AP Statistics Estimating Slope

Park rangers are interested in estimating the weight of the bears that inhabit their state. The rangers have data on weight (in pounds) and neck girth (distance around the neck in inches) for 10 randomly selected bears. Here is some computer output from a linear regression analysis of these data. Which of the following represents a 95% confidence interval for the slope of the population least-squares regression line relating the weight of a bear and its neck girth, assuming the conditions for inference are met?

• The slope decreased and the r² increased.
• The slope increased and the r² decreased.
• The slope decreased but r² remained the same.
• Both slope and r² remained the same.

What's the appropriate interpretation of the slope of the regression line?

• For every additional 0.61 hours of growth, the culture is predicted to weight 1 more gram.

• For every additional hour of growth, the culture is predicted to weigh 0.61 more grams.

• For every additional hour of growth, the logarithm of the culture's weight in grams is predicted to increase by 0.61.

• At the beginning of the experiment, the logarithm of the culture's weight in grams was approximately 0.61 ounces.

• A
• B
• C
• D

What is the slope of the line?

• -1

• 1

• -1/2

• -2

• B
• C
• D
• E

• B
• C
• D
• E

• A

• B

• C

• D

• E

• A

• B

• C

• D

• E