Statistical thinking week 4

mohan palanisamy

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Nov 6, 2020, 12:21:24 PM11/6/20

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Any one know how to derive, please share for the below.

1 point

If the sample covariance between xx and yy is 45, sample variance of xx is 36 and sample variance of yy is 100, then what is the sample correlation coefficient?

0.55

0.65

0.75

0.85

--

Regards

Mohan

Mobile 9663368039

Statistics 1 Support 1

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Nov 6, 2020, 12:41:45 PM11/6/20

to Discussion forum for Statistics for Data Science I, mohan palanisamy

Hello,

If you look at the correlation coefficient formula, it is Covar(x,y)/Sx*Sy So, you need the standard deviation of x and standard deviation of y. Sample standard deviation is equal to the square root of sample variance. Try solving using this.

Thanks & Regards,

Ram,
Course Support Team

mohan palanisamy

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Nov 7, 2020, 1:43:05 AM11/7/20

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Hello sir

Noted product of covariant is 46

And std deviation are 10 and 35 respectively.

Then

45/3600= ans is not matching.

Regards
Mohan

mohan palanisamy

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Nov 7, 2020, 5:17:48 AM11/7/20

to Statistics 1 Support 1, Discussion forum for Statistics for Data Science I

Please clarify till then I will not sleep 😃

Regards
Mohan

statistics-1

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Nov 7, 2020, 5:35:54 AM11/7/20

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Hi,

Divide by the standard deviation of both the variables not by the variance of both the variables.

Thanks

Ankur Upadhyay

Course Support Team

mohan palanisamy

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Nov 7, 2020, 6:05:23 AM11/7/20

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