Library Ebsco Discovery Service is set up to enable keyword searching initially, but there are many limiters available on the results page. A "limiter" is a tool that narrows down a large number of results to something more manageable. EDS often brings up thousands of citations. This is a problem because:
1. No one wants to go through thousands of results.
2. While the EDS engine ranks the results by relevance, this is based on a computer algorithm that may or may not get it right. So the first page of results may not contain all of the best results.
3. Large result sets tend to be broadly focused. Limiters allow you narrow your focus, which is almost always a good thing.
Limit to Source Type :
Here is an example to show the value of limiters. We search on "climate change" AND "polar bears"
With 29,424 results, we have a problem. How can we reduce the number without eliminating useful resources?
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Let's first limit to scholarly articles. That eliminates books but will likely give us more current resources. Go to the left column:
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Subjects focus on what the article is actually about, and thus narrow the focus. Choose the following two subject limiters, one at a time. The screen will refresh each time you click on a box:
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Since our result list is still quite large, we can choose between one of two other possible subjects. In this case, let's choose "sea ice."
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We now have only 523 articles. Note that all our limiters are listed on the left. To turn any one of them off, click the x to the right of it.
