Contribution can be translated either as () and ().
* : beneficial contribution from people (by money, labor, source code, etc)
* : contribution of various inanimate factors (e.g., price, demand, temperature, ...). (can be positive or negative)
* : value, degree
If you are asking how much the "practical experience" has affected something, is probably the best choice.
I don't know the context, but "practical experience" can be translated differently. Please make sure is the right translation in the context in question.