Inspired by the sleep talk, I downloaded my Jawbone Up data and tried to replicate the speaker's finding that deep sleep % is correlated to previous night's sleep duration. In my case there does not appear to be such a correlation:
Also interesting, the amount of deep sleep seems somewhat unrelated to the amount of total sleep — ~4 hours of deep sleep regardless of whether I'm sleeping 6, 7 or 8 hours:
To put it another way, % Deep Sleep declines somewhat as my # of hours of Total Sleep increases:
Next step is to correlate my sleep to my performance in StarCraft and Chess. :)
Also, I'm now highly motivated to do a better job of recording my sleep data accurately. Some of the really short sleep durations are not accurate, and are due to me forgetting to hit the button on the Jawbone UP before going to sleep, or to me forgetting to keep it charged.