In: Statistics and Probability
Each year, the Chapman University Survey of American Fears asks a random sample of Americans whether they are afraid of various issues. One question on the survey asks about air pollution. The table below reports the number of individuals surveyed in 2018 who responded that they were either afraid or not afraid of air pollution, by political affiliation.
Republican | Independent | Democrat | Total | |
Not afraid of air pollution | 61 | 94 | 28 | 183 |
Afraid of air pollution | 263 | 367 | 376 | 1,006 |
Total | 324 | 461 | 404 | 1,189 |
We’d like to know if, in the American population in 2018, fear of air pollution depends on a person’s political affiliation.
1) Set-up the corresponding null and alternative hypotheses. The appropriate alternativehypothesis is
Group of answer choices
Ha: Republicans are more likely than Democrats to fear air pollution in the US
Ha: There is some association between political affiliation and fear of air pollution in this population
Ha: Republicans and Democrats are not equally likely to fear air pollution in the US
Ha: Democrats are more likely than Republicans to fear air pollution in the US
Ha: Republicans and Democrats are equally likely to fear air pollution in the US
Ha: There is no association between political affiliation and fear of air pollution in this population
2) Which inference procedure should be used?
A - two sample t procedure for two means
B - ANOVA for several means
C - chi-square for two-way tables
D - z procedure for a proportion
E - one sample or matched-pairs t procedure for a mean
F - chi-square for goodness of fit
3) The value of the corresponding test statistic is:
4) What are the conditions for this inference procedure?
A - Normal data AND large enough expected counts.
B - Random selection without repeated measures AND large enough expected counts.
C - Independent random samples AND normal data AND large enough total sample size.
D - Independent random samples AND normal data or large enough total sample size.
E - Independent random samples AND normal data or large enough total sample size AND similar sample standard deviations.
F - One random sample AND normal data AND large enough sample size.
G - One random sample AND normal data or large enough sample size.
H - One random sample AND large enough counts of successes and failures in the sample.
I - Independent random samples AND normal data AND large enough total sample size AND similar sample standard deviations.
J - One random sample AND large enough expected counts.
5) Assuming for now that the conditions for inference are met, conclude in context based on this hypothesis test.
(Be sure to be very specific and to site your computed P-value).
1. Ha: There is some association between political affiliation and fear of air pollution in this population
because we want to check dependency of fear on political affiliation as a whole.
2. C - chi-square for two-way tables
because we will be comparing all the attributes for their independence.
3.
4. The conditions for this inference are :
For chi square test of independence of attributes, the conditions are completely different.
5. Conclusion is shown in 3rd part.
Please rate my answer and comment for doubt.