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Consider a completely randomized experiment in which a control group is given a placebo for congestion relief and a treatment group is given a new drug for congestion relief. Describe a double-blind procedure for this experiment and discuss some benefits of such a procedure.

Are data at the nominal level of measurement quantitative or qualitative?

How would you use a completely randomized experiment in each of the following settings? Is a placebo being used or not? Be specific and give details. (a) A veterinarian wants to test a strain of antibiotic on calves to determine their resistance to common infection. In a pasture are 22 newborn calves. There is cnough vaccine for 10 calves. However, blood tests to determine resistance to infection can be done on all calves. (b) The Denver Police Department wants to improve its image with teenagers. \(\mathrm{A}\) uniformed officer is sent to a school one day a week for 10 weeks. Each day the officer visits with students, eats lunch with students, attends pep rallies, and so on. There are 18 schools, but the police department can visit only half of these schools this semester. A survey regarding how teenagers view police is sent to all 18 schools at the end of the semester. (c) A skin patch contains a new drug to help people quit smoking. A group of 75 cigarette smokers have volunteered as subjects to test the new skin patch. For one month, 40 of the volunteers receive skin patches with the new drug. The other volunteers receive skin patches with no drugs. At the end of two months, each subject is surveyed regarding his or her current smoking habits.

Use a random-number table to generate a list of eight random numbers from 1 to \(976 .\) Explain your work.

Use a random-number table to simulate the outcomes of tossing a quarter 25 times. Assume that the quarter is balanced (i.e., fair).

Die A die is a cube with dots on each face. The faces have \(1,2,3,4,5\), or 6 dots. The table below is a computer simulation (from the software package Minitab) of the results of rolling a fair die 20 times. $$ \begin{aligned} &\text { DATA DISPLAY }\\\ &\begin{array}{c|cccccccccc} \text { ROW } & \text { C1 } & \text { C2 } & \text { C3 } & \text { C4 } & \text { C5 } & \text { C6 } & \text { C7 } & \text { C8 } & \text { C9 } & \text { C10 } \\ \hline 1 & 5 & 2 & 2 & 2 & 5 & 3 & 2 & 3 & 1 & 4 \\ 2 & 3 & 2 & 4 & 5 & 4 & 5 & 3 & 5 & 3 & 4 \end{array} \end{aligned} $$ (a) Assume that each number in the table corresponds to the number of dots on the upward face of the die. Is it appropriate that the same number appears more than once? Why? What is the outcome of the fourth roll? (b) If we simulate more rolls of the die, do you expect to get the same sequence of outcomes? Why or why not?

Modern Managed Hospitals (MMH) is a national for-profit chain of hospitals. Management wants to survey patients discharged this past year to obtain patient satisfaction profiles. They wish to use a sample of such patients. Several sampling techniques are described below. Categorize each technique as simple random sample, stratified sample, systematic sample, cluster sample, or convenience sample. (a) Obtain a list of patients discharged from all MMH facilities. Divide the patients according to length of hospital stay \((2\) days or less, \(3-7\) days, \(8-14\) days, more than 14 days). Draw simple random samples from each group. (b) Obtain lists of patients discharged from all MMH facilities. Number these patients, and then use a random-number table to obtain the sample. (c) Randomly select some MMH facilitics from each of five geographic regions, and then include all the patients on the discharge lists of the selected hospitals. (d) At the beginning of the year, instruct each MMH facility to survey every 500th patient discharged. (e) Instruct each MMH facility to survey 10 discharged patients this week and send in the results.