There is always much debate in professional sports about which players are overpaid or underpaid, which ones are the most efficient on the floor, and which ones are simply the most productive. But what about a marriage of all of those? Which NBA players are the most cost-efficient?

This is the second piece in a series looking at the starters at all five positions (check out the PGs), one at a time, in an attempt to determine which players are the most cost-efficient players, taking into account their production and salary. The assumption is there should be a general correlation between a player’s production – and for this purpose we will use John Hollinger’s Player Efficiency Rating – and his salary.

Will that hold true? Take a look at the list of starting shooting guards below, with their 2010-11 salary and PER, plus a final column dividing their salary by PER to give a simple dollar amount of how much each point of PER cost their team.

Just as with the piece earlier this week on point guards, the most cost-efficient shooting guards in the league are players still on their rookie contracts. Chicago’s Keith Bogans, on a veteran’s minimum contract, stands out, but so does Memphis’ Tony Allen. In fact, Allen is the only player in the top 12 not on a rookie contract and making more than minimum – his sparkling 18.4 PER is icing on the cake (note that 15.0 is considered average).

What jumps out most to me is the total at the bottom. The AVERAGE PER of this group is 14.1. So, if I read that right, the average starting shooting guard in the NBA is, according to efficiency statistics, lower than average? That’s sad. Compare that to the average PER of the starting point guards – 16.8. Even with the drastic difference in average PER, the players on this list earned an average of $200,000 more.

At the bottom of the list we find Vince Carter, which probably isn’t a surprise. With a just below average PER and the second-highest salary it was inevitable. He barely beat out Kobe Bryant, but Kobe’s 23.9 PER is second on the list only to Miami’s Dwyane Wade (25.7), and no one in their right mind would suggest Bryant isn’t worth the money.

Taking into account production and salary, the most cost-efficient starting shooting guard in the NBA is probably either Wade or Houston’s Kevin Martin, just edging out San Antonio’s Manu Ginobil by virtue of age. Wade brings a better defensive game than Martin, something not reflect in PER, plus has a more varied offensive arsenal, which makes up for the difference in their cost-efficiency.

Here’s a fun exercise for this list. By definition the average PER is 15.0 and in 2010-11 the average NBA salary was $4.63 million (the average of 435 full season contracts). Take another look at the list with those numbers in mind. How many players failed to reach an average PER but made more than the average salary? Three: Carter, Charlotte’s Stephen Jackson (now with Milwaukee), and Milwaukee’s John Salmons (now with Sacramento). Considering Carter is expected to be waived due to his contract not being fully guaranteed if the lockout ends in time to save the 2011-12 season and the other two were traded at the 2011 NBA Draft, it’s safe to say none of their teams were pleased with their starting shooting guards.

All in all, most teams shouldn’t be thrilled with their starters at the two at all for the 2010-11 season.

What do you take from this? Leave your thoughts in the comments below! Follow Jason Fleming on Twitter.