Week 8 Knowledge Check Homework Practice Questions
Part 1 of 4 - Chi-Square Test for Homogeneity 8.0/ 8.0 Points
Question 1 of 20
1.0/ 1.0
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Students at a high school are asked to evaluate their experience in the class at the end of each school year. The courses are evaluated on a 1-4 scale – with 4 being the best experience possible. In the History Department, the courses typically are evaluated at 10% 1’s, 15% 2’s, 34% 3’s, and 41% 4’s.
Mr. Goodman sets a goal to outscore these numbers. At the end of the year he takes a random sample of his evaluations and finds 10 1’s, 13 2’s, 48 3’s, and 52 4’s. At the 0.05 level of significance, can Mr. Goodman claim that his evaluations are significantly different than the History Department’s?
Enter the test statistic - round to 4 decimal places.
Test statistic= 3.0021
Answer Key: 3.0021
Feedback:
1's 2's 3's 4's
Observed Counts 10 13 48 52
Expected Counts 123 *.10 = 12.3 123*.15 = 18.45 123*.34 = 41.82 123*.41 = 50.43
Test Stat =
Question 2 of 20
1.0/ 1.0 Points
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A company manager believes that a person’s ability to be a leader is directly correlated to their zodiac sign. He never selects someone to chair a committee without first evaluating their zodiac sign. An irate employee sets out to prove her manager wrong. She claims that if zodiac sign truly makes a difference in leadership, then a random sample of 210 CEO’s in our country would reveal a difference in zodiac sign distribution. She finds the following zodiac signs for her random sample of 210 CEO’s:
Births Signs
25 Aries
13 Taurus
17 Gemini
21 Cancer
16 Leo
18 Virgo
15 Libra
16 Scorpio
20 Sagittarius
11 Capricorn
23 Aquarius
15 Pisces
Can she conclude that zodiac sign makes a difference in whether or not a person makes a good leader?
Enter the p-value - round to 4 decimal places. Make sure you put the 0 in front of the decimal.
p-value = 0.4798
Answer Key: 0.4798
Feedback:
The Expected Count is all the same value. 210*(1/12) = 17.5
Births Signs Expected Count
25 Aries 17.5
13 Taurus 17.5
17 Gemini 17.5
21 Cancer 17.5
16 Leo 17.5
18 Virgo 17.5
15 Libra 17.5
16 Scorpio 17.5
20 Sagittarius 17.5
11 Capricorn 17.5
23 Aquarius 17.5
15 Pisces 17.5
Use Excel to find the p-value
=CHISQ.TEST(Highlight Observed, Highlight Expected)
Question 3 of 20
1.0/ 1.0 Points
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An urban economist is curious if the distribution in where Oregon residents live is different today than it was in 1990. She observes that today there are approximately 3,109 thousand residents in NW Oregon, 902 thousand residents in SW Oregon, 244 thousand in Central Oregon, and 102 thousand in Eastern Oregon. She knows that in 1990 the breakdown was as follows: 72.7% NW Oregon, 20.7% SW Oregon, 4.8% Central Oregon, and 2.8% Eastern Oregon.
Can she conclude that the distribution in residence is different today at a 0.05 level of significance?
Enter the test statistic - round to 4 decimal places.
Test statistic= 10.1714
Answer Key: 10.1714
Feedback:
NW Oregon SW Oregon Central Oregon Eastern Oregon
Observed Counts 3109 902 244 102
Expected Counts 4357*.727 = 3167.539 4357*.207= 901.899 4357*.048= 209.136 4357*.028= 121.996
Test Stat = [Show Less]