Class MCNullDist
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Class to determine the distribution of a measure under the NULL
distribution (no signal).
No assumptions are made about the shape of the distribution under the null
hypothesis. Instead this distribution is estimated by performing multiple
measurements with permuted label
vectors, hence no or random signal.
The distribution is estimated by calling fit() with an appropriate
DatasetMeasure or TransferError instance and a training and a
validation dataset (in case of a TransferError). For a customizable
amount of cycles the training data labels are permuted and the
corresponding measure computed. In case of a TransferError this is the
error when predicting the correct labels of the validation dataset.
The distribution can be queried using the cdf() method, which can be
configured to report probabilities/frequencies from left
or right
tail,
i.e. fraction of the distribution that is lower or larger than some
critical value.
This class also supports FeaturewiseDatasetMeasure. In that case cdf()
returns an array of featurewise probabilities/frequencies.
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fit(self,
measure,
wdata,
vdata=None)
Fit the distribution by performing multiple cycles which repeatedly
permuted labels in the training dataset. |
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cdf(self,
x)
Returns the frequency/probability of a value x given the estimated
distribution. |
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Inherited from object :
__delattr__ ,
__getattribute__ ,
__hash__ ,
__new__ ,
__reduce__ ,
__reduce_ex__ ,
__repr__ ,
__setattr__ ,
__str__
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__permutations
Number of permutations to compute the estimate the null
distribution.
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Inherited from object :
__class__
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__init__(self,
permutations=1000,
**kwargs)
(Constructor)
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Cheap initialization.
- Overrides:
object.__init__
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Fit the distribution by performing multiple cycles which repeatedly
permuted labels in the training dataset.
- Overrides:
Distribution.fit
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Returns the frequency/probability of a value x given the estimated
distribution. Returned values are determined left or right tailed
depending on the constructor setting.
In case a FeaturewiseDatasetMeasure was used to estimate the
distribution the method returns an array. In that case x can be
a scalar value or an array of a matching shape.
- Overrides:
Distribution.cdf
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