http://www.nandahome.com/

Clearly what we need is an improbabilistic alarm clock. What would Douglas Adams do?

I’ll note my preference at the outset: I have two radio-controlled clocks, a clock radio and a watch; my computer contacts the NIST timeserver daily; the landline phones get the time via caller ID; the cable tuner’s time is set remotely. (The thermostats, ovens, coffee maker and sundry other timepieces are manually adjusted and undependable, and yes, changing to and from daylight savings time is a major festival in my household.)

In my experience, people who try to compensate for running late by fooling themselves continue to run late, probably because it’s hard to forget that you’re lying to yourself.

For a commuter, an alarm connected to the net and tracking traffic delays could conceivably be useful, but the option of an additional aleatory uncertainty would not.

Why do you need the trick in the first place? Because when your clock shows exact time you are often late.

Why are you often late when your clock shows exact time? Because you’re irrational.

In what way are you irrational? You are irrational in the sense of being too optimistic; IOW: when you calculate the odds, you make systematic mistake assuming they are too favorable.

I’m saying that this probabilistic clock just gives you an additional opportunity to miscalculate the odds, and, obviously, with the same bias we already know you have (too optimistic), and so you’re probably going to be late more often than usual.

No, your clock is not +- 10 minutes, it’s always ahead, it’s ahead by between 5 and 15 minutes and you know it.

I don’t think that matters. Let’s say the meeting is at time m and whatever time you try to arrive at (a) you will end up arriving at a+r, where r is in the range negative 5 to 5 (because your estimate of the time may be out by plus or minus 5 minutes). You will not (rationally) set a to m, because the penalty for being late is larger than the penalty for being early. Depending on the relative size of these penalties you will set a to some number less than m, possibly to m minus 5.

I don’t think that matters. Let’s say the meeting is at time m and whatever time you try to arrive at (a) you will end up arriving at a+r, where r is in the range 5 to 5 (because your estimate of the time may be out by +/- 5 minutes). You will not (rationally) set a to m, because the penalty for being late is larger than the penalty for being early. Depending on the relative size of these penalties you will set a to some number less than m, possibly to m5.