Mathematics Stack Exchange
Mathematics Stack Exchange

Questions tagged [variance]

For questions regarding the variance of a random variable in probability, as well as the variance of a list or data in statistics.

In probability and statistics, variance is a measure of spread among the possible values of a random variable or a list of values.

More information can be found here.

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comparing the variance of estimators

when we know that both estimators are unbiased, we prefer the one with a smaller variance. so considering that we want to estimate the population mean using 5 data points, we consider the 2 estimators below: a. Mu1 = (x1+x2+x3+x4+x5)/5 b. Mu2 =…
darrenbarren
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Help find mean and variance please

I have beeen asked to find the pdf of Y for this function. I get y(lamda)^(2)exp{((lamda x Y)^2)/2)}. I am having trouble finding the mean and variance. Can someone help? Thank you. Y =P((2X/λ)^0.5), where X ∼ Exp(λ)
Expectation mean first moment
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