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1. Test for Goodness of Fit. This is where you have a theoretical set of proportions you expect to see in each category.2. Test of Independence. When one population is surveyed and you are testing how two categorical variables influence each other. 3. Test of Homogeneity of Populations. Using di
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1. Chapter 13 Review Which test is appropriate
2. 1. Test for Goodness of Fit. This is where you have a theoretical set of proportions you expect to see in each category.
2. Test of Independence. When one population is surveyed and you are testing how two categorical variables influence each other.
3. Test of Homogeneity of Populations. Using different populations,you want compare different proportions with respect to a categorical variable
3. An experiment in chicken breeding results in offspring having very curly, slightly curly, or normal feathers. If this is the result of a single gene system, then the proportions of offspring in the three phenotypes should be 0.25, 0.45, and 0.30 respectively. In one such experiment, 93 chickens were born. 20 had normal feathers, 50 had slightly curly feathers, and 23 had very curly feathers.
Carry out a test to determine whether the genetic model seems to hold in this setting.
4. In a telephone survey of 800 registered voters, the data are classified both by gender of respondent and by respondents opinion on an environmental bond issue.
Bond Issue
For Against
Men 450 150
Women 160 40
We want to know whether there is good evidence that ones gender influences whether a person is for or against the bond issue.
Use the chi-square test to answer this question. State the hypotheses, discuss conditions, perform calculations, and report your conclusions.
5. The M&M/Mars Company reports that their Peanut M&Ms? Chocolate Candies are produced in the following distribution: 20% each of browns, yellows, reds and blues, and 10% each of greens and oranges. Sam bought a bag of Peanut M&Ms and counted out the following distribution of colors: 12 brown, 7 yellow, 4 red, 8 blue, 13 green and 2 orange.
Perform a test of the companys reported distribution and report your results. Do a complete analysis, that is, include all of the important steps.
6. A study was performed to examine the personal goals of children in grades 4, 5, and 6. A random sample of students was selected from schools in Georgia. The students received a questionnaire regarding achieving personal goals. They were asked what they would most like to do at school: make good grades, be good at sports, or be popular. Results are presented in the table below by the sex of the child.
Boys Girls
Make good grades 96 295
Be popular 32 45
Be good at sports 94 40
Which type of chi-square procedure is appropriate in this setting? Justify your answer.
Carry out the inference procedure you selected. Follow the steps in the Inference Toolbox.
7. Births are not evenly distributed across the days of the week. Fewer babies are born on Saturday and Sunday than on other days, probably because doctors find weekend births inconvenient. A random sample of 700 births from local records shows this distribution across the days of the week:
Day Sun. Mon. Tue. Wed. Thu. Fri. Sat.
Births 84 110 124 104 94 112 72
Perform an appropriate chi-square test.