Question

1)________ regression brings one independent variable into the model at a time and does not allow any variables to leave once they have entered.

	Best subsets
	General stepwise
	Backward elimination
	Forward selection

2)The Centers for Disease Control (CDC) would like to test the hypothesis that the proportion of obese adults in the U.S. has increased this year when compared to last year. A random sample of 125 adults this year found that 56 were obese. Last year, a random sample of 140 adults found that 42 were obese. If Population 1 is defined as this year and Population 2 is defined as last year, and using α = 0.01, the critical value for this hypothesis test would be ________.

	1.96
	1.28
	2.05
	2.33

3)

Expedia would like to test the hypothesis that the average roundtrip airfare between Philadelphia and Paris is higher for a flight originating in Philadelphia when compared to a flight originating in Paris. The following data summarizes the sample statistics for roundtrip flights originating in both cities. Assume that the population variances are equal.

	Originating City
	Philadelphia	Paris
Sample mean	$1,240	$1,060
Sample size	15	19
Sample standard deviation	$270	$240

If Population 1 is defined as flights originating in Philadelphia and Population 2 is defined as flights originating in Paris, and using α = 0.05, which one of the following statements is true?

	Because the p-value is greater than α, Expedia cannot conclude that the average roundtrip airfare between Philadelphia and Paris is higher for a flight originating in Philadelphia when compared to a flight originating in Paris.
	Because the p-value is greater than α, Expedia can conclude that the average roundtrip airfare between Philadelphia and Paris is higher for a flight originating in Philadelphia when compared to a flight originating in Paris.
	Because the p-value is less than α, Expedia can conclude that the average roundtrip airfare between Philadelphia and Paris is higher for a flight originating in Philadelphia when compared to a flight originating in Paris.
	Because the p-value is less than α, Expedia cannot conclude that the average roundtrip airfare between Philadelphia and Paris is higher for a flight originating in Philadelphia when compared to a flight originating in Paris.

Answer 1