It’s astounding how many people use the median of anything to figure out a budget. How much money to have in their bank account, how much time to dedicate to a project, when they should leave the home to be at work.

Google maps uses the median of a distribution to estimate how long it takes to get somewhere. If you too, use that median, you’ll be late 50% of the time. You’ll overdraft your bank account in 50% of your paychecks. You’ll miss your deadline 50% of the time. And we ask ourselves, why, why does this keep happening? People are cripplingly stupid creatures.

I’d prefer to treat my endeavors like a science experiment, give me the 95the percentile of the distribution. I can tolerate being late 5% of the time, dipping into my savings 5% of the time, finishing my work with a similar confidence. To do this I’ll generally double the median, annoying as it sounds. Does google maps say I need 30 minutes? I suppose I’ll give myself an hour. Do I usually spend $5,000 in a month? May as well keep $10,000 in my bank account.