@Substitution(name='groupby')
    @Appender(_doc_template)
    def sem(self, ddof=1):

        return self.std(ddof=ddof) / np.sqrt(self.count())
Returns the z-score of a given input score, given thearray from which
dataset/ETHPy150Open pydata/pandas/pandas/core/groupby.py/GroupBy.sem--crossover with--dataset/ETHPy150Open radlab/sparrow/src/main/python/third_party/stats.py/az