I know it's unfair to generalize, but seriously if we'd had to put numbers on it and perform statistics on it (something most psychology degrees are pretty capable of even though the way they do it might raise questions) I'm rather sure the outcome would be close to: sorry, but 90% cannot write good code. Why I think this? Because I've seen and fixed code written in multiple laguages by psychology degrees (about 20 in total, from more than one institution) for the last ten years. And there are just no words for how awful it was. Hell, I've seen matlab scripts in which I would use the same dataset for both dataset arguments and still the result was there was a statistically relevant (p < 0.01) difference between the two.