我想使用python 3.7进行t检验。我有以下数据：
date,return
2014-11-30,0.011635519414351009
2014-12-31,0.021954092308170955
2015-01-31,0.04088726605224263
2015-02-28,-0.0025112428290965105
2015-03-31,0.01725861669076579
2015-04-30,0.04169672034614155
2015-05-31,0.033973104078552634
2015-06-30,0.011808567427224085
2015-07-31,-0.034296712711723694
2015-08-31,-0.018000336527001545
我创建了以下示例：
import pandas as pd
import numpy as np
import scipy.stats as stats
def analyze_returns(net_returns):
"""
Parameters
----------
net_returns : Pandas Series
A Pandas Series for each date
Returns
-------
t_value
t-statistic from t-test
p_value
Corresponding p-value
"""
m = np.mean(net_returns)
# null_hypothesis = 0.0
t_value, p_value = stats.ttest_1samp(net_returns, m) / 2
return t_value, p_value
def test_run(filename='./data/net_returns.csv'):
"""Test run analyze_returns() with net strategy returns from a file."""
net_returns = pd.Series.from_csv(filename, header=0)
t, p = analyze_returns(net_returns)
print("t-statistic: {:.3f}\np-value: {:.6f}".format(t, p))
if __name__ == '__main__':
test_run()
运行stats.ttest_1samp(net_returns, m) / 2时，出现以下错误：
<ipython-input-3-12a76e5e6042> in analyze_returns(net_returns)
26 # null_hypothesis = 0.0
27
---> 28 t_value, p_value = stats.ttest_1samp(net_returns, m) / 2
任何暗示我做错了吗？