AnswersCR_AQR_Advanced Quantitative Reasoning A_2111_SAISD 25-26Segmented Bar Graphs

Calculating the Least-Squares Regression Line Answers

10 verified answers1 views
1
Free Preview

In the decathlon event at large track meets, male athletes compete in a total of 10 events. Their combined performance in each of the events is used to determine the winner. Two of the events are the 200-meter dash and the javelin throw. For 12 athletes at a large international competition, performances in these events are recorded and placed in a scatterplot. The performance for one athlete from Latvia is labeled in the graph.

Question illustration
A
This data point weakens the correlation.
B
This data point strengthens the correlation.
C
This data point has no influence on the correlation.
D
Removing this data point would lower the correlation coefficient.
2
Free Preview

Graduation rate is one measure used to compare colleges in national publications. One such publication compared semester tuition against graduation rate, defined as the percentage of students who graduate within four years. The value of r for the scatterplot is 0.856.

Question illustration
A
The correlation would stay the same.
B
The correlation would stay positive and increase.
C
The correlation would stay positive and decrease.
D
The correlation would be negative, rather than positive.
3

To investigate the influence of distracted driving, 13 volunteers were asked to participate in a study involving a driving simulator. The participants drove at a safe speed but were told to stop the car at a random moment during the simulation. The scatterplot shows the reaction time and the simulated car’s stopping distance, in feet, for each volunteer.

Question illustration
A
reaction time 0.5 seconds, stopping distance 35 feet
B
reaction time 1.7 seconds, stopping distance 53 feet
C
reaction time 2 seconds, stopping distance 67 feet
D
reaction time 2.1 seconds, stopping distance 60 feet
4

An official for a regional baseball league examines attendance data for teams in the league. For each team in the league, the number of losses and the average game attendance is shown in the scatterplot. The value of r for the scatterplot is –0.847.

Question illustration
A
2 losses, 11.9 thousand fans
B
2 losses, 15.2 thousand fans
C
5 losses, 10.3 thousand fans
D
9 losses, 7.7 thousand fans
5

A health organization collects data on hospitals in a large metropolitan area. The scatterplot shows the relationship between two variables the organization collected: the number of beds each hospital has available and the average number of days a patient stays in the hospital (mean length of stay).

Question illustration
A
the hospital with 35 beds
B
the hospital with 140 beds
C
the hospital with 200 beds
D
the hospital with 310 beds
6

Car rideshare services are a popular option for people needing to move about in large cities. The scatterplot shows the distances of trips and fares, in dollars, for an adult living in a city over a period of a month. The value of r for the scatterplot is 0.950.

Question illustration
A
The value of the correlation coefficient would be –0.950.
B
The value of the correlation coefficient would not change.
C
The value of the correlation coefficient would be closer to 0.
D
The value of the correlation coefficient would be closer to 1.
7

A nutritionist collects data from 25 popular breakfast cereals. For each cereal, the number of calories per serving is plotted on the x-axis against the number of milligrams of sodium on the y-axis. The value of r for the resulting scatterplot is 0.83. Which of the following is a correct interpretation of this value?

A
Each additional calorie is predicted to add approximately 0.83 mg of sodium.
B
There is a positive relationship between calories and sodium. The relationship is weak.
C
There is a positive relationship between calories and sodium. The relationship is strong.
D
As the number of calories increases, the amount of sodium decreases. The relationship is strong.
8

Graduation rate is one measure used to compare colleges in national publications. One such publication compared semester tuition against graduation rate, defined as the percentage of students who graduate within four years. The value of r for the scatterplot is 0.856.

Question illustration
A
There is no relationship between tuition and graduation rate.
B
Colleges with lower tuition tend to have higher graduation rates.
C
Colleges with higher tuition tend to have higher graduation rates.
D
There is a weak, positive relationship between tuition and graduation rate.
9

An economist studies the relationship between the unemployment rate of adult males and male life expectancy for 12 European countries. The relationship is shown in the scatterplot. The value of r for the scatterplot is –0.423.

Question illustration
A
Unemployment is a cause of lower life expectancy.
B
Countries with higher unemployment rates also have higher life expectancy.
C
Lower unemployment rates may have an association with unhealthy lifestyles, which is also associated with lower life expectancy.
D
Higher unemployment rates may have an association with unhealthy lifestyles, which is also associated with lower life expectancy.
10

An official for a regional baseball league examines attendance data for teams in the league. For each team in the league, the number of losses and the average game attendance are shown in the scatterplot. The value of r for the scatterplot is –0.847.

Question illustration
A
There is no association between losses and attendance.
B
Losses and attendance have a strong, positive association.
C
Losses and attendance have a weak, negative association.
D
Losses and attendance have a strong, negative association.

Did you find these answers helpful?

More from this Course

Quiz
10 verified answers

Segmented Bar Graphs

Quiz
10 verified answers

Describing and Comparing Data with Dotplots and Stemplots

Quiz
10 verified answers

Measures of Center and Location