Question

In what follows use any of the following tests/procedures: Regression, multiple regression, confidence intervals, one sided T-test or two sided T-test. All the procedures should be done with 5% P-value or 95% confidence interval. Open Cars 04 data. Setup: Is it reasonable to say that cars with 8 cylinders have highway gas mileage (MPG) lower than the cars with 6 cylinders?

1. What test/procedure did you perform?
A. One sided T-test
B. Two sided T-test
C. Regression
D. Confidence interval
2. Statistical interpretation?
A. Since P-value is small we are confident that the slope is not zero.
B. Since P-value is small we are confident that the averages are different.
C. Since P-value is too large the test is inconclusive.
D. None of these.
3. Conclusion?
A. Yes, this is a reasonable belief.
B. No, we cannot confirm that this is a reasonable belief.

Answer 1

1) B

2) B

3) A

Explanation:

1) For comparing two samples, two sided t-test is used

2) if two sided t-test is used then we compare mean of the two samples and not slope

3) We accept an confirm the hypothesis as reasonable belief or reject/confirm the hypothesis as not a reasonable belief. We do not reject a hypothesis if we can't confirm whether it is a resonable belief.