Well, here is a good source--wikipedia. 
 
http://en.wikipedia.org/wiki/Bootstrapping_(statistics)


________________________________

        From: Áõ½Ü [mailto:[EMAIL PROTECTED] 
        Sent: Monday, July 21, 2008 3:56 PM
        To: Doran, Harold
        Cc: Michal Figurski; Frank E Harrell Jr; r-help@r-project.org
        Subject: Re: [R] Coefficients of Logistic Regression from bootstrap - 
how to get them?
        
        
        Hi Doran,
         
        Maybe I am wrong, but I think bootstrap is a general resampling method 
which can be used for different purposes...Usually it works well when you do 
not have a presentative sample set (maybe with limited number of samples). 
Therefore, I am positive with Michal...
         
        P.S., overfitting, in my opinion, is used to depict when you got a 
model which is quite specific for the training dataset but cannot be 
generalized with new samples......
         
        Thanks,
         
        --Jerry
        
        2008/7/21 Doran, Harold <[EMAIL PROTECTED]>:
        

                > I used bootstrap to virtually increase the size of my
                > dataset, it should result in estimates more close to that
                > from the population - isn't it the purpose of bootstrap?
                
                
                No, not really. The bootstrap is a resampling method for 
variance
                estimation. It is often used when there is not an easy way, or 
a closed
                form expression, for estimating the sampling variance of a 
statistic.
                

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