Sales: Paint A chain of hardware stores is trying to sell

Statistical Literacy For nonparametric tests, what assumptions, if any, need to be made concerning the distributions of the populations under investigation?

Critical Thinking Suppose you want to test whether there is a difference in means in a matched pair, before-and-after a situation. If you know that the populations under investigation are at least mound-shaped and symmetrical and you have a large sample, is it better to use the parametric paired-differences test or the nonparametric sign test for matched pairs? Explain.

Chemistry: Lubricant In the production of synthetic motor lubricant from coal, a new catalyst has been discovered that seems to affect the viscosity index of the lubricant. In an experiment consisting of 23 production runs, 11 used the new catalyst and 12 did not. After each production run, the viscosity index of the lubricant was determined to be as follows.

Self-Improvement: Memory Professor Adams wrote a book called Improving Your Memory. The professor claims that if you follow the program outlined in the book, your memory will definitely improve. Fifteen people took the professors course, in which the book and its program were used. On the first day of class, everyone took a memory exam; and on the last day, everyone took a similar exam. The paired scores for each person follow. With catalyst 1.6 3.2 2.9 4.4 3.7 2.5 1.1 1.8 3.8 4.2 4.1 Without catalyst 3.9 4.6 1.5 2.2 2.8 3.6 2.4 3.3 1.9 4.0 3.5 3.1 Last exam 225 120 115 275 85 76 114 200 99 135 170 110 216 280 78 First exam 175 110 115 200 60 85 160 190 70 110 140 10 190 200 92 Use a 0.05 level of significance to test the null hypothesis that the scores are the same whether or not people have taken the course against the alternate hypothesis that the scores of people who have taken the course are higher

Sales: Paint A chain of hardware stores is trying to sell more paint by mailing pamphlets describing the paint. In 15 communities containing one of these hardware stores, the paint sales (in dollars) were recorded for the months before and after the ads were sent out. The paired results for each store follow. Using a 0.05 level of significance, test the claim that there is a monotoneincreasing relation between rank in the training program and rank in performance on the job. 8. Cooking School: Chocolate Mousse Two expert French chefs judged chocolate mousse made by students in a Paris cooking school. Each chef ranked the best chocolate mousse as 1. 700 Chapter 12 NONPARAMETRIC STATISTICS With rewards 12 17 15 10 16 20 9 23 8 14 10 No rewards 19 22 11 18 13 25 24 28 21 20 21 Use a 0.01 level of significance to test the null hypothesis that the advert

Dogs: Obedience School An obedience school for dogs experimented with two methods of training. One method involved rewards (food, praise); the other involved no rewards. The dogs were randomly placed into two independent groups of 11 each. The number of sessions required to train each of 22 dogs follows. Use a 0.05 level of significance to test the hypothesis that the number of sessions was the same for the two groups against the alternate hypothesis that the number of sessions was not the same

Training Program: Fast Food At McDouglas Hamburger stands, each employee must undergo a training program before he or she is hired. A group of nine people went through the training program and were hired to work in the Teton Park McDouglas Hamburger stand. Rankings in performance after the training program and after one month on the job are shown (a rank of 1 is for best performance). Use a 0.10 level of significance to test the claim that there is a monotone relation (either way) between ranks given by Chef Pierre and by Chef Andr. 9. Education: TrueFalse Questions Dr. Gill wants to arrange the answers to a truefalse exam in random order. The answers in order of occurrence are shown below. T TTTFTTFFTTTT FFFFFF TTTTTT Test the sequence for randomness using a 0.05. 10. Agriculture: Wheat For the past 16 years, the yields of wheat (in tons) grown on a plot at Rothamsted Experimental Station (England) are shown below. The sequence is by year. 3.8 1.9 0.6 1.7 2.0 3.5 3.0 1.4 2.7 2.3 2.6 2.1 2.4 2.7 1.8 1.9 Use level of significance 5% to test for randomness about the median. Sales after 610 150 790 288 715 465 280 640 500 118 265 365 93 217 280 Sales before 460 216 640 250 685 430 220 470 370 118 117 360 93 291 430 Employee 123456789 Rank, training

Cooking School: Chocolate Mousse Two expert French chefs judged chocolate mousse made by students in a Paris cooking school. Each chef ranked the best chocolate mousse as 1.

Education: TrueFalse Questions Dr. Gill wants to arrange the answers to a truefalse exam in random order. The answers in order of occurrence are shown below. T TTTFTTFFTTTT FFFFFF TTTTTT Test the sequence for randomness using a 0.05.

Agriculture: Wheat For the past 16 years, the yields of wheat (in tons) grown on a plot at Rothamsted Experimental Station (England) are shown below. The sequence is by year. 3.8 1.9 0.6 1.7 2.0 3.5 3.0 1.4 2.7 2.3 2.6 2.1 2.4 2.7 1.8 1.9 Use level of significance 5% to test for randomness about the median.