Question

REVIEW QUESTIONS Ctr *13.5 A library system lends books for periods of 21 days. This policy is being reevaluated in view of a possible new loan period that could be either longer or shorter than 21 days. To aid in making this decision, book-lending records were consulted to determine the loan periods actually used by the patrons. A random sample of eight records revealed the following loan periods in days: 21, 15, 12, 24, 20, 21, 13, and 16. Test the null hypothesis with t, using the .05 level of significance. Answers on pages 436 and 43:7. 13.6/It's well established, we'll assume, that lab rats require an average of 32 trials in a complex water maze before reaching a learning criterion of three consecutive error- less trials. To determine whether a mildly adverse stimulus has any effect on per- formance, a sample of seven lab rats were given a mild electrical shock just before each trial. (a) Given that X-34.89 and s 3.02, test the null hypothesis with t,using the 05 level of significance. (b) Construct a 95 percent confidence interval for the true number of trials required to learn the water maze. (c) Interpret this confidence interval. 13.7 Is the temperature of the earth getting warmer because heat is trapped by green- house gas emissions, such as carbon dioxide, in the earth's atmosphere? The

Answer 1

We have to perform t test for testing of population mean

First we calculate t test statistic value and then t critical value , then we will compare them and make decision.

In part b) and c), calculate the confidence interval and then interpret