"This is quite a quantitative study which gives credence to the claims of advocates of dynamic languages" You have to be careful with that. In a dynamic langu

"This is quite a quantitative study which gives credence to the claims of advocates of dynamic languages" You have to be careful with that. In a dynamic language your test system is your compiler. It is essentially a domain specific compiler. With a statically typed language, half your tests are already written, and you just have to activate them with a type signature. For my money the trade off is down to whether forcing structures into a type system and getting the 'free advanced tests' is more advantageous than constructing a domain specific test harness 'compiler' and getting the flexibility of duck typing. And you only learn that when you run up against the limits of the type system and have to start complicating structures to work around it. In terms of a rough metric I'd suggest you have to include the test code in both cases to get a fair comparison.