CORRELATION & REGRESSION:
1) What do you mean by the term correlation?
2) Point out the differences between coefficient of correlation and regression.
3) If the correlation for a given data set is 0.75 what does it signifies.
4) Point out the differences between Karl Pearson and Spearman's Rank correlation
5) Describe the steps used for multiple regression analysis.
PROBABILITY:
1) If a person is vaccinated properly, the probability of getting the disease is .04. Without the vaccination, the probability of getting the disease is .30. Assume 1/4 of the population is properly vaccinated.
a. If a person is selected at random, what is the probability they will get the disease?
b. If a person gets the disease, what is the probability that they were properly vaccinated?
HYPOTHESIS TESTING:
1) In a large population of students, a school claims that the average ACT score is µ = 25. A newspaper disputes this claim and obtains a random sample of 34 students which yields an average of 24.2, and s = 6.2. Conduct a hypothesis test at the 10% level to determine whether there is statistical evidence that the survey is different than the actual population.
2) A test was designed to test student's ability to learn statistics. Thousands took the test and were divided by sex. A random sample of 50 was chosen from each group. The females had an average of 44 with a standard deviation of s = 2.1 and the males had an average of 45 with a standard deviation of s = 2.3. Construct a 95% confidence interval for the difference in mean test scores of the two populations.
3) The following is a random sample of numbers of people who were hired at a company over the last 10 years. Construct a 70% and 90% confidence interval for the difference in male and female hiring.
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Male
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Female
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Hired
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200
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300
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Interviewed
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450
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500
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