For fans of FareCast, there is a cool new site called DelayCast that’s just gone into beta.
Type in the airport codes for your departure and arrival cities and the date and site come back with predictions about the probability of cancellation and delay for different airlines serving the route. For example, here are the results for a trip from Chicago (ord) to Hartford (bdl):
And in true Super Crunching fashion, DelayCast not only predicts but gives the 90 percent confidence interval for the prediction. The site’s F.A.Q. explains why their predictions are better than the government’s on-time statistics.
Now what I’d like to see is a DelayCast for other parts of my life.
In particular, I’d like to have a statistical algorithm for accurately “translating” the delay predictions of pilots. My strong sense is that when a pilot comes on the intercom and tells you that the plane will be taking off in 10 minutes, the passengers should expect the plane to leave in 15 or 20 minutes. (The true distribution is skewed right and a good Bayesian would also increase the probability that the flight would be canceled).
Instead of trying to get pilots to speak more honestly about delays, I think we’re more likely to be able to produce a translation program:
When pilot says X, passengers should hear Y.
You can help create such a program. For the next week if you’re traveling by air, please pay attention to all the predicted delays and compare them to the actual delays — and post your numbers as a comment to this post. (I’m a bit scared that people will disproportionately report when they are frustrated by an unexpectedly long delay — so the data is likely to be unrepresentative.)
But if we get enough data, I’ll crunch some numbers. The exercise underscores the needless (or maybe I should say self-interested) bias in many human delay predictions.
When a home contractor says your kitchen renovation will be done in two weeks, you’d be foolish to start sending dinner invitations. But it would be nice to know whether two weeks means three weeks or two months.
and 
. You can also watch it on 
Are you implying that pilots give inaccurate predictions about expected take-off and landing times? That’s unheard of!
I flew today on JetBlue from Boston to DC. We were on time, and in fact 20 minutes early!
I’m not sure how useful confidence intervals are on probabilities. I’m pretty sure expected utility theory tells me I only need to look at the mean…
Today on a flight from Chicago to JFK on Jet Blue we were informed that we would have a 5 to 15 minute delay. Well, after 5 minutes, it was announced that we would be delayed 3 hours. We ended up leaving and arriving 2 hours late.
And the tvs didn’t work.
Today on Southwest from San Diego to Austin.
Original Departure scheduled time: 3:30pm
Delay announced ~ noon: 4:10pm
Further delay announced ~ 3:00 : 4:30pm
Further delay announced ~ 3:30: 4:35pm
Actually pulled out from the gate at 4:45pm.
Departure delay isn’t all that interesting. What I want to know is if we’re going to arrive on time. I believe that they have some room for departure delay, when they first tell you they arrival time. Most of my flights that depart 15 minutes late, still arrive on time.
My 7:05p flight from Boston to Chicago last Sunday was reported to be delayed until 9:45p. It was then announced 10:45. Then 11:30. The plane took off at midnight.
there’s also a law of bus delays- when a bus is late, and there are too many people to board, the driver will always say “there’s another one coming right behind me”- I used to think this was evil, but realized it’s a survival technique- not wise to not indulge an angry mob