One recent study found that online math and statistics training quizzes worked quite well. The regression equation,

y

=

91.169

3.1559

x

y^=91.169-3.1559x

, expresses statistical dependence of the final grade in statistics (

y

y^

) on the number of quizzes missed by students (x

x

) in a sample of 16 statistics students. If the coefficient of determination isr

2

=

0.8805

r2=0.8805

, then the coefficient of correlation is

• 0.966
• -0.966
• 0.775
• 0.775
• 0.938
• 0.938
• 0.927
• -0.927
• 0.8805
• -0.8805
• 0.902
• -0.902
• 0.938
• -0.938
• 0.972
• -0.972
• None of the above.