Quarq Accuracy

I've ridden one stretch of road enough to try to see how repeatable the Quarq CinQo is. It's the stretch from the bottom of Montebello to the school. So, we can play some games with numbers. Let's assume that I didn't change wheels (I probably put a set on that weighs ~1/2 lb lighter for some runs) and that my body weight and clothes were constant. Here are the results:

time	average power	deviation	kJ
00:14:09	284	101.91%	241.1
00:15:39	250	100.24%	234.8
00:12:28	326	101.78%	243.8
00:12:39	314	99.83%	238.3
00:13:33	286	98.21%	232.5
00:13:03	302	99.40%	236.5
00:12:37	311	98.70%	235.4

So, the mean is 237.5 kJ, and I've tabulated the deviation from this. It looks like the Quarq is well within its +/-2% accuracy spec, but of course, this spans a lot of time and probably many variations in weight and equipment. Oh yeah, I'm neglecting the confidence in the mean and such things that probably matter. I'm basically impressed that a device as rugged as this can give such repeatable data day after day.

OK, enough geeking out for a day.