Book Image

Python for Finance

By : Yuxing Yan
Book Image

Python for Finance

By: Yuxing Yan

Overview of this book

Table of Contents (20 chapters)
Python for Finance
Credits
About the Author
Acknowledgments
About the Reviewers
www.PacktPub.com
Preface
Index

T-test and F-test


In finance, T-test could be viewed as one of the most used statistical hypothesis tests in which the test statistic follows a student's t distribution if the null hypothesis is supported. We know that the mean for a standard normal distribution is zero. In the following program, we generate 1,000 random numbers from a standard distribution. Then, we conduct two tests: test whether the mean is 0.5, and test whether the mean is zero:

>>>from scipy import stats
>>>np.random.seed(1235)
>>>x = stats.norm.rvs(size=10000)
>>>print("T-value   P-value (two-tail)")
>>>print(stats.ttest_1samp(x,5.0))
>>>print(stats.ttest_1samp(x,0)) 
T-value   P-value (two-tail)
(array(-495.266783341032), 0.0)
(array(-0.26310321925083124), 0.79247644375164772)
>>>

For the first test, in which we test whether the time series has a mean of 0.5, we reject the null hypothesis since the T-value is 495.2 and the P-value is 0. For the second...