The number of minutes on the phone and the customer satisfaction rating have a weak, negative relationship.

Explain what it means to have a weak, negative relationship in this context.

Elena collects data to investigate the relationship between the number of bananas she buys at the store, , and the total cost of the bananas, . Which value for the correlation coefficient is most likely to match a line of best fit of the form for this situation?

A researcher creates a scatter plot that displays the relationship between the number of years in business, , and the percentage of company business that is fair trade, . The researcher creates a line of best fit, , and wants to find the residuals for the companies that have been in business for 3 years. 

1. Find the residuals for the two points representing companies that have been in business for 3 years,  and .
2. Compare the residuals for the two companies that have been in business for 3 years. How are they different? How are they similar? What does the information about the residuals for the two companies tell you about how much of their business that is fair trade?

The correlation coefficient, , is given for several different data sets. Which value for indicates the weakest correlation?

Which of the following is the best estimate of the correlation coefficient for the data represented by the scatter plot?

Graph of a scatter plot, xy-plane, origin O. Horizontal axis scale 0 to 50, by 10’s. Vertical axis scale 0 to 100, by 20’s. Best fit line from approximately (8 comma 78) to near (45 comma 45). The data is slightly scattered and trends downward with a negative slope.