Janus, I understand that my position is somewhat contradictory to people who love static types, and it always generates some lively debate. I did, after all, come to it after years of working with Miranda and even today I work a LOT with Scala. So I am very familiar with the latest and greatest in static typing, but at the end of the day, comparing Scheme vs Miranda, and Racket vs. Scala I cannot help but conclude that the static typing is doing nothing for me or for the engineering projects we take on. If anything, development in Scala is a lot slower without buying any quality guarantees.

While I only speak from personal experience others have tried to take a more scientific approach to it. I ran into this talk where the speaker actually spent some time measuring the effects of static vs. dynamic types. The talk is long (nearly an hour), but he speaks well and brings out some interesting points. Nothing conclusive, of course, but it will make you think. https://vimeo.com/74354480