Differences between revisions 1 and 2
Revision 1 as of 2023-10-28 05:18:15
Size: 1390
Comment:
Revision 2 as of 2023-10-28 05:37:22
Size: 1293
Comment:
Deletions are marked like this. Additions are marked like this.
Line 1: Line 1:
= Linear Regression = = Ordinary Least Squares =
Line 3: Line 3:
A linear regression expresses the linear relation of a treatment variable to an outcome variable. '''Ordinary Least Squares''' ('''OLS''') is a linear regression method. It minimizes root mean square errors.
Line 11: Line 11:
== Regression Line ==

A regression line can be especially useful on a scatter plot.
== Univariate ==
Line 22: Line 20:

----



== Regression Computation ==

Ordinary Least Squares

Ordinary Least Squares (OLS) is a linear regression method. It minimizes root mean square errors.


Univariate

The regression line passes through two points:

[ATTACH]

and

[ATTACH]

Take the generic equation form of a line:

[ATTACH]

Insert the first point into this form.

[ATTACH]

This can be trivially rewritten to solve for a in terms of b:

[ATTACH]

Insert the second point into the original form.

[ATTACH]

Now additionally insert the solution for a in terms of b.

[ATTACH]

Expand all terms to produce:

[ATTACH]

This can now be eliminated into:

[ATTACH]

Giving a solution for b:

[ATTACH]

This solution is trivially rewritten as:

[ATTACH]

Expand the formula for correlation as:

[ATTACH]

This can now be eliminated into:

[ATTACH]

Finally, b can be eloquently written as:

[ATTACH]

Giving a generic formula for the regression line:

[ATTACH]


CategoryRicottone

Statistics/OrdinaryLeastSquares (last edited 2025-01-10 14:33:38 by DominicRicottone)