: Galaxy

From the keywords of ‘terrorism on economy’, Galaxy found 407 directory matches, mainly the sub-categories are business and economy for each country. For example Community > World Communities > Asia > Countries > India > Business and Economy. Refer to Galaxy would also show sites that match with titles and short written description. These sites actually paid to submit their site to the Galaxy Directory. Galaxy offered multiple service plans in which editors will manually review the submission to ensure listings in Galaxy were well organized and presented in a logical and intuitive fashion. Theses sites could be accessed by clicking on the telescope. The relevance was actually ranked with how many stars given to this site.

Search Engine

Search engines used software "bots" to scout the Web and assemble databases or indexes of Web pages. When a query at a search engine Web site, input would be checked against the search engine's keyword indexes. The best matches were then returned as hits. Basically a search engine had two parts: A "robot", "crawler", or "spider" that traveled to pages on the Web and assembled an expansive index, and a program that received search request, compared it to the index entries, and returned with results.

Limiatations of Search Engine
The percentage of pages effectively indexed by search engines. Moreover, the overlap between different search engines was quite limited. This was due to the continuous expansion of the World Wide Web (WWW). erroneous answers. Some of the results returned by Yahoo! Search were links that were not available any more, or unrelated to keywords entered. The redundancy of results was another problem of available search engines.

Limitations of Meta Search
Usage was limited primarily to simple queries. It was difficult to conduct a complex search because each search engine had its own search features. Other limitation of this meta search engine would be returning of a limited number of results that do not represent the totality of results from any source engine, little or no field searching is available.

Limitations of Subject Directory
One of the major disadvantage of using directory would be the hierarchical arrangements may be arbitrary. The editors who organized the directory may defer from another directory. The ability to search Yahoo! and most other directories by keywords solve this problem of arbitrary hierarchical arrangements. Another drawback was that selecting, rating and categorizing Web Pages took a lot of time, so directories tend to me less up to date than search engines databases, which are constantly updated by computer programs that automatically gather new Web Pages. The third disadvantage would be subjectivity of rating and annotating resources because it differs between individuals.

There was no hard and fast answer to whether a search engine, meta search engine or subject directories would be a better choice. A lot depends on the personal preferences of the user. Some people like directories because the user can control the search pattern, varying the path through the descriptors if another descriptor looks promising.

Directories allow users to browse and to be more vague or general in their search term. Directories are generally better at finding general information and should be where user should start. Use meta search or search engine instead to find something more specific.

Search engines are not always as easy to use as directories, but sometimes they can find sites that have not been indexed in a directory. Even search engines cannot keep up with the explosive growth of the Internet, however, so more than one might have to be used to find specific information. User must take note that carefully constructed searches of the major search engines often return more relevant results than those delivered by many meta-search engines

Search engines leave the searching pattern to the computer program and can be used to find more specific resources. Many of these search engines maintain separate pages for simple and advanced searches. Don't be afraid of the advanced searches because usually it just means there were more options to use. Thus results would be frequently better.