Data Analysis Regression Equation

[Jason S]

I need to know the equation behind the Data Analysis Tools
Add-in Regression Equation.

Does anyone know what the underlying equation is?

 

[Harlan Grove]

I need to know the equation behind the Data Analysis Tools
Add-in Regression Equation.

Does anyone know what the underlying equation is?

Before Excel 2003, it comes straight out of standard stats textbooks (which was
a problem). Beginning with Excel 2003, it uses a better numerical algorithm, but
this means a single formula would no longer truly describe it.

 

[Jason S]

for Excel 2000, is it just a simple OLS regression? Is
this also true for 2000 add-ins, or do newer add-ins for
2000 use newer algorithms?

Jason

 

[Harlan Grove]

for Excel 2000, is it just a simple OLS regression? Is
this also true for 2000 add-ins, or do newer add-ins for
2000 use newer algorithms?

...

Yes, for XL2K it's simple OLS.

Which add-ins do you mean? If you mean the Data Analysis ToolPak, I believe it
uses Excel's LINEST.

 

[Jerry W. Lewis]

It is OLS in all versions. Prior to 2003, It formed the normal
equations and then inverted X'X ... Numerically, if you form X'X, you
have already lost the battle with ill-conditioned problems (finite
precision problems associated with squaring/summing large numbers).
Excel 2003 decomposes X, so that the solution to the normal equations
can be calculated without ever calculating the normal equations themselves.

Jerry

for Excel 2000, is it just a simple OLS regression? Is
this also true for 2000 add-ins, or do newer add-ins for
2000 use newer algorithms?

Jason

-----Original Message-----
...
Tools

Before Excel 2003, it comes straight out of standard

stats textbooks (which was

a problem). Beginning with Excel 2003, it uses a better

numerical algorithm, but

this means a single formula would no longer truly

describe it.