Understanding Basic Statistics
8th Edition
ISBN: 9781337672320
Author: BRASE
Publisher: Cengage
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Textbook Question
Chapter 11, Problem 9CR
Before you solve Problems 6-10, first classify the problem as one of the following:
Chi-square test of independence or homogeneity
Chi-square goodness of fit
Chi-square for testing
Then in each of the problems when a test is to be performed do the following:
(i) Give the value of the level of significance. State the null and alternate hypotheses.
(ii) Find the sample test statistic.
(iii) Find or estimate the P-value of the sample test statistic.
(iv) Conclude the test.
(v) Interpret the conclusion in the context of the application.
Teacher Ratings: Grades Professor Stone complains that student teacher ratings depend on the grade the student receives. In other words, according to Professor Stone, a teacher who gives good grades gets good ratings, and a teacher who goes had grades gets had ratings. To test this claim, the Student Assembly took a random sample of 300 teacher ratings on which the student's grade fur the course also was indicated. The results are given in the following table. Test the hypothesis that teacher ratings and student grades are independent at the 0.01 level of significance.
| Rating | A | B | c | f (or withdrawal) | Row Total |
| Excellent | 14 | 18 | 15 | 3 | 50 |
| Average | 25 | 35 | 75 | 15 | 150 |
| Poof | 21 | 27 | 40 | 12 | 100 |
| Column Total |
60 | 80 | 110 | 30 | 300 |
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Question 4
An article in Quality Progress (May 2011, pp. 42-48) describes the use of factorial experiments to improve a
silver powder production process. This product is used in conductive pastes to manufacture a wide variety of
products ranging from silicon wafers to elastic membrane switches. Powder density (g/cm²) and surface area
(cm/g) are the two critical characteristics of this product. The experiments involved three factors: reaction
temperature, ammonium percentage, stirring rate. Each of these factors had two levels, and the design was
replicated twice. The design is shown in Table 3.
A222222222222233
Stir Rate
(RPM)
Ammonium
(%)
Table 3: Silver Powder Experiment from Exercise 13.23
Temperature
(°C)
Density
Surface Area
100
8
14.68
0.40
100
8
15.18
0.43
30
100
8
15.12
0.42
30
100
17.48
0.41
150
7.54
0.69
150
8
6.66
0.67
30
150
8
12.46
0.52
30
150
8
12.62
0.36
100
40
10.95
0.58
100
40
17.68
0.43
30
100
40
12.65
0.57
30
100
40
15.96
0.54
150
40
8.03
0.68
150
40
8.84
0.75
30
150…
Chapter 11 Solutions
Understanding Basic Statistics
Ch. 11.1 - Statistical Literacy In general, are chi-square...Ch. 11.1 - Statistical Literacy For chi-square distributions,...Ch. 11.1 - Statistical Literacy For chi-square tests of...Ch. 11.1 - Critical thinking In general, how do the...Ch. 11.1 - Critical Thinking Zane is interested in the...Ch. 11.1 - Critical Thinking Charlotte is doing a study on...Ch. 11.1 - Interpretation: Test of Homogeneity Consider...Ch. 11.1 - Interpretation: Test of Independence Consider...Ch. 11.1 - For Problems 9-19. please provide the following...Ch. 11.1 - For Problems 9-19, please provide the following...
Ch. 11.1 - For Problems 9-19, please provide the following...Ch. 11.1 - For Problems 9-19. please provide the following...Ch. 11.1 - For Problems 9-19. please provide the following...Ch. 11.1 - For Problems 9-19. please provide the following...Ch. 11.1 - For Problems 9-19. please provide the following...Ch. 11.1 - For Problems 9-19. please provide the following...Ch. 11.1 - Prob. 17PCh. 11.1 - Prob. 18PCh. 11.1 - Prob. 19PCh. 11.2 - Statistical Literacy For a chi-square...Ch. 11.2 - Statistical Literacy How are expected frequencies...Ch. 11.2 - Statistical Literacy Explain why goodness-of-fit...Ch. 11.2 - Critical Thinking When the sample evidence is...Ch. 11.2 - For Problems 5-14, please provide the following...Ch. 11.2 - For Problems 5-14, please provide the following...Ch. 11.2 - For Problems 5-14, please provide the following...Ch. 11.2 - For Problems 5-14, please provide the following...Ch. 11.2 - For Problems 5-14, please provide the following...Ch. 11.2 - Prob. 10PCh. 11.2 - Prob. 11PCh. 11.2 - For Problems 5-14, please provide the following...Ch. 11.2 - Prob. 13PCh. 11.2 - Prob. 14PCh. 11.2 - Prob. 15PCh. 11.2 - For Problems 5-14, please provide the following...Ch. 11.3 - Statistical Literacy Docs the x distribution need...Ch. 11.3 - Prob. 2PCh. 11.3 - Prob. 3PCh. 11.3 - For Problems 3-11, please provide the following...Ch. 11.3 - For Problems 3-11. please provide the following...Ch. 11.3 - For Problems 3-11. please provide the following...Ch. 11.3 - Prob. 7PCh. 11.3 - For Problems 3-11, please provide the following...Ch. 11.3 - For Problems 3-11. please provide the following...Ch. 11.3 - Prob. 10PCh. 11.3 - Prob. 11PCh. 11.4 - Prob. 1PCh. 11.4 - Statistical Literacy What is the symbol used for...Ch. 11.4 - Prob. 3PCh. 11.4 - Statistical Literacy How does the t value for the...Ch. 11.4 - Prob. 5PCh. 11.4 - Using Computer Printouts Problems 5 and 6 use the...Ch. 11.4 - In Problems 7-12, parts (a) and (b) relate to...Ch. 11.4 - In Problems 7-12, parts (a) and (b) relate to...Ch. 11.4 - In Problems 7-12, parts (a) and (b) relate to...Ch. 11.4 - In Problems 7-12, parts (a) and (b) relate to...Ch. 11.4 - Prob. 11PCh. 11.4 - Prob. 12PCh. 11.4 - Prob. 13PCh. 11.4 - Prob. 14PCh. 11.4 - Prob. 15PCh. 11.4 - Prob. 16PCh. 11.4 - Prob. 17PCh. 11.4 - Prob. 18PCh. 11.4 - Prob. 19PCh. 11 - Terminology Match each of the following tests to...Ch. 11 - Prob. 2CRCh. 11 - Statistical Literacy of the following random...Ch. 11 - Prob. 4CRCh. 11 - Prob. 5CRCh. 11 - Before you solve Problems 6-10, first classify the...Ch. 11 - Prob. 7CRCh. 11 - Before you solve Problems 6-10, first classify the...Ch. 11 - Before you solve Problems 6-10, first classify the...Ch. 11 - Prob. 10CRCh. 11 - Prob. 11CRCh. 11 - Prob. 12CRCh. 11 - Prob. 13CRCh. 11 - Prob. 14CRCh. 11 - Prob. 15CRCh. 11 - The Statistical Abstract of the United States...Ch. 11 - Prob. 1LCWPCh. 11 - Prob. 2LCWPCh. 11 - Prob. 3LCWPCh. 11 - Prob. 4LCWPCh. 11 - Prob. 1CRPCh. 11 - Prob. 2CRPCh. 11 - Prob. 3CRPCh. 11 - Prob. 4CRPCh. 11 - Prob. 5CRPCh. 11 - Prob. 6CRPCh. 11 - Prob. 7CRP
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