11. Correlation

Given the following correlation coefficients, which value of $r$ would most likely correspond to a scatterplot showing a strong negative linear relationship between two variables?

Which of the following best describes a scatterplot and its primary use in statistics?

Which of the following scatterplots best represents a negative correlation between two variables?

Which of the following scatterplots best illustrates a correlation that is affected by $non-linearity$?

Writing Use an appropriate research source to find a real-life data set with the indicated cause-and-effect relationship. Write a paragraph describing each variable and explain why you think the variables have the indicated cause-and-effect relationship.

a. Direct Cause-and-Effect: Changes in one variable cause changes in the other variable.

What does it mean to say two variables are positively associated? Negatively associated?

"In Exercises 19-22, two variables are given that have been shown to have correlation but no cause-and-effect relationship. Describe at least one possible reason for the correlation.

20. Alcohol use and tobacco use"

For the scatter diagram shown, which of the following best describes the relationship between the two variables if the points form a pattern that rises from left to right?