I've seen a lot of tests measuring execution speed of programming languages, but I've never found tests measuring development speed.I've heard development speed is increased when working with dynamic languages, but is there any proof of that ? I'm not trying to say dynamic languages aren't efficient, but I'd kind of like to see the results of a scientific study, if such a thing exists.Even better would be informations on maintenance facility. Are some languages easier to debug than others ?EDIT : I'm mostly interested in the differences between two languages that are close in syntax. For example, I guess programming in C will usually be slower than programming in Java; but is programming in Java faster than programming in C# ? 
A measure of development speed
programming languages;comparison
Absolutely the programming language makes a difference. However, I think that difference is far more about how familiar the programmer is with each language than any particular aspect of the language, especially given your constraint of languages with similar syntax.