Multiple Regression R^2 Issue

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Guest

Whenever I run a multiple regression it always tells me that my R^2 is 1
Now I know these numbers aren't that good.
Maybe someone can help me figure this out.
Here is what it outputs in the summary field:
Regression Statistics:
Multiple R: 1
R Square: 1
Adj. R Square: -1.2E-09
Standard Error: 1.15E-10
Observations 3

I have 7 input variables each with 3 observations.
Anyone know what is going on or if I am just screwing it up and reading it
wrong?
I haven't been in stat for a while, and when I was I used SPSS which was way
more user friendly.
Thanks.

I know there are very ef
 
I am not sure what you were intending to do, but you appear to have asked
Excel to fit 3 variables (or 2 variables and an intercept) to 3 data points,
which by definition will fit perfectly (though is unlikely to be meaningful).

Jerry
 
That makes sense. So in order to have it not = 1 I need to add more data
points for each variable, correct?
 
However, when I run a single regression on just one variable's data, even
though it is only 3 data entries, it gives me a R^2 anywhere from .08 to .98
which would make sense to me. Why when I add multiple variables would it
then change to being 1 when it seemingly works for single variable?
 
When your model has as many free parameters as data points, then there are
zero degrees of freedom for lack of fit. The fit will be perfect and R^2
will be one.

Jerry
 
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