OLS regression for bootstrapped data

Hi, I bootstrapped some data 1000 times and now I want to regress each one of the columns of that bootstrapped data (A) on two vectors. This is: Y= each column in A; X=two vectors, but the "regress" command is not working. Any suggestion? All the data has the same number of rows. Thanks!

[jgg]

Shouldn't you be repeating the regression command 1000 times? Something like:

 for i = 1:1000
   Y = A(:,i);
   b(i) = regress(Y,X);

 end

then do analysis on the 1000 b values reported?

[Alma Bezares]

Yes, that's exactly what I want to do. Do the regression 1000 times. The problem is that if I use the code that you suggested, it only does the regression on column 1000 and not on the rest of them. If I set Y=(1:i), the command won't work as I'm dealing with a matrix again.

Answer 1

[jgg]

To answer your question based on my comment. The command Y = A(:,i) selects the i-th column from the A matrix, so this will give you your 1000 results. For instance,

 X = randn(5000,2); %fake data; use real data
 A = randn(5000,1000); %fake data;

 betas = zeros(1000,2);
 for i = 1:1000
  Y = A(:,i);
  betas(i,:) = regress(Y,X);
 end

Your estimates are stored in the betas matrix so you can average or consider standard deviation etc.

[Alma Bezares]

That seems to work. Thanks a lot!!