sigma^2

  1. T

    Parametrising LogNormal distribution knowing only sample mean, and 90th percentile

    I'm a little stuck, and hope someone will be able to explain this to me. I have sample mean, and value of the 90th percentile of the sample. If distribution is assumed to be LogNormal, is there a way of estimating parameters of mu and sigma of that LogNormal distribution? I'm trying to...
  2. R

    I need help

    I need help I have this homework that I cant solve it Show that s^2=(1|n-2)∑(y-y^) is unbiased estimator for sigma^2 in linear regression model can you help me??????
  3. B

    E[MSE] simple linear regression

    Hi All- I am trying to figure out how to prove that MSE = SSE/n-2 is an unbiased estimator of sigma^2 in simple linear regression. I have that (1/(n-2))E{SUM[Yi^2-2Yib1Xi-2boYi+bo^2+b1^2Xi^2]} Are bo and b1 random variables? Am I going about this the right way? Thanks!