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mvpa.clfs.stats.FixedNullDist

class mvpa.clfs.stats.FixedNullDist(dist, **kwargs)

Proxy/Adaptor class for SciPy distributions.

All distributions from SciPy’s ‘stats’ module can be used with this class.

Examples

>>> import numpy as np
>>> from scipy import stats
>>> from mvpa.clfs.stats import FixedNullDist
>>>
>>> dist = FixedNullDist(stats.norm(loc=2, scale=4), tail='left')
>>> dist.p(2)
0.5
>>>
>>> dist.cdf(np.arange(5))
array([ 0.30853754,  0.40129367,  0.5       ,  0.59870633,  0.69146246])
>>>
>>> dist = FixedNullDist(stats.norm(loc=2, scale=4), tail='right')
>>> dist.p(np.arange(5))
array([ 0.69146246,  0.59870633,  0.5       ,  0.40129367,  0.30853754])

Parameters :

dist : distribution object

This can be any object the has a cdf() method to report the cumulative distribition function values.

enable_ca : None or list of str

Names of the conditional attributes which should be enabled in addition to the default ones

disable_ca : None or list of str

Names of the conditional attributes which should be disabled

tail : {‘left’, ‘right’, ‘any’, ‘both’}

Which tail of the distribution to report. For ‘any’ and ‘both’ it chooses the tail it belongs to based on the comparison to p=0.5. In the case of ‘any’ significance is taken like in a one-tailed test.

descr : str

Description of the instance

cdf(x)

Return value of the cumulative distribution function at x.

fit(measure, ds)

Does nothing since the distribution is already fixed.