Thread: hybrid plateau
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Old 06-04-2010, 05:55 PM   #17 (permalink)
bwilson4web
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17 i3-REx - '14 BMW i3-REx
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Quote:
Originally Posted by MechanicalRandall View Post
I think I understand the point of the graph, just not the actual arrangement of the data. I understand that you shifted the curves, but what actually makes these curves? How is the data arranged along the x-axis and what are the two colored rectangles for?

Sorry if I'm looking too far into this.
Once I have the MPG data for each vehicle, I sort them individually so they are in order from lowest to highest.

I add an index column from 1 to 200. Then I shift each vehicle so the middle of their values corresponds to 100. Call it the median, which it is. So the medians of each vehicle cross at 100. Then I plot all vehicles.

Now the two rectangles highlight:
  • linear range - those that appear to fall on a line
  • exponential - the extreme mileage cases that fall outside of 'normal.'
Those are not strict math definitions but 'eyeballed' to make sense.

Bob Wilson
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2019 Tesla Model 3 Std. Range Plus - 215 mi EV
2017 BMW i3-REx - 106 mi EV, 88 mi mid-grade
Retired engineer, Huntsville, AL
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