案例：
tt = (sm-m)/np.sqrt(sv/float(n)) # t-statistic for mean pval = stats.t.sf(np.abs(tt), n-1)*2 # two-sided pvalue = Prob(abs(t)>tt) print 't-statistic = %6.3f pvalue = %6.4f' % (tt, pval) t-statistic = 0.391 pvalue = 0.6955tt = (sm-m)/np.sqrt(sv/float(n)) # t-sta
