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Testing to decide difference between variability

C

Chandrima

Member
How to do part(ii) ? In the solution, some delta concept is being used. What is this delta? How are they calculating this delta?? Please help.
 

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This Delta is the variance of the sample data.
The test statistic used while checking for equality of variances is variance of x/variance of y, where x and y are the sample data
 
Ok. But I am getting different variances for dataset A and dataset B using formula of variance
s^2 = (1/n-1)*(summation of x^2 - n*x-bar^2)
Using this, s(A)^2 is coming 3.69643 and s(B)^2 is coming 2.4107. Right???
 
Sorry, now I got it. Now I just fed the data sets in calculator and found sx and sy, and squared them. Thanks!
 
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