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zoeyfyi / StatsNotes

Notes for SS1 - SS6
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Critical values for correlation coefficeients #71

Closed zoeyfyi closed 7 years ago

zoeyfyi commented 7 years ago

@tpb1908 have you found a way to get these on the calculator. So far I haven't needed the tables but I don't think they are on their.

tpb1908 commented 7 years ago

I saw Screenshot_20170129-133925.png this which might be how to do it, but I didn't see a built in function.

tpb1908 commented 7 years ago

Take a look at the bottom formula here

tpb1908 commented 7 years ago

I found out how to do it.

Use the student_cdf function with the following arguments

n-2 , r/sqrt((1-r^2)/(n-2)), 1e99 (large value)

The values match up with this calculator

zoeyfyi commented 7 years ago

That cant be it since the table looks up the critical value of r, you only have the significance level and sample size: image

zoeyfyi commented 7 years ago

student_cdf(n-2 , r/sqrt((1-r^2)/(n-2)), 1e99 (large value)) gives you the Pearson correlation coefficient, which I havnt done yet.

tpb1908 commented 7 years ago

Sorry, the only other formulae I have found are here and they are all approximations for n > 30.

ctrl +f in the manual for spearman, correlation, rank etc doesn't find anything.

Might have to resort to using the tables.

zoeyfyi commented 7 years ago

Thats a shame, not to bad though.

I just ordered these books:

They where pretty cheap used so I thought, why not. You welcome to borrow any when they arrive.