Imagine a boss who constantly belittles his employees' contribution, wildly undervalues their efforts, and always offers nasty, personal formulations for his unfair feedback.

Now, try to imagine an even worse boss.

Stumped? Perhaps science can help.

New research out of Michigan State University that was recently published in the Academy of Management Journal used both lab experiments and field surveys to discover who has it worse, teams led by straight-up jerks or those helmed by unpredictable loose cannons. This might come as cold comfort to those with constantly nasty supervisors, but apparently people employed by erratic leaders actually have it worse.

Always evil beats sometimes nice?

To come to this conclusion, the research team separated subjects into two groups and asked them to play a stock-pricing game. One group played the supervisor and the other the employee while the researchers monitored them for an elevated heart rate, a sure sign of stress.

If the study subject playing the supervisor provided fair feedback, unsurprisingly, all was well. But when the boss became unfair things got interesting. It turns out that having a boss who is consistently unreasonable and nasty raises stress levels less than having one that swings between behaving like a decent human being and being a complete monster.

"Our findings essentially show that employees are better off if their boss is a consistent jerk rather than being a loose cannon who's fair at times and unfair at other times," commented lead author Fadel Matta. "Inconsistent treatment is much more stressful than being treated poorly all the time."

It's a finding that's slightly counterintuitive at first, but one that begins to make sense once you think about -- at least if your boss is always obnoxious you know what to expect. This conclusion was born out by a survey of real-life workers conducted by the team as well. Employees with moody, changeable bosses reported more stress, job dissatisfaction, and emotional exhaustion than those who were simply treated poorly all the time.

Boring is great!

These results might surprise some, but they'd probably come as no shock to Google HR bosses. When the search giant went looking for the key attributes of great leaders, it didn't come up with anything grand like strategic boldness or stirring motivational powers. Instead, the company's hard look at the data revealed something kind of snooze-worthy - great bosses are incredibly boring.

For Google, the benefit of boredom is freedom. If you know what your boss is going to do, you can spend less time and energy playing politics and more executing great ideas. "If a leader is consistent, people on their teams experience tremendous freedom," VP of people operations at Google Laszlo Bock has been quoted as saying.

This new research backs up Google's claim that a good boss is a boring boss but for more mundane reasons -- worrying about what your boss is going to do isn't just a distracting waste of time, it's also super stressful.

The takeaway for supervisors couldn't be simpler (though perhaps it's more difficult to put into action then it initially sounds): aspire to be totally predictable and utterly boring. Your team would thank you... if they bothered to think about you. But hopefully you'll be too boring and they'll be too busy working.