[tacomax]

Originally Posted by BuddyBear

That link does not even open up. Nice try though....

You need to enroll in How To Click On A Link 101 next semester. Nice try though.

Originally Posted by BuddyBear

Trust me....ANY variable you include will increase the R2. Go try it and tell me if it does not increase. That is a fact....

Adding a variable almost invariably increases R2. It doesn't always increase - I suggest you read the quoted passage from the book. R2 is monotonically increasing - but that doesn't mean it's strictly monotonic.

Since it's your word against someone who wrote a highly regarded book on econometrics, I suggest you take it up with the author and demand he make a correction.

[tacomax]

Originally Posted by durito

It opens up just fine for me. I'd been looking for a good online basic econometrics book. Thanks.

No problems. It's a good little book and isn't so confusing if maths isn't your strong point.

[BuddyBear]

Originally Posted by tacomax

You need to enroll in How To Click On A Link 101 next semester. Nice try though.



Adding a variable almost invariably increases R2. It doesn't always increase - I suggest you read the quoted passage from the book. R2 is monotonically increasing - but that doesn't mean it's strictly monotonic.

Since it's your word against someone who wrote a highly regarded book on econometrics, I suggest you take it up with the author and demand he make a correction.

Sorry, but it ALWAYS increases it. Trust me, i've taken enough stats coures to know at least the basic things of multiple regression

[Ganchrow]

Originally Posted by BuddyBear

Sorry, but it ALWAYS increases it.

The R² is only weakly increasing in the number of model regressors. There do exist pathological cases where the addition of a variable to a regression will have no effect on the coefficient of determination (R²). To wit:

What if the variable being introduced were collinear with an existing variable?

And as corollaries to the above:

What if every observation of the introduced variable were identical and there already existed a constant term?

With or without a constant term, what if the introduced variable were merely a column of 0s?

What if the R² of the regression were already 1?

[tacomax]

I see what you're doing there, Ganch. But BuddyBear has taken lots of stats courses - that seemingly trumps actual statistical theory and pure logic.