Presentation is loading. Please wait.

Presentation is loading. Please wait.

Boolean Search Techniques for the Web OR How Do Smart GRRLz Search The Web?

Similar presentations


Presentation on theme: "Boolean Search Techniques for the Web OR How Do Smart GRRLz Search The Web?"— Presentation transcript:

1 Boolean Search Techniques for the Web OR How Do Smart GRRLz Search The Web?

2 Smart GRRLz...... search the web and databases by using Boolean logic. Boolean logic is named for George Boole, who was a famed English mathematician. Using Boolean logic makes your searches more effective and accurate.

3 Boolean logic offers three search options: AND NOT OR I know they don’t sounds like much, but you have already used an “AND” search and you probably don’t know it!

4 AND is the most frequently used Boolean search A search using AND will look like this: poverty crime You do not have to type the word “AND.” Just put two or more words together in a row. The computer assumes that the blank space between the two words equals “AND.”

5 This sequence tells the computer, “I want all the articles in this database that include both of these words somewhere in them.” The gray area on the right indicates the items that include both the word “poverty” and the word “crime.”

6 The AND operator works like a funnel-shaped filter The more search terms you use (with spaces in between them) the fewer and fewer results will come back from your search. These fewer results will be specifically focused on your particular area of research.

7

8

9

10

11

12

13 I’m going to demonstrate how this works in Google! I’m going to show you how the Boolean operator AND works in Google ! Google makes it easy for you to see what I’m talking about...

14 We will use the AND search poverty crime Into Google

15

16

17

18

19

20

21

22 NOT! The second most popular Boolean operator is NOT. NOT works like AND in that the more search terms you use with NOT, the fewer and more focused your results will be.

23 If you did a search for articles about cats, but you did not want to get any articles about dogs in your search results, you would enter: Cats –dogs The grey area on the right represents the search results that include only cats, not dogs.

24 I demonstrate the NOT operator in eBay. If you learn how to use it there, you can use it anywhere. In most search engines, the NOT operator is represented by a minus sign in front of the word you do not want in your search. For example: Clinton -Whitewater

25

26

27 What if you wanted information about floods caused by rain? You don’t want anything about New Orleans and you are not interested in hurricanes. What would your search string look like?

28 It might look like these... Flood rain –hurricane –”new orleans” –levee Or Flood rain –levee –levees –floodwall –surge Or Flood rain –katrina –rita –overtopped

29 Notice that there is NO space...... between the minus sign and the following word! Flood rain –hurricane –”new orleans” –levee Or Flood rain –levee –levees –floodwall –surge Or Flood rain –katrina –rita –overtopped

30 OR The third and last Boolean operator is OR. OR is less frequently used, because it does the opposite of what AND and NOT do. That is, it explodes your search results. It does not give you fewer. OR gives you MORE search results.

31 If you enter a search like this one... college OR university OR campus Your search results will include every article with the word “college,” every article with the word “university,” and every article with the word “campus.” It doesn’t matter if they are all in the same article or not.

32 The OR operator is used when the thing you are looking for has more than one legitimate name. For example: “Standards of Learning” is also called “SOL.” When to Use the OR Operator

33 The other time to use the OR search...... is when you want to find every article on your subject, even if the name of the subject is spelled wrong in the article. In the next example we will search for three variations on Edgar Allan Poe’s name. Sometimes he was called E.A. Poe instead of Edgar Allan. And what if you did not know how he spelled “Allan?”

34

35

36 “Phrase Searches” Some of you may have noticed that in the eBay search we did earlier I put quotation marks around the words “cell phone.” I did this so that the two words would stay together in my search results in that order.

37 If you search for: Cell phone Without quotes around the two words, what kind of search is that? That kind of search might bring back a page that says “James was on the phone when police arrested the members of a terrorist cell.” And that would not be what you wanted...

38 To prevent this kind of confusion...... we place quotation marks around any two or more words that we want the computer to find in exact order. It even works with names. For example: “e.a. poe” “edgar allen poe” “edgar allan poe”

39 It’s good to use phrase searches when you are looking for the name of an...... organization: “national rifle association” “win with women” “american association of retired persons”

40 You can even combine Phrase Searches with AND or NOT searches... to get very specific results: “while I pondered weak” poem “sugar magnolia blossoms” lyrics “thank god almighty I’m free” speech

41 Do you...... Think you can do Boolean searches on your own now?


Download ppt "Boolean Search Techniques for the Web OR How Do Smart GRRLz Search The Web?"

Similar presentations


Ads by Google