Correlation and R Value Review

Correlation coefficient is represented by "R".

• True

• False

The correlation coefficient is a number "r" such that:

• -1 < r < 1

• -1 > r > 1

• -1 ≤ r ≤ 1

• -1 ≥ r ≤ 1

If every brother is exactly two inches taller than his sister, what would the correlation between the heights of brothers and sisters be?

• Nearly 1

• 0

• Somewhat positive

• 1

Correlation applies to both quantitative and categorical data.

• True

• False

Which of the following is true for correlation coefficients?

• x is the explanatory variable and y is the response variable.

• x is the response variable and y is the explanatory variable.

• The choice of x and y as the explanatory and response variables does not matter.

Estimate the correlation coefficient

• r = 1

• r = -1

• r ≈ -0.8

• r ≈ 0.8

• r ≈ -0.5

Estimate the correlation coefficient for this scatterplot.

• A) r = 1.2

• B) r = 0.89

• C)r = 0

• D) r = -0.89

Which graph represents data that has a correlation coefficient close to -1?

• 
• 
• 
• 

What type of association does this scatter plot represent?

• Positive linear association

• Negative linear association

• No association

• Nonlinear association

Which value is the closest to the correlation coefficient for the data?

• -0.07

• -0.73

• 0.07

• .73