Pass Attempts Data for pass attempts and yards gained are as follows:
Attempts x | 116 90 82 108 92
Yards y
| 1001 823 851 873 837
Find y ‘ when x = 95.
1. I entered in all of the values for Attempts x into L1, and the y -values into L2 on the TI-83.
To enter values in a list: Press STAT, then 1-for edit, and enter. Move cursor down until
all x- values are entered into L1, and then use the left arrow to move over to L2 to enter in the yvalues.
2. Find values of xy, x2, and y2.
Press STAT, move cursor right to CALC, and 2 for Var Stats and enter; I got the values for my min
x = 82, max X= 116, min Y = 823, max Y = 1001, ∑x = 488, ∑ x2 = 48408, n= 5, ∑y= 4385, ∑ y2 =
3866229, ∑xy = 431256
So the values needed right now are:
∑x = 488
∑y = 4385
∑xy = 431256
∑ x2 = 48408
∑ y2 = 3866229
3. Then find the value of 𝑟.
______ n(∑xy) – (∑x)( ∑y)__________
r = √[n(∑ x2) – (∑x)2] [n(∑ y2) – (∑y)2]
Again, using the TI-83,
I now pressed STAT, and moved the cursor over to CALC.
Then press 8- for LinReg (a + bx) then enter.
I received the following values:
y = a + bx
a = 466.1581109
b = 4.209445585
r2 = .6707628022
r = .8190011002 or after rounding, r = .819
So the equation of the regression line is y ‘ = 466.158 + 4.209x. Therefore, to find y ‘ when x = 95, we
simply plug it in the equation:
y ‘ = a + bx
y ‘ = 466.158 + 4.209(95)
y ‘ = 866.013 yards gained