Answers SC-Statistical Modeling SDPCCorrelation

Correlation Answers

2 verified answers

Free Preview

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.

reaction time 0.5 seconds, stopping distance 35 feet

reaction time 1.7 seconds, stopping distance 53 feet

reaction time 2 seconds, stopping distance 67 feet

reaction time 2.1 seconds, stopping distance 60 feet

Free Preview

A scatterplot shows the relationship between semester tuition and 4-year graduation rate for several colleges. The graph shows that as tuition increases, graduation rates also tend to increase.

Higher tuition causes students to graduate at higher rates.

Graduation rate causes tuition to increase at colleges.

There is no relationship between tuition and graduation rate.

There is a positive association between tuition and graduation rate, but this does not mean one causes the other.

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.

The correlation would stay the same.

The correlation would stay positive and increase.

The correlation would stay positive and decrease.

The correlation would be negative, rather than positive.

There is no relationship between tuition and graduation rate.

Colleges with lower tuition tend to have higher graduation rates.

Colleges with higher tuition tend to have higher graduation rates.

There is a weak, positive relationship between tuition and graduation rate.

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.

This data point weakens the correlation.

This data point strengthens the correlation.

This data point has no influence on the correlation.

Removing this data point would lower the correlation coefficient.

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

point A

point B

point C

point D

An entertainment reporter examines the average ticket prices of Broadway shows, comparing them to the number of total performances the shows have had. A resulting scatterplot shows a strong, positive relationship. The value of r for the scatterplot is 0.763. Which statement best explains the relationship between the variables?

Lower ticket prices cause fewer performances to be offered.

Higher ticket prices cause more performances to be offered.

Less popular shows have higher ticket prices and offer fewer performances.

More popular shows have higher ticket prices and offer more performances.

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.

There is no association between losses and attendance.

Losses and attendance have a strong, positive association.

Losses and attendance have a weak, negative association.

Losses and attendance have a strong, negative association.

One statistic used to measure a country’s wealth is its gross domestic product (GDP). A higher GDP indicates greater wealth in the country. A researcher compared the GDP per person for 12 countries with the life expectancy of that country. The data for the 12 countries are shown in the scatterplot. The value of r for the scatterplot is 0.608.

There is little relationship between GDP and life expectancy.

Countries with lower GDPs tend to have higher life expectancies.

Countries with higher GDPs tend to have lower life expectancies.

Countries with higher GDPs tend to have higher life expectancies.

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?

Each additional calorie is predicted to add approximately 0.83 mg of sodium.

There is a positive relationship between calories and sodium. The relationship is weak.

There is a positive relationship between calories and sodium. The relationship is strong.

As the number of calories increases, the amount of sodium decreases. The relationship is strong.

Did you find these answers helpful?

Correlation Answers

More from this Course

TRY EDGENUITY HACKS