Library Research Skills
How to use search engines
To use a search engine, you submit relevant words to be compared to terms in the index using a form. Any matching results are then displayed.
As your term may describe many resources, searches often return thousands of results. To make these results easier to interpret, they are ranked in order of relevance. This may be based on the number of times your search term appears on a web page, where it appears in the page or how many other sites link to that page.
When to use search engines
For lots of information
As search engines have such large indexes, you are likely to find many resources on any given topic. This is good when looking for lots of information, but the list can be daunting to work through.
For a fairly specific information need
Again, because search engines index almost every word on a web page they work well for finding very specific information. For example, a search on "political parties in Germany" would be likely to produce more relevant results than a more general one for "politics".
For details of organisations or people
This is a very specific information need and as search engines index full-text they perform well for this type of query.
Exercise
Have a brief look at Google. Try entering some search terms and rate how relevant the results returned are.
Metasearch engines
Metasearch engines allow you to search across multiple search engines simultaneously. This can save you time as you don't have to search each individually.
How to use metasearch engines
To the user, a metasearch engine works in exactly the same way as a search engine - you simply enter a search term. However, rather than just searching in it's own index, the metasearch engine sends your query to several search engines and compiles the results.
Despite searching across many services, a relatively low number of results are typically returned. This is because the results are generally limited to only the most relevant from each service. In addition, resources found in more than one search engine are only listed once.
When to use metasearch engines
If you have a specific information need
As with search engines, metasearch engines are good for finding specific information because they search against an index of the full-text of resources.
If you want to save time
Using a Metasearch engine take less time than carrying out the same search in each search engine individually.
If you want to increase the range of web resources searched
As each search engine index will contain a slightly different set of resources, using a Metasearch engine can increase the proportion of the web covered in a single search.
Exercise
Carry out a search using the Metasearch engine Ixquick . Notice that the search services used are listed at the top of your results
Classified directories
What are classified directories?
A classified directory is a list of web resources arranged by subject.
As they are compiled manually (by human beings), rather than by software, classified directories generally contain only high quality resources. However, beware of directories funded through advertising who may include a resource for commercial reasons.
How to use classified directories
Classified directories can be browsed by subject and/or searched by keyword. When searching, your keyword is compared to the entry in the directory, not the resource itself (as for search engines). As such, directory searches generally return a small number of highly-relevant results.
When to use classified directories
If you have a general information need
Classified directories are a good place to start if you want to browse in a particular subject area. Directories group similar resources together, enabling you to see resources in the context of a broader subject.
If you want to browse structured information
The resources in classified directories are structured into a subject hierarchy allowing you to browse in a similar way to browsing through books on a library shelf.
If you want to find higher quality information
As resources in classified directories have already been evaluated, they should be of a high quality.
Examples of classified directories
Yahoo! or BUBL
Exercise:Take a look at Yahoo! . This is a searchable and browsable index of the internet resources organised using Yahoo's own subject headings.
Subject gateways
A subject gateway is simply a classified directory for a specific subject.
Many subject gateways are run by librarians who are subject specialists. They use established classification schemes to evaluate web resources in the same way they would for traditional resources.
This ensures the material listed is relevant and up to date. However, the time required to evaluate resources in this way means that gateways generally list a relatively small number of resources.
How to use subject gateways
Information is retrieved from subject gateway by browsing or keyword searching. Again, when searching you are not searching the resources themselves, only the record describing that resource.
When to use subject gateways
For general information on a specific subject
A subject gateway performs best for general queries for the same reason a classified directory does - a very specific term is less likely to be included in a catalogue record.
For access to structured, high quality information
Again, like classified directories, the resources subject gateways have been organised to enable structured browsing through subject hierarchies.
Take a look at some of the subject gateways available via the Resource Discovery Network
Finding People
While there is no single directory listing everyone on the internet, there are ways to find personal contact information.
Institutional web sites
University, college and company web sites often publish directories of personnel that can be searched or browsed.
Directory services
White and yellow pages service for searching for email addresses, telephone/fax numbers and company web sites.
Search for email addresses, business phone numbers and addresses world-wide.
An online version of UK directory enquiries
An online version of Irish directory
Conclusion
In this section, you've been introduced to a number of services that allow you to browse or search the internet.
You have:
- Gained experience in using the web to search for information
- Considered which search tools are most effective for finding different types of information
These tools should help you to find most types of information quickly and simply. However, always watch out for new services that might prove useful.
Next Page - Starting your Search
Copyright (c) 2005 by Susan Kelly, Wexford County Library Service.
Adapted and modified (5th December 2005) from TILT, Texas Information Literacy Tutorial. This material is subject to the terms and conditions set forth in the TILT Open Publication Licence. (the latest version is presently available at http://tilt.lib.utsystem.edu/yourtilt/
