It might be time to upgrade your company from the bottom up and purge the company of employees with poor attitudes. If that sounds harsh, it's not. Behavioral research suggests that groups don’t lift the performance of employees with bad attitudes. Rather, the bad attitudes drag down the group.

The theory has always been that groups lift the performance of poor performers. However, Dr. William Felps of the Rotterdam School of Management discovered that's not the case.

Felps' specialty is researching the negative effects of bad apple teammates, the contagion of quitting (i.e. turnover), the nature and performance implications of stakeholder cultures, the effects of defining oneself as a moral person, and most recently, he's been studying whether generalists can ever outperform specialists.

In this case, Felps led a team of researchers who assembled college students into groups of four. The groups were assigned tasks, given 45 minutes to complete the task, and incentivized with a $100 per student award offered to the group that did the best. Perennially poor, obviously the college students were motivated.

To study the effect of negative behavior, an actor was inserted into some groups. The actor purposefully behaved as a jerk to others in the group, a slacker, or a depressive pessimist. Felps' team videotaped the groups to provide an observational record to supplement to results of the assigned tasks.

In the role of a jerk, the actor would belittle other group members. He would question their knowledge. The jerk was quick to tell others why their ideas wouldn't work.

As a slacker, he would show disinterest. He would tune out of the group activity and effort by texting to friends. He showed that he was simply biding his time until he could leave.

As a depressive pessimist, the actor complained about the work. He expressed negative views about the group's ability to succeed.

Do these "bad apples," as Felps called them, sound familiar? Are they present in your company? If so, they could be dragging everyone down. In Felps' research over dozens of groups, the groups with the actor performed 30% to 40% worse that the groups without the actor. That's huge!

Moreover, Felps observed that groups began to mimic the behavior of the actor. When the actor was a jerk, the group began to act similarly. When the group would start with everyone sitting up straight and being attentive, the actor might rest his head on his desk. By the end of the session, everyone in the group was resting their heads on their desks.

Felps did note that one group broke the mold. In this group an exceptional leader emerged who took charge, drew everyone out, and smoothed over conflict.

Even so, Felps found that the best predictor of team performance wasn't how well the best team member performed, or even how well the average member performs, but how well the worst performs. Maybe your great leadership can overcome bad attitudes, but why risk it?

Anyone who has ever run a company or led a group can attest to the impact of a negative personality on everyone else. By the end of the day, even the sunniest individual is affected. Negative individuals are like black holes filled with negative energy sucking the life out of your organization and everyone in it. More than the economy, the negative energy generated by these people hold your business back.

Give the jerks, slackers, and pessimists in your business the chance to change. You owe them that. You hired them. However, if they can't or won't change, change them. While this sounds harsh, there are simply too many top-shelf people in the job market today. Why tolerate anyone who drags your company down?

Instead, build your company with individuals holding can-do attitudes, from the bottom up. Associate with other business owners holding similar outlooks. Support vendors who are upbeat about your company's prospects and who are focused on your success. Get involved with a local service club filled with positive people. Join a networking group.

In 2011, purge your company of negative energy and see how good this year can get!

Matt Michel is CEO of the Service Roundtable. For more information call toll free 877/262-3341, visit ServiceRoundtable.com, email at matt.michel@serviceroundtable.com or connect through Facebook, LinkedIn, or Twitter.