A new job site called CareerCast.com recently ranked the top 200 professions in the United States. Interestingly, mathematician took first prize, and biologist came fourth. In fact, several science-related professions scored quite well. Statistician was third, physicist thirteenth, meteorologist ranked fifteenth and astronomer twentieth. But the list did not consider job satisfaction or experience needed, which might unfairly skew its results.

The site used five core criteria to draw up its list: environment, income, outlook, physical demands and stress. Yet none of these looked at what it takes to become a 'biologist' — the many years of hard work, schooling, stress and intense competition. If the entire career path were taken into account, some jobs could lose their lustre.

Perhaps more significant was a bias towards desk jobs. Consider some of the worst-ranked professions. At number 200 was lumberjack, seaman ranked 197 and ambulance workers (emergency medical technicians) 196. The rankings tend to classify these jobs as unsafe or arduous; but arduous can be a good thing.

Under environment, for example, one of the criteria scored was 'physical components'. And the stress criteria included 'hazards encountered', 'initiative required' and 'stamina required'. The more points a job received, the worse its rank. This could be misleading. Emergency medical technicians might find their job tremendously rewarding, despite the stress. The same goes for less highly ranked field scientists who might have more taxing daily duties. The pages of Naturejobs include many examples of research and postdoc positions that push scientists' physical as well as mental capacities (see, for example, Nature 446, 226–228; 2007).

Rankings such as these are intriguing, but not bias-free. Ideally, they should relate their results to a survey on job satisfaction. After all, the best jobs are the most satisfying, not necessarily those with the lowest stress. Mathematicians may be expected to have good jobs, but are they happy? Lumberjacks are paid little and encounter danger on a daily basis. But, as they dodge falling trees amid the dense aroma of cedar, are they really that miserable?