Help on a Chi-square problem plz

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xcuteJinax3
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Help on a Chi-square problem plz

Post by xcuteJinax3 » Sun Mar 05, 2006 3:23 am

On this problem ...

Genetically pure white dogs, when testcrossed to brown dogs, produce an all white F1. Data on 190 F2 progeny: 138 white, 41 black, 13 brown. These coat colors are postulated to be under the genetic control of two loci exhibiting dominance with a 12:3:1 expected ratio. Test this hypotheiss by chi-square.


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I know you use the chi square formula but I seriously have no idea how to solve this. Please help! THANK YOU!!

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MrMistery
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Post by MrMistery » Sun Mar 05, 2006 7:37 pm

What the heck is a chi square? is it like a punnet square?
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canalon
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Post by canalon » Mon Mar 06, 2006 4:13 pm

Chi square is a statistical test designed to see if a distribution of characters is random or link to some characters. As for how to do it, many software can do that for you (MS excel for example), but you will find on the net plenty of good explanations and examples.
See here for some examples. The first 2 are correct and interesting.
Patrick

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sdekivit
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Post by sdekivit » Tue Mar 07, 2006 9:10 am

the chi-square test is used to test statistically wether there is a relation between two variables or not.

xcuteJinax3
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Post by xcuteJinax3 » Tue Mar 07, 2006 3:05 pm

Thank you~~I understand now

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