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To search for resources on hot air balloons, do you start with a directory such as Yahoo or a search engine such as Altavista? In order to choose a starting point, it is good to imagine what kinds of resources might be found on the web. For hot air balloons, there could be, and probably are, resources for balloon enthusiasts, history buffs, tourists who want to take a balloon ride, as well as resources for teachers. There could be a great many pages and your task will be to locate only the ones that are useful to you. Yahoo will list the most stable pages and those which will be of interest to the greatest number of people. If you start there, you will pick up business -oriented pages such as:
Still, these are interesting sites that give your students a wider context for their studies. Yahoo also lists hobbiest interests that are closer to those of the classroom:
TIP: When you search Yahoo, which is a hierarchical directory,you are looking for subject headings which will yield pages that interest you. If you find a good heading, bookmark it and return directly to it in the future to see if new pages have been posted. TIP: When Yahoo runs out of its own pages, it automatically runs the search in Altavista, using the search stragegy that you provided. So by running the search in Yahoo first, you are covering both bases. You know you have left Yahoo pages when you see the link: Go To Web Page Matches. |
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In constructing the search statement, one important decision to make is whether you want to search using separate words which can be combined in different ways or as a phrase. In many systems, putting words in quotes means that they will be searched as a phrase. In Yahoo if you search on hot air balloons (without quotes), the database will assume you want resources which include the words hot and air and balloons, no matter which order they appear in on the page. While this will pick up the phrase hot air balloons, it will also pick up such pages as:
So, in Yahoo, this is a good stragtegy. But a better one would be: hot air balloon (no quotes, singular). By making the search stragegy singular, you more easily pick up pages like:
which may have been missed if the search statement was plural. Balloon in the singular could also, in some systems, pick up ballooning.
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If we had used the same search strategy in Altavista, this would have been the result: hot air balloons had 6,144,394 hits hot air balloon had 11,558,886 hits "hot air balloon" had 17,988 hits "hot air balloons" had 7,735 hits Why the difference?The Altavista search engine looks at over 200 Gigabytes of data, far more than Yahoo, and your search strategy must be aware of this. Because Altavista looks at pages and the pages linked to pages, it finds more duplicates than Yahoo does. It also will include pages that have only two or only one of the words you present it with, when they are not in quotes or you do not insist that all words appear, by putting a plus sign in front of them like this: +hot +air +balloons. When a lot of pages are on the web, you may not notice this at first, because Altavista ranks the pages, choosing what it feels are the best 200 pages. This ranking will present you with pages with all three words before the pages with just one or two. Altavista also does not have automatic truncation, so that balloon does not pick up ballooning. You have to specify that you want truncation by placing a wildcard character * at the end of a word or word root. "hot air balloon*" had 28,409 hits. Because of this, you will need to modify your search in Altavista, so you will find the pages of most interest to you.
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Try these and other strategies in Yahoo,
Altavista and other search engines and let us know how you
do!
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8/17/98