A student was asked to find a 98% confidence interval for widget width using data from a random sample of size n = 19. Which of the following is a correct interpretation of the interval 12.3

A student was asked to find a 99% confidence interval for widget width using data from a random sample of size n = 26. Which of the following is a correct interpretation of the interval 11.3 < μ < 20.4? Check all that are correct. The mean width of all widgets is between 11.3 and 20.4, 99% of the time. We know this is true because the mean of our sample is between 11.3 and 20.4. With 99% confidence, the mean width of all widgets is between 11.3 and 20.4. With 99% confidence, the mean width of a randomly selected widget will be between 11.3 and 20.4. There is a 99% chance that the mean of the population is between 11.3 and 20.4. There is a 99% chance that the mean of a sample of 26 widgets will be between 11.3 and 20.4.

A graduate student is interested in how viewing different types of scenes affects working memory. For his study, he selects a random sample of 36 adults. The subjects complete a series of working memory tests before and after walking in an urban setting. Before the walk, the mean score on the test of working memory was 9.1. After the walk, the mean score was 1.4 higher. The graduate student has no presupposed assumptions about how viewing different types of scenes affects working memory, so he formulates the null and alternative hypotheses as: H00 : μDD = 0 H11 : μDD ≠ 0 Assume that the data satisfy all of the required assumptions for a repeated-measures t test. The graduate student calculates the following statistics for his hypothesis test: Mean difference (MDD) 1.4 Estimated population standard deviation of the differences (s) 1.6 Estimated standard error of the mean differences (sMDMD) 0.2667 Degrees of freedom (df) 35 The t statistic 5.25 The critical values of t…