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Old 12-24-2005, 09:18 PM
NASAgineer NASAgineer is offline
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Default Re: Prius still Champeen, but HCH-II making push

Quote:
Originally Posted by EricGo
My statistics skills have rusted over time, but the fact that the histogram has reached a normal distribution, and the mean has not changed by more than a few tenths of one mpg over the past 100 cars without a trend argues that the sample size as it currently stands is enough to extrapolate to the whole group.
Just because the GHDB population has stabilized and shows a normal distribution doesn't mean you can extrapolate it to the entire population. There's a good scientific reason why statisticians insist on a random sampling before they can credibly use a sample population to represent the entire population.

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