Lines of Best Fit, R-Value

Describe the correlation coefficient if

r = 0.90

• Positive, weak

• Positive, strong

• Negative, weak

• Negative, strong

Describe the correlation:

r = -0.98

• Strong positive

• Weak positive

• Strong negative

• Weak negative

If the point with the red x is removed from the scatterplot, what will happen to the slope of the LSRL and the correlation coefficient?

• slope increases, r increases

• slope decreases, r increases

• slope increases, r decreases

• slope decreases, r decreases

• slope is unchanged, r increases

What is the value of the correlation coefficient?

• 0.891

• -0.891

• 0.875

• 0.943

• -0.943

The scatter plot shows the relationship between the number of chapters and the total number of pages for several books. Use the trend line to predict how many pages would be in a book with 6 chapters. 

• ≅100 pages

• ≅170 pages

• ≅60 pages

• ≅20 pages

Which of the following would be the most accurate equation for the scatter plot?

• y = -2x - 7

• y = -x + 7

• y = 3x + 7

• y = 25x + 7

Choose the graph with a trend line that best fits the data.

• graph 1

• graph 2

• graph 3

• graph 4

the slope is -5/7, what does that mean?

• gain 5 hour of sleep for 7 cups of coffee

• lose 5 hours of sleep for 7 cups of coffee

• lose 7 cups of coffee for 5 hours of sleep

• lose 5 cups of coffee for 7 hours of sleep

What would be a good estimate for the regression (r) value?

• −1

• −0.8

• −0.4

• 0.7

What would be a good estimate for the regression (r) value?

• 1

• 0.6

• 0.2

• −0.4