Chapter 3 Multiple Choice

Here is data on the total number of hours of delay per year at 10 major highway intersections in the western United States versus traffic volume (measured by average number of vehicles per day that pass through the intersection). Which is the explanatory variable?

• average vehicles per day

• number of hours of delay per year

• major highway intersections

• traffic

Tags

CCSS.HSS.ID.C.9

Here is data on the total number of hours of delay per year at 10 major highway intersections in the western United States versus traffic volume (measured by average number of vehicles per day that pass through the intersection). How would you describe the association?

• Very weak, negative, linear association between the average vehicles per day and the hours of delay per year.

• Positive, negative, curved association between the average vehicles per day and the hours of delay per year.

• Somewhat strong, positive, linear relationship between the average vehicles per day and the hours of delay per year.

• No relationship

Tags

CCSS.6.SP.B.5C

CCSS.HSS.ID.A.3

In a statistics course, a linear regression equation was computed to predict the final-exam score from the score on the first test. The equation was yhat = 10 + 0.9x where yhat is the predicted final exam score and x is the score on the first test.

Carla scored 95 on the first test. What is the predicted value of her score on the final exam?

• 85.5

• 90

• 95

• 95.5

In a statistics course, a linear regression equation was computed to predict the final-exam score from the score on the first test. The equation was yhat = 10 + 0.9x where yhat is the predicted final exam score and x is the score on the first test.

Bill scored a 90 on the first test and a 93 on the final exam. What is the value of his residual?

• -2

• 2

• 3

• 93

Tags

CCSS.HSS.ID.B.6B

1.      The correlation between the heights of fathers and the heights of their (fully grown) sons is r = 0.52. This value was based on both variables being measured in inches. If fathers' heights were measured in feet (one foot equals 12 inches), and sons' heights were measured in furlongs (one furlong equals 7920 inches), the correlation between heights of fathers and heights of sons would be

• much smaller than 0.52

• slightly smaller than 0.52

• unchanged: equal to 0.52

• slightly larger than 0.52

A least-squares regression line for predicting weights of basketball players on the basis of their heights produced the residual plot below. What does the residual plot tell you about the linear model?

• A residual plot is not an appropriate means for evaluating a linear model.

• The curved pattern in the residual plot suggests that there is no association between the weight and height of basketball players.

• The curved pattern in the residual plot suggests that the linear model is not appropriate.

• There are not enough data points to draw any conclusions from the residual plot.

Tags

CCSS.HSS.ID.B.6B

Use the following to answer questions 7 - 10. One concern about the depletion of the ozone layer is that the increase in ultraviolet (UV) light will decrease crop yields. An experiment was conducted in a green house where soybean plants were exposed to varying levels of UV, measured in Dobson units. At the end of the experiment the yield (kg) was measured. A regression analysis was performed with the following results:

• 
• 
• 
• 

Tags

CCSS.8.SP.A.3

Use the following to answer questions 7 - 10. One concern about the depletion of the ozone layer is that the increase in ultraviolet (UV) light will decrease crop yields. An experiment was conducted in a green house where soybean plants were exposed to varying levels of UV, measured in Dobson units. At the end of the experiment the yield (kg) was measured. A regression analysis was performed with the following results:\

Which of the following is correct interpretation of the slope?

• If the UV value increases by 1 Dobson unit, the yield is expected to increase by 0.0463 kg.

• UV is expected to decrease by 0.0463 Dobson units for each additional increase in kg of soybeans

• Soybean yield is expected to decrease by 0.0463 kg for each additional increase in Dobson unit of UV.

• The predicted yield is 4.3 kg when the UV value is 20 Dobson units.

Tags

CCSS.8.SP.A.3

Use the following to answer questions 7 - 10. One concern about the depletion of the ozone layer is that the increase in ultraviolet (UV) light will decrease crop yields. An experiment was conducted in a green house where soybean plants were exposed to varying levels of UV, measured in Dobson units. At the end of the experiment the yield (kg) was measured. A regression analysis was performed with the following results:\

Which of the following is correct interpretation of the y-intercept?

• When the crop yield is 0, we expect the UV to be 3.9800118 Dobsons.

• When the UV is 0, we expect the crop yield to decrease 0.046285 kg.

• When the UV is 0 Dobsons, we expect the corn yield to be 3.9800118 kg.

• The predicted yield is 4.3 kg when the UV value is 20 Dobson units.

Tags

CCSS.8.SP.A.3

Use the following to answer questions 7 - 10. One concern about the depletion of the ozone layer is that the increase in ultraviolet (UV) light will decrease crop yields. An experiment was conducted in a green house where soybean plants were exposed to varying levels of UV, measured in Dobson units. At the end of the experiment the yield (kg) was measured. A regression analysis was performed with the following results:\

Predict the crop yield when soybeans are exposed to a UV of 20 Dobsons.

• 0.593 kg

• 3.054 kg

• 4.906 kg

• -5.645 kg

Tags

CCSS.HSS.ID.B.6A