An industrial psychologist is investigating the effects of work environment on employee attitudes.  A group of 20 recently hired sales trainees were randomly assigned to one of 4 different “home rooms” with 5 trainees per room.  Each room was identical except for the color of the walls.  The 4 colors used were light green, light blue, gray, and red.  Therefore, in this experiment the 4 treatments were the 4 room colors.  The psychologist wants to compare the mean attitudes of the trainees assigned to the 4 rooms with different colors.  At the end of the training program, the attitude of each trainee was measured on a 60 point scale (the lower the score, the poorer the attitude).  The data were subjected to an analysis of variance.  The partially completed Analysis of Variance (ANOVA) table was as follows: Source           df       SS              MS              F     Total                       1,829.75 Treatments             1,678.15 Error                          151.60                                      Find the Mean Squares for error.

A randomized block design was used to compare the mean responses for three treatments.  Four blocks of three homogeneous experimental units were selected, and each treatment was randomly assigned to one experimental unit within each block.  The partially completed ANOVA table for this experiment is as follows: Source               df        SS             MS          F   Total                  11       84.489 Treatments         2       12.032       6.016 Blocks                3       71.749      23.916 Error                  6         0.708        0.118             Do the data provide sufficient evidence to indicate that blocking was effective in reducing variation in the responses?  Use α = 0.05.

A local consumer reporter wants to compare the average costs of grocery items purchased at three different supermarkets – Kroger, Giant Eagle, and Meier.  Prices (in dollars) were recorded for a sample of 60 randomly selected grocery items at each of the three supermarkets.  In order to reduce item-to-item variation, the prices were recorded for each item on the same day at each supermarket. Item                          Kroger    Giant Eagle    Meier     1) Big Thirst Towel      $1.21       $1.49          $1.59 2) Post Golden Crisp    2.78         2.99            3.35 3) Tylenol Tablets         5.98         5.29            5.98           .                              .              .                   .           .                              .              .                   . 59) Colgate Shave       0.94         1.10            1.19 60) Kidney Beans        0.45          0.56            0.38                                                                                   The results of the Analysis of Variance for this experiment are as follows: Source           df       SS            MS          F     Total                       222.21     Supermarket              2.64       1.32       39.23 Item                        215.59       3.65     108.54 Error                           3.97      0.0337                                                                                What are the correct degrees of freedom for total, supermarket, item, and error, respectively?

A randomized block design yielded the following Analysis of Variance table:       Source             df        SS                MS                F Total                 14      836       Treatments        4       501       125.25 Blocks                2       225       112.50 Error                  8       110          13.75                      Find the critical F value from the F tables that should be used to compare to the calculated F value for blocks.  Assume that we will use a significance level (α) of 0.05.

For most populations, sample sizes of n > ________ will be adequate for the sampling distribution of the sample means to be normally distributed.

Independent random samples of 40 Yorkshire litters and 50 Landrace litters are obtained.  For Yorkshires, the mean litter size is 9.0 pigs and the standard deviation of litter size is 2.0 pigs.  For Landrace, the mean litter size is 8.5 pigs and the standard deviation of litter size is 1.8 pigs.  Construct an 80% confidence interval for the difference in population mean litter sizes of Yorkshire and Landrace.

Assume that we have a herd of 50 horses and that we want to select a random sample of 5 of the horses for an experiment.  We begin at row 5 column 1 of a random number table and observe the random numbers shown in the table below.         Col.           1 2 3 4 5 6 Row 5: 37570 39975 81837 16656 06121 91782   6: 77921 06907 11008 42751 27756 53498 Which one of the following is the correct set of 5 randomly selected horses to include in our experiment, assuming that we go from left to right across the rows of random numbers?

The ages (in years) of a sample of 6 students are as follows: Student Age 1 19 2 23 3 20 4 20 5 19 6 19                 Calculate the variance of this sample of 6 student ages.

The weaning weights (in kilograms) of a sample of 6 lambs born and raised on Farmer Jones’ farm are as follows: Lamb Weight 1 30 2 32 3 28 4 42 5 40 6 44 Find the standard deviation of the weaning weights of this sample of 6 lambs.

A farmer weighs his pigs before sending them to market.  The herd average market weight is 250 lb and the standard deviation of the weaning weights is 50 lb.  What is the z-score for a pig that weighs 200 lb?