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From: Peter Perkins <Peter.PerkinsRemoveThis@mathworks.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: bootstrap
Date: Thu, 03 Apr 2008 11:35:32 -0400
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Peter Perkins wrote:
> Corinne wrote:
>> Thanks Peter, I'll try to explain it a bit better. So essentially what 
>> I would like to do is re-sample the data
>> 100 times, and take the average rms value at each point. So
>> I have a 56x13 matrix of gridded and interpolated ocean
>> tracer data. I would like to get back a 56x13 matrix of the
>> average rms values for each point in the matrix.  From this,
>> I wnat to plot the average rms data to look at where the
>> highest/lowest areas of errors are and generate a total
>> error on my data.
> 
> Corinne, in order to use the bootstrap properly, you need to define how 
> your bootstrap samples will be drawn from your original data, and that 
> requires you to think about how your data were originally sampled, 
> whether they are independent and identically distributed or not, and if 
> not, what component of your data is independent and identically 
> distributed.

To me, it sounds like your matrix of data represents a spatial 
configuration, and somehow your bootstrap samples would have to preserve 
that, and so perhaps you need a stratified bootstrap.  But it sunds like 
you have only one sample in each stratum, which means you can usefully 
bootstrap.