Intro Stats
4th Edition
ISBN: 9780321825278
Author: Richard D. De Veaux, Paul F. Velleman, David E. Bock
Publisher: PEARSON
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Textbook Question
Chapter 22, Problem 6E
Bank cards, once more A market researcher working for the bank in Exercise 2 wants to know if the distribution of applications by card is the same for the past three mailings. She takes a random sample of 200 from each mailing and counts the number applying for Silver, Gold, and Platinum. The data follow:
- a) What is the null hypothesis?
- b) What type of test is this?
- c) What are the expected numbers for each cell if the null hypothesis is true?
- d) Find the χ2 statistic.
- e) How many degrees of freedom does it have?
- f) Find the P-value.
- g) What do you conclude?
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Chapter 22 Solutions
Intro Stats
Ch. 22.3 - Why do we need the control group?Ch. 22.3 - Prob. 2JCCh. 22.3 - Prob. 3JCCh. 22.3 - Prob. 4JCCh. 22.3 - Prob. 5JCCh. 22.3 - Prob. 6JCCh. 22.4 - Prob. 7JCCh. 22.4 - Prob. 8JCCh. 22.4 - Prob. 9JCCh. 22 - Human births If there is no seasonal effect on...
Ch. 22 - Bank cards At a major credit card bank, the...Ch. 22 - Prob. 3ECh. 22 - Prob. 4ECh. 22 - Customer ages An analyst at a local bank wonders...Ch. 22 - Bank cards, once more A market researcher working...Ch. 22 - Human births, last time For the data in Exercise...Ch. 22 - Prob. 8ECh. 22 - Prob. 9ECh. 22 - Prob. 10ECh. 22 - Prob. 11ECh. 22 - Prob. 12ECh. 22 - Dice After getting trounced by your little brother...Ch. 22 - MMs As noted in an earlier chapter, Mars Inc. says...Ch. 22 - Nuts A company says its premium mixture of nuts...Ch. 22 - Prob. 16ECh. 22 - NYPD and race Census data for New York City...Ch. 22 - Violence against women In its study When Men...Ch. 22 - Fruit flies Offspring of certain fruit flies may...Ch. 22 - Prob. 20ECh. 22 - Prob. 21ECh. 22 - Lottery numbers The fairness of the South African...Ch. 22 - Prob. 23ECh. 22 - Prob. 24ECh. 22 - Childbirth, part 2 In Exercise 23, the table shows...Ch. 22 - Prob. 26ECh. 22 - Prob. 27ECh. 22 - Prob. 28ECh. 22 - Prob. 29ECh. 22 - Does your doctor know? (part 4) In Exercises 24,...Ch. 22 - Prob. 31ECh. 22 - Prob. 32ECh. 22 - 33. Titanic Here is a table we first saw in...Ch. 22 - NYPD The table below shows the rank attained by...Ch. 22 - Prob. 35ECh. 22 - NYPD again Examine and comment on this table of...Ch. 22 - Cranberry juice Its common folk wisdom that...Ch. 22 - Prob. 38ECh. 22 - Montana A poll conducted by the University of...Ch. 22 - 40. Fish diet Medical researchers followed 6272...Ch. 22 - Prob. 41ECh. 22 - Working parents In April 2009, Gallup published...Ch. 22 - Grades Two different professors teach an...Ch. 22 - Full moon Some people believe that a full moon...Ch. 22 - Grades, again In some situations where the...Ch. 22 - Full moon, next phase In Exercise 44, you found...Ch. 22 - Racial steering A subtle form of racial...Ch. 22 - 48. Titanic, redux Newspaper headlines at the...Ch. 22 - Prob. 49ECh. 22 - Prob. 50ECh. 22 - Prob. 51ECh. 22 - Education by age Use the survey results in the...
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