# What are the upper and lower bounds of the 95 ci for

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1.12What are the upper and lower bounds of the 95% CI for (expressed now as a percent)
1.13Is the election outcome for Cameron’s party in the 95% CI?
1.14What statistical principle is this an example of?
Practice Final 3 Problem 2 Confidence Intervals Match the margin of error to the desired CI. Desired CI Answer Margin of Error 2.195% CI for a mean, 𝜎known 5 1.?0.975(?) ∗ (?√1?+(?−?̅)2∑(?𝑖−?̅)2)2.280% CI for 2-sample difference in means, pooled variance 3 2.?0.9(?) ∗ (√?12?1+?22?2)2.380% CI for 2-sample difference in means, unpooled variance 2 3.?0.9(?) ∗ (??1?1+1?2)2.495% prediction interval for ?̂|?4 4.?0.975(?) ∗ (?√1 +1?+(?−?̅)2∑(?𝑖−?̅)2)2.595% CI for ?|?1 5.?0.975∗ (𝜎𝑋√?)
Practice Final 4 Problem 3. Hypothesis tests
Practice Final 5 Problem 4. Inference for proportions The Department of Statistics estimates that 50% of students at the University of Washington will have taken STAT 311 by the time they graduate. You believe it is less than 50%, and decide to take a survey of graduating seniors to estimate the true proportion. Your friend gets you a list of the graduating seniors and their email addresses, and you randomly select a sample of n=200, email them, and ask them to report on a Catalyst survey 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 sample proportion under the null hypothesis?