pandas.core.window.expanding.Expanding.sem

Expanding.sem(ddof=1, numeric_only=False)[source]

Calculate the expanding standard error of mean.

Parameters:

ddof:int, default 1

Delta Degrees of Freedom. The divisor used in calculations is N - ddof, where N represents the number of elements.

numeric_only:bool, default False

Include only float, int, boolean columns.

Added in version 1.5.0.

Returns:

Series or DataFrame

Return type is the same as the original object with np.float64 dtype.

See also

pandas.Series.expanding

Calling expanding with Series data.

pandas.DataFrame.expanding

Calling expanding with DataFrames.

pandas.Series.sem

Aggregating sem for Series.

pandas.DataFrame.sem

Aggregating sem for DataFrame.

Notes

A minimum of one period is required for the calculation.

Examples

>>> s = pd.Series([0, 1, 2, 3])

>>> s.expanding().sem()
0         NaN
1    0.707107
2    0.707107
3    0.745356
dtype: float64