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  #1  
Old 06-01-2011
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Stats Biostatistics #1 - triglyceride levels and degree of atherosclerosis

An investigator determines the correlation coefficient between triglyceride levels and degree of atherosclerosis in sampled blood vessels to be +1.67. On the basis of this you would conclude that:

A. Triglyceride level is a good predictor of atherosclerosis
B. Triglyceride level is not a good predictor of atherosclerosis
C. High triglyceride levels cause atherosclerosis
D. Atherosclerosis causes high triglyceride levels
E. The investigator has incorrectly determined the correlation coefficient.

Last edited by bebix; 06-01-2011 at 06:42 PM.
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  #2  
Old 06-01-2011
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positive relation as it is + and >1..
So i would go with A
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Old 06-01-2011
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Quote:
Originally Posted by struggle View Post
positive relation as it is + and >1..
So i would go with A

i think A too but y not C ??
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  #4  
Old 06-01-2011
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Because its not the only factor causing atherosclerosis..
It shows a correlation (risk factor) but not a 100% causal factor..
I guess so..i dont know if i am wrong
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Old 06-01-2011
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Maximum for correlation coefficien is +1. so I think E is correct!
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Old 06-01-2011
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E absuloutely ..
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Old 06-01-2011
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I think its E
b/c its more than 1
and the range usually b/t -1 to 1
and about choice C , it's absolutely wrong b/c the correlation coefficient is not a causal relation whenever you see causal relationship don't pick it in the exam
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Old 06-02-2011
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I think is E)
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Old 06-02-2011
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Correct Answer correct answer

The correct answer is E)

The correlation coefficient (r) is an index of the extent to which two variable are linear associated. It can take the values BETWEEN +1.0 and -1.0, depending on the strenght of the LINEAR association and whether a positive change in x produces a positive or negative change in y. An r = 0 indicates the two variables are not linearly related.

Biostatistics #1 - triglyceride levels and degree of atherosclerosis-corr.jpg
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Biostatistics-Epidemiology, Figures-, Step-1-Questions

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