Question

The table below gives the completion percentage and interception percentage for five randomly selected NFL quarterbacks. Based on this data, consider the equation of the regression line, yˆ=b0+b1xy^=b0+b1x, for using the completion percentage to predict the interception percentage for an NFL quarterback. Keep in mind, the correlation coefficient may or may not be statistically significant for the data given. Remember, in practice, it would not be appropriate to use the regression line to make a prediction if the correlation coefficient is not statistically significant.

Completion Percentage	60	61	62	65	66
Interception Percentage	5	4.5	4	3.5	1.5

Table

Copy Data

Step 1 of 6 :  

Find the estimated slope. Round your answer to three decimal places.

Answer 1

From given sample data,

X	Y	X * Y	X^2
60	5	300	3600
61	4.5	274.5	3721
62	4	248	3844
65	3.5	227.5	4225
66	1.5	99	4356
314	18.5	1149	19746

Equation of regression line is Ŷ = a + bX          

Where slope = b

b = ( 5 * 1149 - 314 * 18.5 ) / ( 5 * 19746 - ( 314 )2)

= -0.478