conditional reasoning question Forum

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hutchesonian

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conditional reasoning question

Post by hutchesonian » Tue Aug 10, 2010 2:20 pm

(from Powerscore's Grouping Setup Practice Drill 3)

The game scenario:
1) 2 groups
2) all variables are assigned to a group, no variable is assigned to more than one group

One of the rules has the form: A is assigned to a group only if B is assigned to the same group. Powerscore diagrams this as A --> B. However, given the above scenario, would it be wrong to simply diagram it as [AB]? That is, A and B must be in the same group?

Thanks!

pattymac

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Re: conditional reasoning question

Post by pattymac » Tue Aug 10, 2010 2:44 pm

Nope, you're a step ahead of the game pal. This can be cofirmed via the contrapositve which would say if it doesn't have B, it can't have A....and since there are only two groups, you can figure out where theyre going.

A1 ---> B1

NotB1 ----> NotA1
(B2) (A2)

obviously your method of reasoning is much quicker, especially given the time constraints...just be careful!

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northwood

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Re: conditional reasoning question

Post by northwood » Tue Aug 10, 2010 4:02 pm

the block would work in this case, because all pieces have to be used, and nothing can be left out. IF the game said that things could be left out, then automatically making a conditional a block clue, may hurt you. Especially if you would be working with anti block clues.

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