If work gives you the blues, you might want to ask for a raise on the basis that you're probably more productive than happy coworkers. At least that's what Robert Sinclair and Carrie Lavis of the University of Alberta have recently concluded from four different studies. Their findings will be presented at a meeting of the Canadian Psychological Association this June.

The researchers tried to measure the effect of moods on productivity by testing happy and sad people as they assembled circuit boards. It turned out that sad people were far better builders. The scientists suggest that perhaps sad people concentrate harder on their work because it takes their minds off of whatever makes them sad. In contrast, the happy people don't want to be distracted from bliss.

So does that mean employers should make their workforce miserable to boost efficiency? Not quite. The key message of the study, Sinclair says, is that organizations should realize that employees' emotions influence their performance (no great surprise there). He also suggests that employers should create situations in which employees feel that doing their jobs will make them feel good. Stock options anyone?