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Old 12-17-2011, 01:07 PM   #5 (permalink)
Cyborg ECU
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Join Date: Mar 2011
Location: Coastal Southern California
Posts: 6,297

Black and Green - '98 Honda Civic DX Coupe
Team Honda
90 day: 66.42 mpg (US)

Black and Red - '00 Nashbar Custom built eBike
90 day: 3671.43 mpg (US)
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In the comments, here's a response that looks like it could have come from members of

makenakai -

I looked at your test results.

There's only one baseline measurement, so it's really not possible to statistically know the true baseline values, but the ELVIS tests have an average CO% of 0.86 and a standard deviation of 0.25%. This excludes the two measurements with 0.00 CO%, as those should almost certainly be taken as outliers. The baseline CO value is 1.7 standard deviations from the average ELVIS CO measurement.

Given the variation in your data, if you test 50 times you would expect 5 results that are at least 1.7 standard deviations from the mean. Typical statistical significance of a difference between the two conditions - with and without ELVIS - would be assigned if the distance is 1.96 standard deviations or more.

Regarding the hydrocarbons, your baseline is only 0.32 standard deviations from the mean of the ELVIS tests. By all measures, the two conditions can be statistically assumed to be identical.

Do you have more baseline data? That would help firm up the interpretation - it could even help your case.
See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.

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