开发者:上海品职教育科技有限公司 隐私政策详情

应用版本:4.2.11(IOS)｜3.2.5(安卓)APP下载

返回

想做蜜蜂的猫咪 · 2022年09月24日

在视频中老师提到可以用bayes只有在两种情况下，这道题是两种吗，不是3种吗，股票还有表现好中坏之分

  1. CFA I
  2. Quantitative

NO.PZ2015120604000076

问题如下：

According to the above table, and we are informed that the performance of next day is good, what is the probability of today's performance is good?

选项：

A.

0.74.

B.

0.28.

C.

0.67.

解释：

C is correct.

We can use Bayes' formula to solve this problem.

A: today's performance is good.

B: next day's performance is good.

P(A|B)=P(B|A)*P(A)/P(B)=0.7×0.4/(0.4×0.7+0.2×0.3+0.4×0.2)

P(B|A)*P(A)=0.7×0.4=0.28

P(B)=0.4×0.7+0.2×0.3+0.4×0.2=0.42

P(A|B)=0.67

在视频中老师提到可以用bayes只有在两种情况下，这道题是两种吗，不是3种吗，股票还有表现好中坏之分

添加评论
1 个答案

星星_品职助教 · 2022年09月25日

同学你好，

两种是90%以上题目的情况。三种也可以，只要是这种分叉的形式都可以用。

  • 1

    回答

  • 0

    关注

  • 340

    浏览
相关问题

NO.PZ2015120604000076问题如下 Accorng to the above table, anwe are informeththe performanof next y is goo whis the probability of toy's performanis goo A.0.74.B.0.28.C.0.67. C is correct.We cuse Bayes' formula to solve this problem.toy's performanis goonext y's performanis gooP(A|B)=P(B|A)*P(A)/P(B)=0.7×0.4/(0.4×0.7+0.2×0.3+0.4×0.2)P(B|A)*P(A)=0.7×0.4=0.28P(B)=0.4×0.7+0.2×0.3+0.4×0.2=0.42P(A|B)=0.67 我的理解贝叶斯公式是P（A｜B）=P（B｜A）*P（A）/P（B），P（B｜A）=0.4*0.7，P（B）=0.4*0.7+0.2*0.3+0.4*0.2=0.42，P（A）=0.4，但是这样算下来跟答案不一样，是不是P（A）错了？

2024-07-25 12:03 2 · 回答

NO.PZ2015120604000076 问题如下 Accorng to the above table, anwe are informeththe performanof next y is goo whis the probability of toy's performanis goo A.0.74. B.0.28. C.0.67. C is correct.We cuse Bayes' formula to solve this problem.toy's performanis goonext y's performanis gooP(A|B)=P(B|A)*P(A)/P(B)=0.7×0.4/(0.4×0.7+0.2×0.3+0.4×0.2)P(B|A)*P(A)=0.7×0.4=0.28P(B)=0.4×0.7+0.2×0.3+0.4×0.2=0.42P(A|B)=0.67 这个题目有问题吧？题目的意图是想考察条件概率，但是问法并不是，问的就是一个独立事件的概率。

2024-07-14 16:47 1 · 回答

NO.PZ2015120604000076 问题如下 Accorng to the above table, anwe are informeththe performanof next y is goo whis the probability of toy's performanis goo A.0.74. B.0.28. C.0.67. C is correct.We cuse Bayes' formula to solve this problem.toy's performanis goonext y's performanis gooP(A|B)=P(B|A)*P(A)/P(B)=0.7×0.4/(0.4×0.7+0.2×0.3+0.4×0.2)P(B|A)*P(A)=0.7×0.4=0.28P(B)=0.4×0.7+0.2×0.3+0.4×0.2=0.42P(A|B)=0.67 这个题用贝叶斯公式怎么画图啊

2023-07-23 20:17 1 · 回答

NO.PZ2015120604000076 问题如下 Accorng to the above table, anwe are informeththe performanof next y is goo whis the probability of toy's performanis goo A.0.74. B.0.28. C.0.67. C is correct.We cuse Bayes' formula to solve this problem.toy's performanis goonext y's performanis gooP(A|B)=P(B|A)*P(A)/P(B)=0.7×0.4/(0.4×0.7+0.2×0.3+0.4×0.2)P(B|A)*P(A)=0.7×0.4=0.28P(B)=0.4×0.7+0.2×0.3+0.4×0.2=0.42P(A|B)=0.67 如题

2023-01-26 23:24 1 · 回答

NO.PZ2015120604000076 问题如下 Accorng to the above table, anwe are informeththe performanof next y is goo whis the probability of toy's performanis goo A.0.74. B.0.28. C.0.67. C is correct.We cuse Bayes' formula to solve this problem.toy's performanis goonext y's performanis gooP(A|B)=P(B|A)*P(A)/P(B)=0.7×0.4/(0.4×0.7+0.2×0.3+0.4×0.2)P(B|A)*P(A)=0.7×0.4=0.28P(B)=0.4×0.7+0.2×0.3+0.4×0.2=0.42P(A|B)=0.67 老师，这个式子完全没看懂，麻烦一下每一步。谢谢

2022-12-01 06:54 1 · 回答