# 112 what are the upper and lower bounds of the 95 ci

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1.12What are the upper and lower bounds ofthe 95% CI for(expressed now as a
percent)1.13Is the election outcome for Cameron’sparty in the 95% CI?no
1.14What statistical principle is this anexample of?
Practice Final3Problem 2 Confidence IntervalsMatch the margin of error to the desired CI.Desired CIAnswerMargin of Error2.195% CI for a mean,𝜎known51.?0.975(?) ∗ (?√1?+(?−?̅)2∑(?𝑖−?̅)2)2.280% CI for 2-sampledifference in means,pooled variance32.?0.9(?) ∗ (√?12?1+?22?2)2.380% CI for 2-sampledifference in means,unpooled variance23.?0.9(?) ∗ (??1?1+1?2)2.495% prediction intervalfor?̂|?44.?0.975(?) ∗ (?√1 +1?+(?−?̅)2∑(?𝑖−?̅)2)2.595% CI for?|?15.?0.975∗ (𝜎𝑋√?)
Practice Final4Problem 3.Hypothesis tests3.1Suppose we want to test the hypothesis0:0 vs.:0aHH𝜎unknown and N =50.If we want05.0We would reject the null when:1.0.975(49)( )xtSE x2.05.0)(zxSEx3.0.95(50)( )xtSE x4.0.95(49)( )xtSE x3.2Suppose we want to test the hypothesis0:0 vs.:0aHH,𝜎unknown and N =100.If we want05.0We would reject the null when:1.0.95(100)( )xtSE x2.0.90(100)( )xtSE x3.0.05(99)( )xtSE x4.0.975(99)( )xtSE x3.3Suppose we want to test the hypothesis0:10H, vs1:0aHN=500If we want01.0We would reject the null when:1.10.991(499)()btSE b2.10.991(500)()btSE b3.10.9951(498)()btSE b4.99.011)(zbSEb3.4Suppose we want to test the hypothesis0:10H, vs1:0aHN=500If we want01.0We would FAIL TO reject the null when:1.10.991(500)()btSE b2.10.011(498)()btSE b3.10.991(499)()btSE b4.10.951()bzSE b
Practice Final5Problem 4.Inference for proportionsThe Department of Statistics estimates that 50% of students at the University of Washington will have takenSTAT 311 by the time they graduate.You believe it is less than 50%, and decide to take a survey of graduatingseniors to estimate the true proportion.Your friend gets you a list of the graduating seniors and their emailaddresses, and you randomly select a sample of n=200, email them, and ask them to report on a Catalystsurvey whether they have taken STAT 311:40% of seniors report that they have.Set up a 90% CI for the estimated proportion of seniors who have taken STAT 311.4.1Symbolic representation:?̂ ± ?𝛼/2∗ √?̂ (1−?̂)?or? = ± ?𝛼/2∗ √?̂ (1−?̂)?4.2With plug-in values:0.40 ± 1.64 ∗ √0.4(1−0.4)200= 0.40 ± 0.06 or [0.34, 0.46]State the null and the general alternative hypotheses. What is the approximate distribution of the sampleproportion under the null hypothesis?

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