# Is this a one tail or two tail test circle one 48 we

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4.7 Is this a one-tail or two-tail test? (circle one)
Practice Final 6 (circle one) (fill in value) You want to calculate the power of this test against your alternative hypothesis, that the true proportion is 25%. To do this, you will need to calculate ? ???? -- the critical value of p under the null hypothesis for α=0.05. .
Draw the distributions of the null and the specific alternative hypothesis, and label each. Label the following values of on the x axis: ? 0 , ? 𝐴 , ? ???? (IMPORTANT EACH OF THESE LABELS WILL BE WORTH 1 POINT). Shade in the appropriate area that represents the power of the test. The drawing does not have to be the right scale, but the ordering of the values on the axis needs to be correct.
Practice Final 7 Set up the formula for calculating power, and plug in the values. 4.11 Formula for the power of this test: ????? = ?? ( 𝑍 < ? ???? − ? 𝐴 ? 𝐴 (1 − ? 𝐴 ) ? ) 4.12 With plug in values: ?? ( 𝑍 < 0.29 − 0.25 0.25 (1 − 0.25) 200 ) = 0.9
Practice Final 8 Problem 5. Statistical inference for means Newly developed diet pills are known to work differently for men and for women. A sample of 120 subjects (50 males, 70 females) participated in this study, in which their pre- and post-treatment weights were measured: Male (N=50) Female (N=70) Pre Post Difference Pre Post Difference mean 207 202 -5 165 155 st dev 8 6 10 9 Our first goal is to test the claim that there is an effect of the diet pills for females. Let ? ̅ 𝑓 be the sample mean difference for females, and ?(? ̅ 𝑓 ) be the population parameter: -10 12 15 𝐻 0 : ?(? ̅ ? ) = 0 vs 𝐻 𝑎 : ?(? ̅ ? ) < 0 5.1 Is this a paired sample or independent samples test? (circle one) Set up the appropriate test statistic for this test. 5.2 Formula for the test statistic: ? = ? ̅ 𝑓 − 0 ? ?? √?? 5.3 Plug in and solve : ? = −10 15 √70 = −5.58 5.4 What is the distribution of this test statistic? Show the reference distn, df and whether to use or /2 t -distribution with df = n f -1 = 69 or ?(69) & use α 5.5 Is this is a 1 or 2 tailed test? 1-Tail 5.6 What is the critical value of the test statistic for ? = 0.01 ? ???? = ? 0.01 (69) = −2.38 5.7 What is your decision? Reject 𝐻 0 since ? = −5.6 < −2.38 = ? ????
Practice Final 9 Test the claim that effects of the diet pills are same for males and for females. Note that now the pre-post weight differences for each sex are the two random variables.
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