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Topic: Sampling From Finite Population with Replacement
Replies: 28   Last Post: Sep 30, 2010 6:30 AM

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 cagdas.ozgenc@gmail.com Posts: 58 Registered: 3/29/06
Re: Sampling From Finite Population with Replacement
Posted: Sep 29, 2010 8:12 AM

On Sep 29, 3:56 pm, "Luis A. Afonso" <lic...@hotmail.com> wrote:
> When a problem is ill  posed it is difficult to get what it is really asked for.
> Suppose I generate data from a NORMAL MODEL N(mu, var). Considering any finite set N of values we know that, generally speaking, the sample mean, m, does not coincide with mu.
> _______  mu = m + bias
> This bias tends to ZERO when N grows ro infinity.
> The same way in what concerns variance and its unbiased estimator, the sample variance, svar, which?s the sum of the squared deviations divided by N-1.
> ________ svar = var + bias´

I don't know what question you answered here but I will disagree with
you here again. What you are describing here is not a bias, it is a
random error. If N is a random sampling from the normal model you
specified, calculated sample mean contains a random error not a bias
because error is just related to samples you selected, not to a