Scatterplot and Correlation Coefficient

What is the type of association?

• Negative 
• no association
• positive 

What type of association does this graph have?

• positive
• negative
• none
• all of the above

The following scatter plot shows Pam's training as she prepares to run a 6 mile race at the end of the month.  Which of the following would be a reasonable approximation for the length of time it would take for her to run 6 miles? 

• A. 50 min
• B. 80 min
• C. 45 min
• D. 60 min

What type of association does this graph have?

• positive 
• negative
• none
• all of the above

Make a prediction for a resting heart rate after 6 hours of exercise a week.

• 6
• 50
• 55
• 59

Describe the association of the scatter plot

• Linear; positive association
• Linear; negative association
• Non-linear

Estimate the correlation coefficient for this scatterplot.

• A) r = 1.2

• B) r = 0.89

• C)r = 0

• D) r = -0.89

Estimate the correlation coefficient for this scatterplot.

• A) r = -0.9

• B) r = 1

• C) r = 0.9

• D) r = -1

The scatter plot shows the number coffee shops in different cities and the number of violent crimes. Which of the following is NOT true?

• A) As the number of coffee shops increase, violent crimes appears to increase.

• B) The line of best fit (regression line) shows a positive correlation

• C) The data has a positive correlation coefficient

• D) An increase in coffee shops causes an increase in violent crimes

A perfect positive correlation has a correlation coefficient of ____. 

• 1
• -1
• 0