These both sound to me as if multi-level models would be appropriate to
handle the type of data to which you are referring.
Look at this site for some basic info on multi-level models (MLM):
http://www.ioe.ac.uk/multilevel/
Interested in learning more... then dowload this classic text on MLM for
free:
http://www.arnoldpublishers.com/support/goldstein.htm
Finally, If you decide this method is what you are looking for, then have a
look at the following text that describes Linear MLM or as they call it
Hierarchichal Linear Models (HLM)--the multilevel equivalent of linear
regression:
Bryk,A.S., and Raudenbush,S.W. (1992). Hierarchical Linear Models. Newbury
Park, Sage.
-----Original Message-----
From: Rich Strauss [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, February 28, 2001 2:40 PM
To: [EMAIL PROTECTED]
Subject: Re: Regression with repeated measures
I don't have an answer, but I'm very glad this question was asked because
I'm having a similar problem. I have 14 grids, values from which are to be
used as the dependent variable in a regression. Each 6x6 grid consists of
36 observation points. Their are some fairly strong spatial correlations
among the values at each grid, so I certainly can't treat them as if they
were independent, yet reducing each grid to a single mean value (the other
extreme) seems like a foolish waste of power. I'm trying to figure out how
to use all of the observations, but also use the estimated spatial
autocorrelations to weight them in the regression. (The design was
originally created to answer a very different question, which is how I got
into this mess.)
I hope that there's a single answer to both of our questions.
Rich Strauss
At 10:54 AM 2/28/01 -0600, Michael M. Granaas wrote:
>
>I have a student coming in later to talk about a regression problem.
>Based on what he's told me so far he is going to be using predicting
>inter-response intervals to predict inter-stimulus intervals (or vice
>versa).
>
>What bothers me is that he will be collecting data from multiple trials
>for each subject and then treating the trials as independent replicates.
>That is, assuming 10 tials/S and 10 S he will act as if he has 100
>independent data points for calculating a bivariate regression.
>
>Obviously these are not independent data points.
>
>Is the non-independence likely to be severe enough to warrant concern?
>
>If yes, is there some method that will allow him to get the prediction
>equation he wants?
>
>Thanks
>
>Michael
========================
Dr Richard E Strauss
Biological Sciences
Texas Tech University
Lubbock TX 79409-3131
Email: [EMAIL PROTECTED] (formerly [EMAIL PROTECTED])
Phone: 806-742-2719
Fax: 806-742-2963
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