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 treatments.

Frame score in beef cattle is based on height at the hips and is used as a measure of skeletal size.  Frame scores range from 1 to 10 with a higher number indicating a taller animal.  Independent random samples of frame scores were selected from the Angus and Simmental breeds of beef cattle with the following results: Angus Simmental 5 7 6 7 7 8 5 6 7 7 6   Calculate the Breed Sum of Squares.

In the 1970’s it was generally assumed that the mean birth weight of Angus beef cattle was 75 lb.  A researcher believes that, due to selection for increased size and growth rate in Angus, the average birth weight is now greater than 75 lb.  He obtains a random sample of n = 144 birth weights of Angus calves and calculates a sample mean of 85 lb and a sample standard deviation of 10 lb. Calculate the test statistic needed to test the null hypothesis.

Suppose we want to make an inference about the difference in population proportions (p1 – p2).  For sufficiently large sample sizes, n1 and n2, the mean of the sampling distribution of p1-hat minus p2-hat is equal to __________.

We want to test the hypothesis that the mean number of credit hours taken per semester by OSU undergraduates is less than 16 hours.  Therefore, we obtain a random sample of credit hours for 49 students. The sample mean is 15 hours and the sample standard deviation is 4 hours.  We want to test:    Ho:  μ = 16 hours    Ha:  μ < 16 hours using a significance level (α) = 0.01. What is the calculated value of the test statistic needed to test the null hypothesis in this problem?

Frame score in beef cattle is based on height at the hips and is used as a measure of skeletal size.  Frame scores range from 1 to 10 with a higher number indicating a taller animal.  A randomized block design is used to compare the frame scores of Angus and Simmental calves where the blocks consist of calves of similar ages.  Three blocks are used, where block 1 contains calves that are 320 to 340 days of age, block 2 contains calves that are 341 to 360 days of age, and block 3 contains calves that are 361 to 380 days of age.  The frame scores are as follows:   Angus Simmental Block totals Block 1 5 6 11 Block 2 6 7 13 Block 3 7 8 15 Breed totals 18 21 39 The partially completed ANOVA table for this experiment is as follows: Source   df     SS     MS      F  Total   5.500     Breed   0.167 0.167 0.25 Block   4.000 2.000   Error   1.333 0.667   Calculate the F statistic for blocks.

What assumption is required for estimating the population mean (μ) when we have small samples of n < 30?

The ____________ in an experiment are the factor level combinations that are utilized.

The weaning weights of 3 herds of beef cattle are compared across the 4 seasons of the year.  Thus, this is a 3 x 4 factorial experiment with 3 herds and 4 seasons.  Three calves from each herd are sampled during each season (i.e., there are 3 replications).  The resulting data were analyzed using Analysis of Variance and the partially completed ANOVA table is as follows: Source              df            F            Total                  35 Herd                   2         17.2 Season               3          3.0 Herd x Season    6          1.2 Error                  24                              Was there a significant herd x season interaction?  Use a significance level of α = 0.05.

You are interested in purchasing a new car.  One of the many points you wish to consider is the resale value of the car after 5 years of ownership.  Since you are particulary interested in a certain foreign sedan, you decide to estimate the resale value of this car with a 90% confidence interval.  You manage to obtain data on 16 recently resold 5-year-old foreign sedans of that model.  These 16 cars were resold at an average price of $10,000 with a standard deviation of $1,500. You estimate the true population mean for the resale value of this model of foreign car using a 90% confidence interval.  What assumption must be met in order for the confidence interval that you constructed to be valid?