Linear Regression Model
Click below the x axis to get observations.
After you have a few, click on "show reg" to obtain the regression line.
How would you make a prediction for a new y given an x value ?
Click to obtain more observations.
As you add observations, the regression line changes.
Which is better? The line with fewer observations or with more?
When we make a prediction, what are our sources of error?
We may not have the "right" line !
Even if we have the right line, since the relationship is not exact
there is unpredictable variation about the line.
these issues we need a theoretical model
for how y relates to x.
It has to capture:
A true linear relationship.
An inexact relationship, the points don't fall right on the line.