# Boolean operators in search engines

Discussion in 'Computing and ICT' started by sdinnage, Apr 10, 2011.

1. ### sdinnage

I understand the issue, it is difficult to find good examples where using boolean operators makes a clear improvement to results.
With my groups I started with some physical assessment of their own understanding of logical statements AND OR NOT etc. e.g Stand up if you are a girl AND in the back row, stand up if you are in row 1 AND row 2, we found that it was a common misconception that you could easily be in both rows, we finished on a Not statement!
As we had watched the april fools from the BBC about flying penguins in a previous lesson they then used advanced search to show "flying penguins" finds a lot of offical looking websites with the content but "flying penguins" -"April fool" drops nearly all of these out of the results.
Another useful feature is that clicking the cached website in google search results actually highlights the found search terms in yellow (though those cached sites were filtered at school so a screenshot was used).
From our T1 and Inital Levelling tests, advanced search and boolean seem to be some of the weakest areas for KS3. I'd also say the job of teaching accurate use of the web for finding and evaluating information is a major task, but it can be more fun that identifying top level domains, many of which can be registered by anyone with about &pound;7 to spare!

2. ### scaredymare

Thank you both. I like the idea of physical AND NOT OR and will have a go with that followed by advanced search. I'm due be observed by slt in the 2nd lesson of this unit. Might do it then!

3. ### sdinnage

Another idea I took from another ICT trainee was a Guess Who starter.
Up on the screen are a list of names Vs Cartoon characters, a pupil, we call them "google" come up the front and is given a character name in secret. The class can ask questions and only be given TRUE/FALSE answers, when enough information is given they can guess who.
This works quite well as a fun intro and the result should be something like
has got Green eyes AND black hair AND a beard so you can work from that onto searching and specific keywords/terms.
Matt Cutts of Google has a useful video here:
P.S. One class got the name before asking questions, because they could see through my paper, I had another one so we still got a result.
Good Luck

4. ### JaquesJaquesLiverotEstablished commenter

Google used to do OR by default, but now it does AND by default when you enter multiple terms, and I can't really think of a time when I've actually wanted to use OR in a web search. None of the kids (or adults, actually) I come across seem to know about " and -, though, and they're much more useful.
If you're looking at searching and search results, a good example to use is Hayley Wilson - she's yje singer in a band called Paramore, and had a hit last year with a song called Airplanes, which the kids will all know. If you search in Google for Hayley Wilson, however, none of the things on the first page - either links, images or YouTube clips - are her, so you need to add some more terms.
Databases are probably better for demonstrating Boolean logic, and how there is often more than one way to describe the same thing - e.g. if you want to find things that happened on a weekday, you can search for "day = Monday OR day = Tuesday OR day = Wednesday OR day = Thursday OR day = Friday", but it's easier to search for "day <> Saturday AND day <> Sunday".

6. ### anon2246

Hi

I understand how this could potentially be difficult to teach. I've used the boolean circles (you'll find in google images) to accommodate the more visual learners. Also a word of warning is that you may get some bright spark that notices that there are actually two types of OR. The OR discussed is actually what I call the unnatural OR because it also acts as an AND. However the exclusive OR (XOR) means you can either have one or the other, not both.

I'm sure its not strictly required to go that deep for OCR but it can get confusing to explain this to pupils if ever it came up in a class discussion.

Happy teaching!!