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Old 09-30-2016, 10:18 AM
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rgreenlee rgreenlee is offline
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Default Hypothetical Exam question

I took this exam awhile back, but I ran across something that I wanted to check...it reminded me of a problem on the easier scale of questions one might run into on this exam.

What is the 95% confidence interval of the average of 14 independent uniformly (0,1) distributed numbers?

Is it (.34878,.65122)

(sketch: st dev of the average = .077151675, 1.96 standard deviations away from mean)
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Old 09-30-2016, 10:53 AM
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I believe that checks out, yeah
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Old 09-30-2016, 02:24 PM
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I got the same answer as well
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Old 10-02-2016, 12:00 AM
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U(0,1) --- mean=1/2 variance=1/12
14 independent--- mean=14/2 var=14/12
ave--- mean/n var/n

I don't get it anyone can explain the solution? thanks

"ave of 14 independents"
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Old 10-02-2016, 01:44 AM
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Old 10-02-2016, 04:52 AM
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Quote:
Originally Posted by Z3ta View Post
Well put. For this exam I'd recommend just knowing that VAR(X_bar)=VAR(X)/n
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Old 10-02-2016, 01:48 PM
StayCoolKD StayCoolKD is offline
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Quote:
Originally Posted by StayCoolKD View Post
U(0,1) --- mean=1/2 variance=1/12
14 independent--- mean=14/2 var=14/12
ave--- mean/n var/n

I don't get it anyone can explain the solution? thanks

"ave of 14 independents"
ok thanks! I made mistake on the expected value: E(X_bar)=E[X]
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