Regression Quiz

1. State the 2 inferences drawn when using regression data. slope, intercept
2. State the assumptions for regression inference.

• for any x value, y-data is normally  distributed.
• for any x value, the y-data's standard deviation is the same.
• the means of the y-data distribution at any value of x form a straight line relationship:

3. Fill ou the table shown below and use it to calculate the standard error (s) of the least squares regression line.

s = [ S(y - ŷ)² / (n-2) ]^1/2               ŷ = 2.05x - 0.067      s = 0.286

	Data Points			Total
X	1	2	3
Y	2.1	3.8	6.2
ŷ	1.983	4.033	6.083
(y - ŷ)	0.177	-0.233	0.177
(y - ŷ)2	0.0137	0.0543	0.0137	0.0817