Very lucid points.

> Well, you can generally assume that even if there are several

variables, given a large enough sample the variations will average

out. None of the variables are going to skew the outcome that much,

and most of them are additive rather than multiplicative. A +/- 1

liter variation (that's a LOT) in shutoff point at fillup from 1/4

tank will only result in a .25 MPG variation. Granted, you will never

get within the sort of precision seen in the science lab, but +/- .5

mpg accuracy  over the long term would not be an unreasonable

assumption.

--
mordo
1990 Carat