Neural Networks - Simple question ?

What is the difference between 'dividerand' and 'divideint' ??

[mangood UK]

i am with you

Answer 1

[Greg Heath]

1.Read the command line documentation:

    help dividerand
    doc dividerand
    type dividerand     % If you have permission

 and
     help divideint
     doc divideint
    type divideint    % If you have permission

My naive interpretation:

dividerand: randomly rearranges the integers 1:N ( e.g., with randperm) and with the default ratios 0.7/0.15/0.15, assigns the last Ntst = round(0.15*N) to the test set, the middle Nval = round(0.15*N) to the validation set and the first Ntrn = N - Nval - Ntst to the training set.

Example: choose a value for N and numtrials

 N = 30
 numtrials = 10
 rng(0)     % Initialize the RNG so that the example can be duplicated

 for n =1:numtrials
    [trnind,valind,tstind] = dividerand(N,0.7,0.15,0.15) % no semicolon
 end

divideint: assigns members of the three sets to be as interleaved as possible. For example, if N = 30 then Nval = Ntst = round(0.15*30) = 5 and Ntrn = 20. I don't know the algorithm used by MATLAB (you can check type divideint) but, you could choose the spacing of valind and tstind to be uniform (e.g., = 6), and starting with a number in 1:6.

Hope this helps.

Thank you for formally accepting my answer

Greg

[Dink]

Thanks very much Greg!