Quote:
Originally Posted by pasadena_commut
An interesting, but not convincing, set of observations....
1. The data is limited. The means differ by .37 mpg but that is not much different than the variation within the measurements, so we can't say with much confidence yet if it the measured difference is statistically significant.
|
I didn't have time to compute whether or not it is statistically significant yet. Given the trajectory, a few more samples would easily make the difference.
Quote:
|
2. You knew the state of the car for each test, which opens up the possibility of subconscious changes in driving style which could bias the results. If you do repeat the experiment it would be good if you could have somebody else flip a coin before each run and then open or close holes without telling you which they did. You can determine which it was at the end of the run.
|
Blind studies are not reasonable in this situation. In fact, if you only trust blind studies, all posts on this forum are useless to you. This information is made public for others to think about, test for themselves, and possibly design better and safer solutions. I will be doing that myself, too.
Quote:
|
I'm still skeptical - it doesn't seem right that the tiny amount of air coming out of those two small holes could significantly affect the large and continuously generated volume of low pressure air behind the car.
|
Although my background is in experimental psychology, I spend my free time messing with tangential bypass vacuums. I know from experience that a small leak in the system affects waterlift in ways that seem disproportionate. I'm used to dealing with enclosed systems where air dynamics don't play much of a role in a system that is designed for larger volumes of air than are actually used, so I didn't exactly know what to expect in this situation. The results of this test, then, are in line with my experiences with enclosed systems involving waterlift.