By David Biderman, in the Wall Street Journal of June 28, 2010.

And now for some breaking news: A lot of players fake injuries during soccer matches!

OK, maybe that’s not so newsy – flops have been a way of life in sports for many years.  But after a handful of seemingly overblown falls toward the end of Saturday’s U.S. loss to Ghana, we decided to try to make some sense of them.

The most common indicator that a fall is a flop is that the player gets hit, pauses briefly and then reacts.  This is called a “temporal continuity” error, according to Paul Morris, a psychology lecturer at England’s University of Portsmouth – he says it occurs in about 29% of fake injuries.

Meanwhile players perform the “archer’s bow” pose in 28% of flops, which is when they bend backwards and throw their arms in the air when they are hit in order to gain a referee’s attention.

Dr. Morris worked with two groups of raters to watch about 400 tackles. They classified which ones included injury exaggeration and, among those, what type of exaggeration was employed (his previous injury research was published earlier this year in the Journal of Nonverbal Behavior).

One prominent example of likely flopping Saturday came late in extra time when Ghana’s Samuel Inkoom fell to the ground after kicking a ball – despite not being touched by another player. He began to get up but opted to lay on the ground and delay the game for 92 seconds – a tactic that helped preserve Ghana’s lead.

Mr.Inkoom was carried off on a stretcher – although the moment he reached the sideline, he climbed off under his own power.

According to Dr. Morris, this was a “ballistic continuity” issue – a fake-injury variation that occurs in 25% of all flops.

Here are the four most common giveaways for exaggerated injuries in soccer games.

How to spot it:

“Temporal Contiguity” – Too much time between contact and reaction. (29%)

“Archer’s Bow” – Player bends backward and raises arm to get Ref’s attention. (28%)

“Ballistic Continuity” – Too much reaction for limited amount of contact. (25%)

“Contact Consistency” – Player gets hit in one area but says another area is hurt. (15%)

(Source: University of Portsmouth)