"Research done by the Free University of Bozen-Bolzanohas in Italy concluded that happy software developers are better at solving analytical problems. 'Even simple and short activities', the researchers note, 'may impact the affective states of software developers.'
Many large software companies have been providing various perks to developers, hoping that they will become more productive. Based on a study of 42 students from the Faculty of Computer Science, this research seems to validate that practice. Its findings suggest that 'the happiest software developers are more productive in analytical problem solving performance.' This is in contradiction to previous studies, most of which concluding that negative affective states foster analytic problem-solving performance.
I'm tempted to say that this might be the same for any kind of work really. A happy worker is a productive worker.
I would argue that it has a bigger effect on software developers' productivity that it would in non-creative jobs, like movie projectionist. Whether the person projecting a movie is happy or sad is largely ineffectual on their work. When a software developer is demoralized, you can get some truly awful code.
I would argue that it has a bigger effect on software developers' productivity that it would in non-creative jobs
This is essentially the crux of the study. The participants who were happier did better at the analytical tasks - a skill that is very important for programming.