Expanding.kurt(self, **kwargs)
[source]
Calculate unbiased expanding kurtosis.
This function uses Fisher’s definition of kurtosis without bias.
Parameters: |
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Returns: |
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See also
Series.expanding
DataFrame.expanding
Series.kurt
DataFrame.kurt
scipy.stats.skew
scipy.stats.kurtosis
A minimum of 4 periods is required for the expanding calculation.
The example below will show an expanding calculation with a window size of four matching the equivalent function call using scipy.stats
.
>>> arr = [1, 2, 3, 4, 999] >>> import scipy.stats >>> fmt = "{0:.6f}" # limit the printed precision to 6 digits >>> print(fmt.format(scipy.stats.kurtosis(arr[:-1], bias=False))) -1.200000 >>> print(fmt.format(scipy.stats.kurtosis(arr, bias=False))) 4.999874 >>> s = pd.Series(arr) >>> s.expanding(4).kurt() 0 NaN 1 NaN 2 NaN 3 -1.200000 4 4.999874 dtype: float64
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Licensed under the 3-clause BSD License.
https://pandas.pydata.org/pandas-docs/version/0.25.0/reference/api/pandas.core.window.Expanding.kurt.html