# pandas.Series.sem¶

Return unbiased standard error of the mean over requested axis.

Normalized by N-1 by default. This can be changed using the ddof argument

- param axis
{index (0)}

- param skipna
- bool, default True
Exclude NA/null values. If an entire row/column is NA, the result will be NA

- param level
- int or level name, default None
If the axis is a MultiIndex (hierarchical), count along a particular level, collapsing into a scalar

- param ddof
- int, default 1
Delta Degrees of Freedom. The divisor used in calculations is N - ddof, where N represents the number of elements.

- param numeric_only
- bool, default None
Include only float, int, boolean columns. If None, will attempt to use everything, then use only numeric data. Not implemented for Series.

- return
scalar or Series (if level specified)

Warning

This feature is currently unsupported by Intel Scalable Dataframe Compiler