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Mar
30
comment Meaning of correlation
Maybe you'll understand and enjoy Correlations Genuine and Spurious in Pearson and Yule maybe not.
Mar
30
comment Meaning of correlation
And that is devoid of meaning for the real world as to whether you can deduce from a high $\hat{\rho}$ that $y = a + bx + \mathrm{noise}$ based on observations on $x$ and $y$.
Mar
30
comment Meaning of correlation
No ... whether the variables are linearly related (except in the case of perfect correlation) cannot be determined via the correlation coefficient. Being close to a straight and being linearly related are different things.
Mar
30
comment Meaning of correlation
Sure. But if you have $r_{xy} = 0.9$ and $r_{wz} = 0.85$ it doesn't automatically follow that there is a "more linear" relationship between between $x$ and $y$ than there is between $w$ and $z$. It just means $(x,y)$ pairs are closer to a line than are $(w,z)$ pairs. See also en.wikipedia.org/wiki/Correlation_and_dependence#/media/…
Mar
30
answered Meaning of correlation
May
14
revised Why is cos(90)=0.4 in WebGL?
Fix spelling of summarize
May
14
suggested approved edit on Why is cos(90)=0.4 in WebGL?
Feb
11
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Oct
19
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Aug
9
comment How to determine if coin comes up heads more often than tails?
The standard deviation of the sampling distribution of counts for sample size 24000 is $\sqrt{24000 x 0.5 x 0.5}$ That is, about 48% of all samples of size 24000 will yield a count of heads between 11950 and 12950. And, 95% of sample proportions will be between .494 and .506. That's due to the CLT.
Aug
8
revised How to determine if coin comes up heads more often than tails?
added 251 characters in body
Aug
8
comment How to determine if coin comes up heads more often than tails?
@Pete: Why would 12,012 heads after 24,000 flips be fishy? I just asked my computer to flip the coins and got 11,996. How else would the LLN work?
Aug
8
comment How to determine if coin comes up heads more often than tails?
@Pete I did not suggest that the set of people who flipped a coin many times to be limited to the three I mentioned. Those are the ones that I know are documented. However, I hope you would agree that FEW would be the appropriate adjective to describe the number of people who have tossed the same coin repeatedly that many times. I used to assign a homework where students were required to toss a coin 20-30 times. I know most of them could not be bothered with that.
Aug
8
revised How to determine if coin comes up heads more often than tails?
edited body
Aug
8
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Aug
8
revised How to determine if coin comes up heads more often than tails?
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Aug
8
answered How to determine if coin comes up heads more often than tails?
Aug
8
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