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  #1  
Old 08-01-2013
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Stats Statistics question

Study is made to analyze the relationship of vitamin B12 and methylmalonyl-COA level. Researchers show that there is an inverse relationship, the correlation coefficient is -0.7 (p<0.05). How much variability in plasma methylmalonyl-COA is explained by B12 intake?

A) >0.95
B) 0.70
C) <0.05
D) 0.49
E) 0.25
F) 99.7
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Old 08-01-2013
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Idea!

D.49
whats the ans?
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Old 08-01-2013
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B as I guess, but really dont know how to calculate variability ???
need to explain , if that is possible
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A) >0.95 because p is <0.05
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Old 08-02-2013
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rg99 got it right

You take the square of correlation coefficient to predict variability
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Old 08-02-2013
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whats the right ans??
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Old 08-02-2013
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A? The study is statistically significant and meaning there is less than 0.05 probability that it was due to chance alone. Reverse this statement: there is >0.95 probability that the variability is explained by the exposure
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Old 08-03-2013
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Guys are you kidding me? Im sayin:

"rg99 got it right"

Which means 0.49 is the snswer
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Old 08-30-2013
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Default ??

Can somebody explain the answer to this question! Please.
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Old 08-30-2013
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Quote:
Originally Posted by usmlestep1taker View Post
Can somebody explain the answer to this question! Please.
To calculate the variability Doc is explaning that you just take it to the SQUARE 7x7 = .49

nice.
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