View Full Version : ASM 29.5
09-24-2003, 11:18 PM
The solution states that the mean of fitted Y = the mean of Y. Is that always true? I don't recall seeing that result earlier.
Thanks for your help!
09-25-2003, 12:09 AM
For a model with a constant, the constant is set in such a way as to make this equality true. For example, in the 2 variable model, alpha hat is Y: bar minus beta hat X bar, so the mean of the fitteds (alpha hat plus beta hat times X bar) equals the mean of the actuals (Y bar).
The statement is not generally true for a model without a constant.
09-25-2003, 09:06 AM
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