Early Risers Crash Faster Than People Who Stay Up Late
scientificamerican.com
scientificamerican.com
I know that when we run A/B tests on our website, and calculate confidence intervals, we often need thousands of conversions before we see results that we are convinced are statistically significant.
All groups are different. Let me repeat. All groups have different means. The magnitude of the difference (difference between means) is called the effect size. If the effect is large you need a trivial amounts of data. If the effect is small you need lots.
The only thing p is telling you is whether you can reliably tell the datasets apart. It's NOT telling you how far the datasets are apart, which is what you really want to know - does this change cause a large difference.
15 years ago a circadian rhythms expert told me that early risers are people whose natural rhythm is shorter than a day. Night owls are people whose natural rhythm is longer than a day. Since the average human cycle is 25 hours, more people tend to be night owls than early birds.
This sounds like extra detail on that.
How many night owls would not be night owls if they didn't have electric lights?
The one befit of this insomnia is that I kind of learned where my triggers are sufficiently well to induce sleep if I absolutely must be up early for some reason. But frankly, it's easier for me to pull an all-nighter, especially if I'm going to be on a plane or something where I can reasonably go to sleep as soon as I'm strapped in.
My solution is to drape an old shirt over my eyes. Works great. There are also miniature pillows that are sold for the same purpose, but they are not as comfortable as the shirt for me.
Note: This is not the only similarity between myself and the man of steel.
However...if I go to the climbing gym at, say, 6:30PM or 7PM, and stay for 90 minutes, I can make it a little further into the night without being tired.
In other words, if someone who is naturally a night owl becomes an early-riser by force of practice, will they retain this "second wind" in the evenings?
With my 2am-9:30am sleep cycle, I could stay alert until pretty much any time I liked (very useful for writing a PhD, etc). Now that I am forced to wake up at 7:30am, I find myself crashing at 10pm.
I think late risers listen to their body and get more sleep. This leads them to be more alert, because they're not running a deficit. They might need 1/2 hour more sleep, and get it (when needed).
As a night person, I find it harder to explain why I feel more productive after the sun has gone down. There is some support now for the idea that this can be an actual medical condition in some cases (http://en.wikipedia.org/wiki/Delayed_sleep_phase_syndrome) affecting <1% of the population, though about ~15% of people are thought to be night owls with a general preference for the evening hours but not inability to sleep earlier if they choose.
Though it's not something I, um, lose sleep over, I do think that society inadvertently discriminates against people with an evening orientation.
I find it horrific that many American schoolchildren are expected to begin lessons at 8am - unless I am working really long days where I'm worn out physically as well as mentally (so I sleep early), I generally can't function at all before 10am. In Ireland school starts at 9am and my childhood memories are dominated by difficult wakening, rushed breakfasts and persistent lateness. I have major reservations about how I'm going to handle this when we have kids, which will be soon.
http://www.atavist.net/evan/images/MensJournal/MJ_Provigil_R...
As for the point of the article, sleeping the 4 AM to noon shift seems to be stable for me because I never seem to "crash" on that schedule as I sometimes do on others. I can stay up much longer than 4 AM, even completely miss a sleep period, and still be back to 4 AM to noon the next day; I cannot do that with other sleep schedules.
http://en.wikipedia.org/wiki/Statistical_power
Please educate yourself, and return if and when you have something useful to say.
They sampled 31 people. Would you accept a 31 person study over a two week period for a new pill in which "most" of the people given the pill (16 out of the 31) were now immune to any form of cancer? Or would you require more people in the study and/or longer, more rigorous testing before you took the pill yourself or gave the pill to your family?
Get over yourselves. 31 effing people.
Complaining about a small sample size screams of ignorance; there's nothing wrong with shameless extroversion, thespianism, or small sample sizes. If you want to point it out and be meaningful, comment on the sample size in relation to the effect size in a way that includes statistical power. Say something. Don't just echo things you've heard other people say.