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.
统计实验与显著性检验
｜
99
3.
记录下四个组中每个组的均值。
4.
记录下四个组均值之间的方差。
5.
重复第
2~4
步多次，比如
1000
次。
重抽样方差超过观测方差的次数的比例是多少？这个比例就是
p
值。
这种置换检验比
3.3.1
节中的检验要复杂一些
。幸运的是，
lmPerm
包中的
aovp
函数可以计
算这种置换检验：
> library(lmPerm)
> summary(aovp(Time ~ Page, data=four_sessions))
[1] "Settings: unique SS "
Component 1 :
Df R Sum Sq R Mean Sq Iter Pr(Prob)
Page 3 831.4 277.13 3104 0.09278 .
Residuals 16 1618.4 101.15
---
Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
由
Pr(Prob)
给出的
p
值是
0.09278
。换句话说，给定同样的黏性，对于四个网页的响应率
来说，仅由随机因素造成的差异与实际观测差异一样大的概率是
9.3%
。传
统上认为不太可
能发生的统计阈值是
5%
，而这个概率高于
5%
，所以我们得出结论
，四个网页之间的差异
应该是由随机因素造成的。
Iter
列给出了置换检验中的迭代次数，其他列对应于传统的
ANOVA
表格，我们将在后面
进行介绍。
在
Python
中，可以使用以下代码计算置换检验。
observed_variance = four_sessions.groupby('Page').mean().var()[0] ...
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.