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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.

The following is a valid probability distribution for a discrete random variable, X: X             4           9            20          P (X)     -0.30      1.0         0.30       

Which one of the following is not an element of descriptive statistical problems?

A university dean is interested in determining the proportion of students who receive some sort of financial aid.  Rather than examine the records for all students, the dean randomly selects 200 students and finds that 118 of them are receiving financial aid.  The dean performs the calculations needed to find a 90% large-sample confidence interval for the true population proportion.  Which one of the following confidence intervals is correct?

An animal scientist is interested in determining the proportion of ewes (i.e., female sheep) that give birth to twins.  Rather than examine the records for all ewes in the United States, the animal scientist randomly selects 500 ewes and finds that 220 of them gave birth to twins. Construct a 99% confidence interval to estimate the true population proportion of ewes, p, who give birth to twins.

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 median age of this sample of 6 students.

The ________ ________ is the set of possible computed values of the test statistic for which the null hypothesis will be rejected.

The table shown below summarizes the 10 winners of the World Series from 1990 to 2000 by division and league.  There was no World Series in 1994 due to a strike by the players.  One of these 10 World Series winners is to be chosen at random.                                                     League                                                   National        American                        Eastern          2                     6 Division           Central          1                     1                         Western        0                     0 Given that the winning team is a member of the National League, what is the probability that the winner plays in either the Central or Western Division?

An experiment results in three possible outcomes, K, L, or M, where P(K) = 0.20, P(L) = 0.30, and P(M) = 0.50.  If P(K|L) = 0.20, are events K and L independent?

It seems reasonable to assume that the number of times a team punts the ball in a football game would be negatively correlated with the number of points that the team scores (i.e., if a team is forced to punt frequently they are probably not moving the ball very well and probably are not scoring many points).  Number of punts (variable X) and number of points scored (variable Y) for a particular team in a random sample of five games are as follows: Number of Punts, X          Number of Points, Y              2                                         35              5                                         14              3                                         21              2                                         21              2                                         28 We want to test our assumption of a negative correlation between number of punts and number of points scored in a football game.  State the appropriate null and alternative hypothesis.