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chendawg17
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Double set matrix

by chendawg17 Mon Jul 12, 2010 8:09 pm

I was wondering if anyone would be able to help me to understand how to set up the matrices better. I understand why the events need to be mutually exclusive, but I fail to see in the examples how one set up would be incorrect over the other. Thanks in advance!
dinesh19aug
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Re: Double set matrix

by dinesh19aug Wed Jul 14, 2010 5:06 pm

chendawg17 Wrote:I was wondering if anyone would be able to help me to understand how to set up the matrices better. I understand why the events need to be mutually exclusive, but I fail to see in the examples how one set up would be incorrect over the other. Thanks in advance!


It would help if you could pick the example from guide and post.
chusbaez
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Re: Double set matrix

by chusbaez Wed Jul 14, 2010 10:54 pm

If you understand why the events must be mutually exclusive then you could never be wrong, because when you design the matrix, each column and row will amount to a sensible TOTAL.

example,
15% of all the guys at work sat for the GMAT, while 80% of the girls did not sit for the GMAT.
there are 200 people at work, 50% are guys.

......SAT GMAT......DID NOT.....TOTAL
GUYS ......15 ............. 85 ..........100
GIRLS ......20............. 80 .......... 100

TOTAL ......35............165 ........... 200

that is, TOTAL GUYS: 100, TOTAL GIRLS:100
TOTAL people who sat GMAT: 35, TOTAL who did not: 165

try to put "guys" next to "SAT GMAT" in a row, does it make sense?
tim
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Re: Double set matrix

by tim Sat Sep 04, 2010 3:01 pm

i agree with dinesh; if your row or column headings are mutually exclusive, you're fine..
Tim Sanders
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