BSST3083 week problem set 5 2017

FINAL ASSIGNMENT INSTRUCTIONS:

For this homework assignment, you are to select 3 problems to complete.

No two may be of the same type: (a) T test with equal or unequal variance, (b) Paired t test, (c) CHITEST, (d) ANOVA, and (e) Regression. One of your choices must be a regression.

You are to give the Ho and Ha, complete the appropriate test, give the conclusion both in terms of whether to reject the null or not and in terms of how the research question would be answered and mark the cell that points to the conclusion. In each case, assume a 95% confidence level.

When done, delete the extra worksheets and submit.

MOTORS

Four different models of motors are tested for their lifespan under a heavy load. At the end of 100 hours the test is ended. The time to failure (or 100 if no failure) is recorded below. The testers want to determine if there is any difference in the models' lifetimes. If there is a difference, the testers want to know where.

MATH TEST

A mathematics class has taken two tests and the scores for each student are given below. The teacher believes that the first test was easier than the second and wants to test that theory. (Actual data from a real course.)

TAXES AND WORK

Some candidates want to raise taxes and some want to lower them. Higher taxes mean you take home less. Do workers work more hours to compensate? Use the data below from a variety of countries to determine whether a nation's tax rate is associated with its work week. What work week would be expected in a country with a 50% tax rate? How much of the length of the work week explained by taxes? How much change in work week is associated with a 1% increase in the tax rate? Explain why the direction of the relationship does or does not meet your expectation.

(Source: Energy Information Administration, http://www.eia.doe.gov/listserv_signup.html)