Question

PSY 3200 Unit 84 AS: Hypothesls Testing for Distribution of Means In this assignment studlents will demonstrate thelr understanding of the distribution of means doing all steps of hypothesls testing. For eadh probiem students will write out all steps of hypothesis testing indluding populations, hypotheses, outoff scores, and all relevant calculations. Assignments will be typed and uploaded in a word document to blackboard 1. A nationwide survey in 1995 revealed that U.S grade-school children spend an average of u R4hars per week dolng homework. The distribution b normal with σ . 3.2. Last year, a sample of n 100 grade school children was given the same survey. For thies sample, the mean number of homework hours was 7.1. Has there been a significant change in the homework habits of gradeschool children? Test with α..05. On the basis of her newly developed technique, a student belleves she can reduce the amount of time schizophrenics spend in an institution. As director of training at a nearby institution, you agree to let her try her method on 20 schizophrenics, randomly sampled from your institution. The mean duration that schizophrenics stay at your institution is 85 weeks, with a standard deviation of 15 weeks. The scores are normally distributed. The results of the experiment show that patients treated by the student stay at the institution a mean duration of 78 weeks. What do you conclude about the student's technique? Use a 05. 3. A psychologist has developed a standardized test for measuring the vocabulary skills of 4-y old children. The scores on the test form a normal distribution with μα 60 ando»10.A researcher would like to use this test to investigate the idea that children who grow up with no siblings develop vocabulary skills at a different rate than children in large families. A sample of n 25 children is obtained, and the mean test score for this sample is 63. On the basis of this sample, can the researcher conclude that vocabulary skills for children with no siblings are significantly different from those of the general population? Test at the 01 level of significance. The average age for licensed drivers in a county is 42.6, with a standard deviation of 12, and the dstribution is approximately normal. A county police officer was interested in whether the average age of those receiving speeding tickets is less that the average age of the population who has a license She obtained a sample of 16 drivers with speeding tickets. The average age for this sample was 344. Do all the steps of hypothesis testing using the 0:01 significance level

Answer 1