Ruler :

• Proportion: 4 decimal places
• Percentile: round to the closest whole unit number
• All others: 2 decimal places

APA style

.1 U 1. The weight (in pounds) for a population of school-aged children is normally distributed with a mean equal to 135 :20 pounds (,u i 0). Suppose we select a sample of 100 children to test whether children in this sample have a different weight. Test at the 0.05 level of signicance. a. What are the null and alternative hypotheses? b. What is the critical value for this test? c. What is the mean of the sampling distribution? (1. What is the standard error of the mean for this distribution? 2. A researcher selects a same of n = 30 participants and makes the decision to fail to reject the null hypothesis. She conducts the same study testing the same hypothesis with a sample of n = 300 participants and makes the decision to reject the null hypothesis. Give a likely explanation for why the two samples led to different decisions. 3. Listening to music while taking a test may be relaxing or distracting. We test 49 participants while listening to music and they produce a M = 54.3 6. The mean of the population taking this test without music is u: 50 (o: 12). a. Does listening to music while taking the test lead to a significant difference in scores? Conduct a full hypothesis test using the .05 level of signicance. b. Compute the effect size with Cohen's d c. What is the probability that we made a type I error? What would be the error in terms of independent and dependent variables? d. Is there a risk of a Type II error? e. Summarize your ndings in APA format 4. We measure the self-esteem of a sample of statistics students, reasoning that this course may lower their self-esteem relative to that of the typical college student (u: 55, (I: 11.35)). We obtain the following self-esteem scores: 4-4, 55, 39, 17, 27, 38, 36, 24, 26 a. How would you summarize this data? Explain. b. Does our sample have signicantly different self-esteem scores compared to the typical college student? Conduct a full hypothesis test using the .05 level of significance. c. Compute the effect size with Cohen's d d. What is the probability that we made a type I error? What would be the error in terms of independent and dependent variables? e. Is there a risk of a Type II error? f. Summarize your ndings in APA format 5.. The police chief selects a sample of n = 49 officers from a population of officers with a mean physical fitness rating of 72 17.0 pounds (u + o) on a 100-point physical endurance rating scale. She measures a sample mean physical fitness rating on this scale of M = 74. Conduct a z-test to determine whether physical endurance for the sample is significantly. Test at the .05 level of significance. a. Conduct a complete hypothesis test at the .05 level of significance b. Compute the effect size with Cohen's d c. What is the probability of a Type I error. What would be the error in terms of the independent and dependent variables? d. Is there a risk of a Type II error? e. Summarize your findings in APA format