|HP-10B / HP-10BII error on regression - example|
Message #1 Posted by Gene on 6 Apr 2002, 3:40 p.m.
The HP-10B and HP-10BII give an incorrect answer for the y-intercept on certain regression problems.
Excel and the TI-BAII Plus give the correct answer.
This is a managerial accounting problem. X stands for units produced while Y is for mixed overhead.
Anyway, the HP-10B and HP-10BII give the equation
Y = 510.375 + 0.29166667 X
But Excel and the BAII Plus give
Y = 508.3333 + 0.291666667X
The Y intercept on the 10B is wrong.
Any ideas why? Internal round-off?
I remember problems similar to this on old HPs where people would try to find the mean and std deviation on 999999997 and 9999999995 and 9999999996 and it would zonk out because of hte large numbers involved, but these numbers are not large enough that this should be a problem.