October 2021
Intermediate to advanced
289 pages
8h 31m
Chinese
Content preview from 数据科学中的实用统计学(第2版)
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
92
｜
第
3
章
在
Python
中，可以使用函数
scipy.stats.ttest_ind
：
res = stats.ttest_ind(session_times[session_times.Page == 'Page A'].Time,
session_times[session_times.Page == 'Page B'].Time,
equal_var=False)
print(f'p-value for single sided test: {res.pvalue / 2:.4f}')
备择假设是页面
A
的会话时间均值小于页面
B
。
p
值是
0.1408
，非常接近于置换检验中的
p
值
0.121
和
0.126
（参见
3.3.2
节
）。
在重抽样模式下，我们可以静心设计解决方案，用来反映观测数据和要检验的假设，而不
用考虑数据是数值型的还是二元的、样本容量是否平衡、样本方差以及各种其他因素。如
果使用公式，就要了解公式的各种变化形式，这有时很令人困惑。统计学家需要了解公
式，并说明其中的道理，但数据科学家无须如此，他们不用花费力气搞清楚假设检验和置
信区间的具体细节——研究者在准备发表论文时却必须这么做。
本节要点
•
在计算机出现之前，重抽样检验是不现实的，统计学家使用的是标准参照分布。
•
检验统计量可以在标准化之后与参照分布进行比较。
• t
统计量就是一种广泛使用的标准化统计量。
扩展阅读
•
所有统计学导论教科书都会介绍
t
统
计量及其用法。两本比较好的教科书是
David
Freedman
、
Robert Pisani ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.