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标题: Chevychev's Inequality [打印本页]

作者: franzino    时间: 2011-7-13 16:29     标题: Chevychev's Inequality

Does anyone know why do we have k>1 in the formula of Chevychev's inequality. I know this is for any distribution, not limited to normal distribution. Sign of K should not make any difference as we have K^2 in the formula. I just want to make sure I am not missing anything here.
作者: Wasteoftime    时间: 2011-7-13 16:29

THe formula is 1- 1/(k^2).

If k=1, then the result is 0 -> doesnot make sense
作者: dcfox83    时间: 2011-7-13 16:29

also if k is between 0 and 1, when you square it, it gets smaller. Whereas a number above 1 obviously gets bigger.....
作者: rkapoor    时间: 2011-7-13 16:29

I know but how about K<0. Why is that not included? Any specific reason or just to avoid these limits stated by you guys..
作者: hariRaj    时间: 2011-7-13 16:29

It's ok to have K <0 bcos we square K in the formula. Positive or negative both yield the same result.
作者: eagles_dare13    时间: 2011-7-13 16:29

K is the number of stds away from the mean right? so it cant be negitive because you would use absolute value?




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