The PTA at Central High School is concerned that students who graduate from the school do not score well on mathematics achievement tests, on average, as to students from other schools in the district. The mean score for students in the larger school district is 98. The school principal randomly selects 15 students from the graduating class and administers the standardized mathematics achievement test. The scores of the 15 students from Central High are as follows:
105, 98, 101, 110, 96, 103, 104, 101, 98, 105, 112, 95, 105, 100, 108
(a) Formally state the hypothesis necessary to conduct a non-directional test.
(b) Complete the test at the 05 level of significance, and state your conclusions in English.
(c) Construct and interpret the 95% confidence interval around the sample mean.
(d) Compute the effect size Hedge's g