GMHS Math Mrs. Becker Website - Home



AP Statistics: Chapter 5.2 PracticeName_____________________________________A family restaurant chain wants to test the market for a new menu item: a grilled chicken sandwich with chipotle salsa. They are interested in both how to market the item and the right price to charge for it. They decide to offer the sandwich at 60 different restaurants in the chain, using two different descriptions on the menu. Half the restaurants’ menus will emphasize “healthy eating” and half will emphasize “value.” These two groups of restaurants will be further divided in three groups, each charging either a High, Medium, or Low price for the sandwich. After a month, they will measure what proportion of customers order the new sandwich.Suppose the company plans to conduct a completely randomized design. List the experimental units, factors, and treatments in this experimental design.Suppose that 30 of the restaurants in the study are free-standing buildings and the other 30 are located inside malls. The company suspects that the different building types may have impact on how people respond to the advertising campaign and the price. How might they alter the design of this experiment to take this into account?A college fitness center offers an exercise program for staff members who choose to participate. The program assesses each participant’s fitness using a treadmill test, and also administers a personality questionnaire. There is a moderately strong positive correlation between fitness score and score for self-confidence. Explain why it would not be possible to conclude from this study that the exercise program increases one’s self-confidence.Agricultural scientists for a chemical company want to determine if a newly developed fertilizer produces heavier tomatoes than the fertilizer they currently manufacture. For their first pilot study, they have 24 healthy young tomato plants growing in individual pots, numbered from 1 to 24.Describe the design of a completely randomized, controlled experiment to test whether the new fertilizer produces heavier tomatoes. Be sure to include the use of a random digits table when assigning subjects to treatments in your explanation.Use the section from the random digits table below to carry out the randomization required by your design and list the outcome of the randomization.27816784161832921337352133774104312685086692555658391007845811206198768715131260084214475377377287447559208563791409245453645668126142147836126091537398481145926683168908407722155847781335867917706928KEY:1a)Experimental units: the 60 restaurantsFactors: menu description and priceTreatments: Healthy-High price, Healthy-Medium price, Healthy-Low price, Value-High price, Value-Medium price, Value-Low price1b)Block for building type: randomly assign the six different treatments to the 30 free-standing buildings, then do the same to the 30 mall restaurants, so that there are exactly five of each building type assigned to each treatment. 2)Since this was an observational study, we cannot establish cause and effect. It is possible, for instance, that people with more self-confidence are more likely to choose to exercise. That is, people’s personality might be a confounding variable.3a)Use a random number table to choose twelve 2-digit numbers from 01 to 24, ignoring repeats. The tomato plants with these numbers will receive the new fertilizer. The remaining 12 plants will act as a control group and will receive the old fertilizer. Measure the total weight of tomatoes produced by each plant, and compare the mean weight in the two groups.3b)The first 12 plant numbers are 16, 18, 13, 21, 04, 08, 10, 07, 11, 20, 15 12. These tomato plants will constitute the treatment group. The remaining 12 plants will be in the control group. ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download