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Old October 28th, 2009, 09:22 AM
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Default Exponential Distribution Question

Let X be teh mean of a random sample from the exponential distribution Exp(\theta)

Show that X is an unbiased point estimater of \theta

Which PDF of the exponential function do I use?

or
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Old October 28th, 2009, 10:02 AM
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The sample mean is an unbiased estimator for the true mean. For which of those distributional forms is the defining parameter the mean? That should give you the answer.
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Old October 28th, 2009, 11:19 AM
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IF X_1,X_2,... are iid then

E(\bar X)=\mu which is \theta in this case

or \lambda or \beta
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Old October 28th, 2009, 11:31 AM
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Quote:
Originally Posted by matheagle View Post
IF X_1,X_2,... are iid then

E(\bar X)=\mu which is \theta in this case

or \lambda or \beta
That part I got I wasnt sure which one of the PDF I needed to use, since the one with lambda's expectation is 1/lambda (according to wikipedia)
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Old October 28th, 2009, 12:03 PM
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They are the same, \lambda=1/\beta use whatever your book is using.
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Old October 28th, 2009, 12:04 PM
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That clears that up. Thanks.
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