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# Problem 2

11.1 Creating the Least Squares Equation

The following set of data is randomly selected from a STA 2122 class of mine from spring 2010. The list includes clicker points earned in class (clickers allow students to answer questions in class and to have their answers scored) and their final averages. Use the data to find the least squares prediction line:

Clicker points 32 11 34 41 16 15 7 15

Class Average 99 70 91 101 79 72 68 68

I plugged an entire class of 200 into SPSS in order to calculate the least squares line for the entire data set. The results were as follows: y = 0.512X + 70.196

What does x = 0 represent here?

What is the expected grade for students who do not earn any clicker points?

What is the average grade for a student who has 20 clicker points?