[pymvpa] using Balancer()
mih at debian.org
Thu Jul 26 12:51:54 UTC 2012
On Wed, Jul 25, 2012 at 03:11:47PM -0400, Edmund Chong wrote:
> Hi all,
> Currently I have unbalanced samples in each run (unequal number of samples
> per condition).
> If I do leave-one-run-out classification, am I correct to use the following
> partitioner in my classifier to ensure an equal number of samples per
> condition, for each classification fold?
Looks good. If you want to check it yourself, you can also call
.generate() of this chain node with you dataset and print .summary() of
the datasets it returns.
> Also, what happens if in some runs, I have no trials for a certain
> condition? I imagine that on folds where those runs are part of the "test
> dataset", this would be problematic (nothing to test against)? So are
> those fold entirely excluded from the analysis if I use Balancer?
I don't think it would exclude any runs entirely, but you would be
lacking something to test on, indeed.
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