1040/1045 : Exam 2 review

Which of the following are true about scatter plots for R values? Choose all that apply.

• The spread of R=0 would look like a circle

• The spread of R=-1 would be a perfect downward line

• The spread of R=0.7 would be a halfway inflated ball

• I don’t really remember what a R value is

Which of these graphs has an R value of approximately 0.88

• C

• B

• F

• A

Which of the following graphs has a correlation coefficient of around -0.7

• D

• E

• F

• C

Which of the following statements are true about graph F? Choose all that apply.

• Graph F has a correlation coefficient of around -0.67

• Graph F has a strong negative correlation

• Graph F has a correlation coefficient of around -0.88

• Graph F has a weak negative correlation

Which of the following are a true statement? Choose all that apply

• You can almost perfectly predict X from Y in graph A

• The R value for graph B is around -0.8

• The correlation coefficient of graph C is around +0.8

• The R value for graph D is around 0.1, meaning we can closely predict X from Y

Using this scatterplot, estimate the average for Midterm score

• 63

• 78

• 88

• 65

Use this scatterplot to estimate the SD for midterm scores

• SD=10

• SD=82

• SD=20

• SD=5

Using this scatterplot: estimate the average score on the final?

• 28

• 35

• 80

• 51

Using this scatterplot: estimate the SD for final exam scores

• 40

• 10

• 25

• 38

Use funwithstats to calculate the R value for this data set

• R=1

• R=0.8

• R=0.4

• R=0.1