I can't read the paper you link but in the abstract-ish thing you've given here, $20 is a mean. The MIT paper says $3.37 is a median. Both could simultaneously be true!
I agree that the mean and median could in principal be this far apart, but it would require a lot of skew in the data (small number of very high value trips -- seems possible).
I agree that the mean and median could in principal be this far apart, but it would require a lot of skew in the data (small number of very high value trips -- seems possible).