Problem with Series and Groupby
When I do:

In [5]: w=cPickle.load (open('w.pkl'))

In [6]: w.groupby( lambda k: k<=37 ).count()
Out[6]: 
key_0
False    4397
True     16

In [7]: len(w[w <= 37])
Out[7]: 805

When I inspect the data, there are 805 elements that satisfy  w<=37, so the groupby is not counting correctly and reports only 16. 

Am I doing this wrong? 

BTW, I would like to attach the data file to this, but I can't see how.

Thanks!
