An educational psychologist is studying two methods of tutoring young children: Method A and Method B. She wants to test whether there is any difference in puzzle solving skills between children tutored by one method versus children tutored by the other. Independent samples of 11 children who were tutored using Method A and 10 children who were tutored using Method B were chosen at random. The Method A children took a mean of 43 minutes to solve a certain puzzle with a standard deviation of 8 minutes. The Method B children took a mean of 42 minutes to solve the same puzzle with a standard deviation of 7 minutes. Assume that the two populations of completion times are normally distributed and that the population varlances are equal. Construct a 90% confidence interval for the difference u,-H, between the mean puzzle-solving times for Method A children (u) and for Method B children (1,). Then find the lower limit and upper limit of the 90% confidence interval. Carry your intermediate computations to at least three decimal places. Round your responses to at least two decimal places. (If necessary, consult a list of formulas.) Lower limit: M Upper limit:

A psychologist finds that fidgety patients tap their fingers on average 500 times during a 2 hour period. You wish to test this claim for the same patients, but in a room decorated with soothing colors and soft lighting. You believe that a warmly decorated room may alter the fidgeting behavior, causing subjects to tap their fingers less than they do under normal conditions. A random sample of 400 patients has a mean of 420 taps and a standard error of 30 taps in a 2 hour period. Find the margin of error for the average tapping of fingers during a 2 hour period.

The coach of a very popular men’s basketball team claims that the average distance the fans travel to the campus to watch a game is 35 miles. The team members feel otherwise. A sample of 16 fans who travel to games was randomly selected and yielded a mean of M= 36 miles and s= 5 miles. Test the coach’s claim at the 5% (.05) level of significance.    one-tailed or two-tailed test:  State the hypotheses: df= tα or t value for the critical region =  sM =    t (test statistic)= Decision:

An educational psychologist is studying two methods of tutoring young children: Method A and Method B. She wants to test whether there is any difference in puzzle solving skills between children tutored by one method versus children tutored by the other. Independent samples of 10 children who were tutored using Method A and 11 children who were tutored using Method B were chosen at random. The Method A children took a mean of 40 minutes to solve a certain puzzle with a standard deviation of 6 minutes. The Method B children took a mean of 44 minutes to solve the same puzzle with a standard deviation of 7 minutes. Assume that the two populations of completion times are normally distributed and that the population variances are equal. Construct a 90% confidence interval for the difference u, - u, between the mean puzzle-solving times for Method A children ( u) and for Method B children (µ,). Then find the lower limit and upper limit of the 90% confidence interval. Carry your intermediate…

Ackerman and Goldsmith (2011) found that students who studied text from printed hardcopy had better test scores than students who studied  text presented on the screen.  In a related study, a professor noticed that several students in a large class had purchased the e-book version of the course textbook.  For the final exam, the overall average for the entire class was μ= 81.7, but the  sample of n = 9 students who used e-books had a mean of M = 77.2 with ((SS =392) Is the sample sufficient to conclude that scores for students using e-books were sufficiently different from scores for the regular class? Use a two-tail test with α= .01.(not .05). Please answer the question using all of the steps presented  on your practice problem assignment.  (null in word, alternative in words, null in symbols, alternative in symbols, critical region t,  df,  all steps in the analysis computing your computed t, make a decision, and give a conclusion.

An educational psychologist is studying two methods of tutoring young children: Method A and Method B. She wants to test whether there is any difference in puzzle solving skills between children tutored by one method versus children tutored by the other. Independent samples of 12 children who were tutored using Method A and 10 children who were tutored using Method B were chosen at random. The Method A children took a mean of 35 minutes to solve a certain puzzle with a standard deviation of 6 minutes. The Method B children took a mean of 33 minutes to solve the same puzzle with a standard deviation of 8 minutes. Assume that the two populations of completion times are normally distributed and that the population variances are equal. Construct a 99% confidence interval for the difference −μ1μ2 between the mean puzzle-solving times for Method A children ( μ1 ) and for Method B children ( μ2 ). Then find the lower limit and upper limit of the 99% confidence interval.…