求英语帝……

zjr1990222

A human resources department has developed a series of tests to evaluate how suitable a potential employee is for leadership positions. From past data they have found that 20% of applicants are not suited to leadership positions. Through analysing historical data they have found that 90% of those who are not suited to leadership show up through their tests and are identified as not suitable. (Correct positive) The tests also miss about 10% of the people who really are suitable for leadership positions but are not identified as such. (False positive).

作业~实在读不明白……我算出来的东西跟答案也不一样……

Devourment

老托，你有没有感觉我很萌

小拖泥

奶子 你突然显得特纯良

灰暗的贝壳

姜医生好
Devourment 发表于 2011-4-22 23:06

这是拍到腿上去了~~~~~~？

灰暗的贝壳

MM冷静点~
记得你以前的帖子说你过段时间就去找你的亲爱的啦~不过这么火爆的情绪是会出事的~嘿嘿~
zjr1990222 发表于 2011-4-22 20:25

本人只对亲爱的没脾气~~~ 。。  不过你怎么这么八卦~~~

shot

怎么跑着个帖子里面来了？？

Devourment

28# Devourment  
斑竹很有两下。还反复解释。我木看懂，但我可以看到斑竹的热心和友善
大煎荷包蛋 发表于 2011-4-22 23:04

姜医生好

大煎荷包蛋

28# Devourment
斑竹很有两下。还反复解释。我木看懂，但我可以看到斑竹的热心和友善

zjr1990222

他确实耐心大发了！！！这要是我一撮子把你撮出去鸟～～
灰暗的贝壳 发表于 2011-4-22 19:54

MM冷静点~
记得你以前的帖子说你过段时间就去找你的亲爱的啦~不过这么火爆的情绪是会出事的~嘿嘿~

lzh47

我靠，人才啊大奶，简称，人奶！

灰暗的贝壳

谢谢~我发现我的理解错误在哪里了~
我以为那个20%指的是这次测试表明的适合不适合的人~（以为一次性的测试是有误差的~而不是一系列的的~而后面的10%跟90%都是说在纠正误差的~没仔细看到a series of tests）

...
zjr1990222 发表于 2011-4-22 19:46

他确实耐心大发了！！！这要是我一撮子把你撮出去鸟～～

Devourment

木有事- -
看题目要仔细呀T___T

zjr1990222

我从头到尾给你解释一遍，这次解释你要看不懂我觉得你真得要好好的学数学了……我哪里有错请指出并批判



1.Out of 1000 people, how many are suited to leadership positions?
一千人里有多少是合适的？
...
Devourment 发表于 2011-4-22 19:08

谢谢~我发现我的理解错误在哪里了~
我以为那个20%指的是这次测试表明的适合不适合的人~（以为一次性的测试是有误差的~而不是一系列的的~而后面的10%跟90%都是说在纠正误差的~没仔细看到a series of tests）

所以我做的时候算出了800以后  再做第二问的时候乘以了1-90%…………
也导致了后面的问题也不能理解
谢谢你~这么耐心

Devourment

我从头到尾给你解释一遍，这次解释你要看不懂我觉得你真得要好好的学数学了……我哪里有错请指出并批判



1.Out of 1000 people, how many are suited to leadership positions?
一千人里有多少是合适的？

题目里说了根据历史数据有百分之二十的人最终表明不适合，这根这个test完全没关系，是多少就是多少，所以是总人数*适合率1000*(1-20%)=800

2.Out of the suitable people, how many will be correctly identified as suitable?  
合适的人里多少是被该测试正确判定的？


题目里说这个测试miss掉了百分之十本该合适却被判定为不合适的，所以判定正确率为90%，所以=总适合人数*判定正确率=800*(1-10%)=720


3.Out of the 1000 people, how many are not suitable?  
一千个人里有多少是不合适的?


我觉得你概念没有理清楚，这种题只有是和非两种options，就跟你不是男的就是女的一样，除去不合适的当然是合适的了，所以是1000-800=200人


4.Out of the unsuitable people, how many will be falsely identified as suitable?
这些不合适的人里有多少是被该测试判定为合适的？

上面说了，miss掉了百分之10的人，所以=不适合人数*判定错误率=200*(1-90%)=20



5.In total, how many people will be identified as suitable?  
所以总共有多少人会被判定为适合？

很简单，根据上面，总人数=正确判定适合人数+不正确判定为合适人数=720+20=740


6.Out of those identified as suitable, what percentage will really be unsuitable.  
在被判定为适合的人里，有百分之多少的人是不适合的？
20/740*100=2.7%，这不用我说了吧？



7.Out of those identified as unsuitable, what percentage will be suitable?  
被判断为不适合的人里，有百分之多少其实是适合的？


根据第五题，被判断不适合的人数=1000-740=260，所以=误判人数/总不适合人数=80/260=30.8%


8.Clementine was identified as suitable for a leadership position. How likely is it that she really is?  % (to 1d.p) likely.
Clementine被判断为适合属性，她其实有多少的概率是真的适合？
100-2.7=97.3%不用我说了吧


9.Pita failed the test, but insists that he would do well in a leadership position. What is the probability (as a percentage) that he is correct and would be suited to leadership?
Pita没通过这个测试，但是他坚持说他在实践中很牛逼。所以说他确实是很牛逼的概率是多少？

这个跟第七题完全就是一个问题

Devourment

26# zjr1990222


我哪里做错了欢迎指出来，洗耳恭听伸手党教诲。
另外10%跟90%当然加起来要等于一百根本不需要“巧合的”，除了适合和不适合难道还有第三种属性？

zjr1990222

[quote]Out of 1000 people, how many are suited to leadership positions?
一千人里有多少是合适的？
1000*(1-20%)=800

Out of the suitable people, how many will be correctly identified as suitable?  
合适的 ...
Devourment 发表于 2011-4-22 14:5

那个…你貌似说错了  
因为我同学做的题目是一样的 只是数据不同而已
我做的题目里面10%跟90%巧合加起来的等于100%
我同学做的那个不是……所以……模仿我的……做错了……呵呵……

skylaughing

21# zjr1990222

Actually you can use 90% directly. Using (1-10%) just show your understood that 1 representing the total who are not suitable for leadership, and 10% is the rest of 800. this 10% are not identified as not suitable through their test which is also the error of the data. Is that clear?

zjr1990222

版主大人生气了{:7_365:}

zjr1990222

…………怎么还成我的错了………………我对不起你好么………………
Devourment 发表于 2011-4-22 15:25

……别这样啦……我只想啦~
每个字符都有他的意思~

就像每个人都是要死的·但是人生中没过经历过的东西都不一样才成就了每个人独特的人生

数学嘛~只有答案是不行的啦{:7_366:}

Devourment

那你直接乘以90%就好了……为什么要用1-10%
我还在想10%是神马东西……
zjr1990222 发表于 2011-4-22 15:24

…………怎么还成我的错了………………我对不起你好么………………

zjr1990222

不会吧……

90% of those who are not suited to leadership show up through their tests and are identified as not suitable

你看题了没…………………………
Devourment 发表于 2011-4-22 15:20

那你直接乘以90%就好了……为什么要用1-10%
我还在想10%是神马东西……

Devourment

Out of the suitable people, how many will be correctly identified as suitable?  
合适的人里多少是被该测试正确判定的？
800*(1-10%)=720)
为啥
zjr1990222 发表于 2011-4-22 15:19

不会吧……

90% of those who are not suited to leadership show up through their tests and are identified as not suitable

你看题了没…………………………

zjr1990222

Out of the suitable people, how many will be correctly identified as suitable?  
合适的人里多少是被该测试正确判定的？
800*(1-10%)=720)
为啥

Devourment

吞吐帝很strong。。。。
1q2a 发表于 2011-4-22 15:15

我是这会儿实在蛋疼了

1q2a

吞吐帝很strong。。。。

Devourment

我还当是交集补集的统计问题呢= =搞了半天就是概率………………

Devourment

Out of 1000 people, how many are suited to leadership positions?
一千人里有多少是合适的？
1000*(1-20%)=800

Out of the suitable people, how many will be correctly identified as suitable?  
合适的人里多少是被该测试正确判定的？
800*(1-10%)=720

Out of the 1000 people, how many are not suitable?  
一千个人里有多少是不合适的?
1000-800=200

Out of the unsuitable people, how many will be falsely identified as suitable?
这些不合适的人里有多少是被该测试判定为合适的？
200*(1-90%)=20

In total, how many people will be identified as suitable?  
所以总共有多少人会被判定为适合？
720+20=740

In total, how many people will be identified as suitable?
这俩是一个问题

Out of those identified as suitable, what percentage will really be unsuitable.  
在被判定为适合的人里，有百分之多少的人是不适合的？
20/740*100=2.7%

Out of those identified as unsuitable, what percentage will be suitable?  
被判断为不适合的人里，有百分之多少其实是适合的？
80/260=30.8%


Clementine was identified as suitable for a leadership position. How likely is it that she really is?  % (to 1d.p) likely.
Clementine被判断为适合属性，她其实有多少的概率是真的适合？
100-2.703=97.3%


Pita failed the test, but insists that he would do well in a leadership position. What is the probability (as a percentage) that he is correct and would be suited to leadership?
Pita没通过这个测试，但是他坚持说他在实践中很牛逼。所以说他确实是很牛逼的概率是多少？

这个跟上上一道是一个题

TheSuede

奶粉翻译的是对的。。。这不难读懂把

zjr1990222

你这大学生不应该看不懂吧
你这句的意思是在这些适合的人里有多少是被正确判断为适合的
Devourment 发表于 2011-4-22 14:29

我看得明白~只是后面那么多问题~我反而看的不明白了……

zjr1990222

正确答案 分别是
800
720
200
20
740
260
2.7%
30.8%
97.3%
30.8%