统计问题求教
- 主题发起人 ccc
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- 2003-04-13
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新的统计问题
统计局老师帮忙看看。
See the table below to anser the questions --
1)
How large was the sample in the above study (refer to Table 1)?
a) 2
b) 5
c) 7
d) 8
2)
What is the computed value of F for the global test and what should you conclude (refer to Table 1)?
a) F is 28.38, which means some of the regression coefficients do not equal 0
b) F is .002, which means all the independent variables are 0.
c) F is 7.43, which means all the regression coefficients are 0
d) none of the above
3)
Which of the following independent variables should be dropped from the regression equation (refer to Table 1)?
a) X1
b) X2
c) Neither
d) Both
4)
Determine the coefficient of determination (refer to Table 1).
a) .413
b) 28.38%
c) .645
d) .919
5)
How many independent variables were considered (refer to Table 1)?
a) 2
b) 5
c) 1
d) 3
统计局老师帮忙看看。
See the table below to anser the questions --
1)
How large was the sample in the above study (refer to Table 1)?
a) 2
b) 5
c) 7
d) 8
2)
What is the computed value of F for the global test and what should you conclude (refer to Table 1)?
a) F is 28.38, which means some of the regression coefficients do not equal 0
b) F is .002, which means all the independent variables are 0.
c) F is 7.43, which means all the regression coefficients are 0
d) none of the above
3)
Which of the following independent variables should be dropped from the regression equation (refer to Table 1)?
a) X1
b) X2
c) Neither
d) Both
4)
Determine the coefficient of determination (refer to Table 1).
a) .413
b) 28.38%
c) .645
d) .919
5)
How many independent variables were considered (refer to Table 1)?
a) 2
b) 5
c) 1
d) 3
附件
- 注册
- 2003-04-13
- 消息
- 241,187
- 荣誉分数
- 37,900
- 声望点数
- 1,393
统计局该出手了吧 ？
- 注册
- 2010-07-14
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Let c(n,k) denote the number of different ways of picking k numbers from a set of n numbers. (a.k.a, "n choose k").
The probability of hitting x number in 649 is
c(6,x)*c(49-x, 6-x)/c(49,6).
Denote this number by p(x). On average, we will hit
p(0)*0+ p(1)*1+ p(2)*2 + ... + p(6)*6 numbers.
有计算器的帮忙算一下。觉得俺牛的给俺加个声望哈。
- 注册
- 2003-04-13
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这个式子有点小错误吧？应该是
c(6,x)*c(43, 6-x)/c(49,6).
对上 0 ~ 6 个数字的概率分别为
p(0) = 0.4360
p(1) = 0.4130
p(2) = 0.1324
p(3) = 1.765 e-002
p(4) = 9.686 e-004
p(5) = 1.845 e-005
p(0) = 7.151 e-008
也就是说，一个数也对不上的可能性是 43.6%。对上 3 个数的可能性是 1.77%。中全奖的可能性约为一千四百万分之一。买一次平均对上 0.7467 个数。
应该是 1400 万，不是 140 万。
