def _init_fld2val_stats(self, name, vals):
        """Return statistics on values."""
        vals_stats = stats.describe(vals)
        stddev = math.sqrt(vals_stats[3]) # stats variance
        p25 = np.percentile(vals, 25)
        p50 = np.percentile(vals, 50) # median
        p75 = np.percentile(vals, 75)
        fld2val = {
            'name':name,
            'qty'.format(ITEMS=self.desc):vals_stats[0], # stats nobs
            'range':self._get_str_range(vals_stats),
            '25th percentile':p25,
            'median':p50,
            '75th percentile':p75,
            'mean':vals_stats[2], # stats mean
            'stddev':stddev}
        fmtflds = set(['25th percentile', 'median', '75th percentile', 'mean', 'stddev'])
        mkint = "," in self.fmtstr
        for key, val in fld2val.items():
            if key in fmtflds:
                if mkint:
                    val = int(round(val))
                fld2val[key] = self.fmtstr.format(val)
        return fld2val
Return statistics on values.