Parking at a large university has become a big problem.  University administrators are interested in determining the average parking time (i.e., the average length of time it takes students to find a place to park on campus) of the students.  An administrator inconspicuously follows 250 students and carefully records their parking times.  Identify the population of interest to the university administration.

A Gallop poll is conducted to estimate the proportion of voters who plan to vote in favor of a certain issue on the ballot.  A random sample of 500 people of voting age is selected.  Results of the poll show that 300 of the 500 people polled plan to vote in favor of the issue.  What is the point estimate of the true population proportion of people who plan to vote in favor of the issue?

A random sample of 4,000 U.S. citizens was asked their opinion concerning gun control.  A total of 2,600 of the 4,000 citizens in the sample stated that they are in favor of gun control legislation.  What is the point estimate of the true population proportion of U.S. citizens who favor gun control legislation?

Assume that a scientist conducts a 2 x 3 factorial experiment.  The Analysis of Variance table is shown below: Source          df          SS               MS               F     Total             17        1.73397 Factor A        1         0.10125       0.10125        23.0375 Factor B        2         0.81195       0.405975       92.3720 A x B             2         0.76803       0.384015       87.3754 Error            12        0.05274        0.004395                                                                                          Based on this analysis and a significance level of α = 0.05, what should the scientist conclude?

The mean length of time required to complete the Columbus Marathon was 4.5 hours.  The standard deviation of the times was 0.50 hours.  Assume that the racing times were approximately normally distributed.  What is the probability that a randomly selected runner completed the race in less than 3.6 hours?

An animal scientist wants to determine the degree of association between carcass quality grade (variable X) and selling price per pound of carcass (variable Y).  The data for a random sample of 10 Angus steer carcasses are shown in the following table. Quality grade, X Carcass price per pound, Y 5 $1.09 7 1.19 4 0.99 5 1.04 8 1.21 6 1.18 4 0.94 7 1.15 8 1.23 6 1.12 The animal scientist performs a hypothesis test using a significance level of 0.05 to determine if the correlation between carcass quality grade and carcass price per pound is greater than zero. Ho:  

Health care issues are receiving a greal deal of attention in both the academic and political arenas.  A sociologist recently conducted a survey of senior citizens whose net worth is too high to quality for Medicaid, but who have no private health insurance.  The ages (in years) of 8 uninsured senior citizens were as follows: Senior Citizen Age 1 66 2 70 3 64 4 88 5 74 6 72 7 87 8 79     Calculate the standard deviation of the ages of these 8 senior citizens.

A statistician evaluated the winning strategies of teams in the National Football League (NFL).  He used actual NFL play-by-play data to approximate the probabilities associated with certain outcomes (e.g., running plays, short pass plays, and long pass plays).  The table below shows the probability distribution for the yardage gained, X, on a running play.  A negative gain represents a loss of yards on the play. Find the probability of gaining 10 or more yards on a running play. X, Yards Gained            Probability                -4                                  0.020        -2                                  0.060        -1                                  0.070          0                                 0.150          1                                 0.130          2                                 0.110          3                                 0.090          4                                 0.070          6                                 0.090          8                                 0.060         10                                0.050         15                                0.085         30                                0.010         50                                0.004         99                                0.001                                                               

We want to use a confidence interval to estimate the proportion of students in the College of Food, Agricultural, and Environmental Sciences that are female.  What sample size would be necessary if we want to estimate the true proportion of female students correct to within 0.03 with probability 0.95?  In an earlier small-scale pilot study, we obtained an estimate of the proportion of female students (p) that was equal to 0.48.

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                                                                                   Identify the experimental units for this experiment.