pandas.stats.moments.expanding_var

pandas.stats.moments.expanding_var(arg, min_periods=1, freq=None, time_rule=None, **kwargs)

Unbiased expanding variance

Parameters :

arg : Series, DataFrame

min_periods : int

Minimum number of observations in window required to have a value

freq : None or string alias / date offset object, default=None

Frequency to conform to before computing statistic

Returns :

y : type of input argument