How do we define a valuable player? That very question will be asked over and over again early next week when the American League and National League MVPs are announced by the Baseball Writers’ Association of America. On a slightly smaller stage, each team will be asking themselves the same question as they look to improve their rosters during the off season.

Will Player A at Position X be an improvement over Player B at Position X, considering that Player B can be moved to Position Y? Or, in less formulaic terms, how does a player’s production compare to the rest of the players who field his position?

This question is an especially important one when considering the Miami Marlins’ pursuit of Jose Reyes. The addition of the former Mets’ shortstop would most likely cause Hanley Ramirez, the Marlins’ current shortstop to move over to third base, a shift with which the young superstar would not be entirely thrilled to commit himself.

I’m the shortstop. I’ve always been a shortstop.

While it’s hard to argue with that brand of reasoning, there’s little question as to whether or not Reyes is better at fielding than Ramirez. Last year in New York, Reyes put up the poorest defensive numbers, always somewhat suspect, of his career. However this low equals a typical season from Ramirez.

While the lack of softness to Ramirez’s hands may be the subject of some ridicule, the biggest difference between the two fielders according to annual crowd sourcing is their arm strength. Ramirez is judged by the fans to have a worse arm than Yuniesky Betancourt.

It’s somewhat speculative, based around the breakdown of his UZR rating, but I wonder if his lack of arm strength causes him to rush balls in play for which a superior shortstop could afford to wait. His barely below average work on double plays over the course of his career suggest to me that his hands and feet aren’t horribly positioned when he doesn’t have to throw all the way to first base.

If this is true, placing him at third base could potentially be a horrible idea.

For the sake of argument, let’s assume that what I’m suggesting is true, and a lot of Ramriez’s defensive inability is rooted in his poor arm. His new position would not only result in a decreased value in positional adjustment for moving from shortstop to third base, it’s likely to also result in little change to what his defensive metrics tell us. At the very least, this means a half win above replacement drop off. His WAR could fall off even more drastically if we anticipate additional struggles for Ramirez as gets used to his new position.

It seems to me that the best course of action, if the Marlins do indeed acquire the services of Jose Reyes, is to shift Ramriez the other way toward second base. His lack of arm strength wouldn’t have the same negative impact as it would manning the hot corner, and his close to average fielding of double plays suggests that second base wouldn’t be as big of a chore to master. While the positional decrease in value would be the same as a move to third, an anticipated defensive metric improvement would leave Ramirez contributing a similar level of wins above replacement to what we’d expect from him playing shortstop.

Such a move wouldn’t be unique. While it’s not shocking that most teams field the better defensive player at second base, the average second baseman is actually better offensively than the average third baseman.

Unfortunately for the Marlins, prior to the end of this season, the team inexplicably locked up Omar Infante, agreeing to pay him $8 million for the next two years. His defense at second base this past season makes his total wins above replacement in 2011 look better than it is, but over the course of his career he’s been only slightly above average at second.

His career numbers at third base are actually a little bit better, but more recently those metrics point to his having a horrible season in 2010 with 139 innings at third. Prior to that, he was judged to be consistently above average defensively at third.

All of this is to say that, while it seems unlikely that the Marlins would be willing to shift Infante to third base and put Ramirez on second base (there’s even been more talk of him in center field than second), given where the Marlins’ current shortstop’s defensive shortcoming lay combined with Infante’s history at the hot corner and the six year $90 million contract that the Marlins reportedly offered Reyes, it would be a mistake not to at least test drive Hanley Ramirez at second.