On 23 Oct 2003 11:16:47 -0700, [EMAIL PROTECTED] (Kevin M. Lausten) wrote: > I am having difficulty understanding how regressions perform. I have > 2 vectors (x = [4, 4, 0], y = [3, 6, 3]) and want to map y to x. When > this is done using a regression formula, I get a = 3 and b = .375. > Now, when I map x to y I get a = 0 and b = 2/3. Why is the second > result not the reflfective inverse of the first?(about the line y = > x)?
You are implying that a correlation of zero, which would be graphed by a flat, horizontal line, should be reflected to make a regression line that goes straight up. The regression slope, each time, is equal to the correlation (r) times the ratio of the standard deviations. As far as there is reflection... you can see that the second is reflected about the line with slope r . -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html "Taxes are the price we pay for civilization." . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
