The midseason transfer window is about to open for MLS but trades are fair game.  Today the New York Red Bulls swapped attacking midfielder Dwayne DeRosario (acquired in another trade earlier this season) for DC United’s holding midfielder Dax McCarty.  This is an interesting trade on many levels (salary cap hits, contract length, etc) but what struck me most was that NY was bringing in defensive reinforcements after a spell of poor defensive performances.

Looking at the moving average of NY’s goals against and DC’s goals for, you can see a trend of a stalling offense and a leaking defense.  Are these legitimate problems or just slumps?  For NY, they’ve certainly been suffering from the absence of Tim Ream and Rafa Marquez, but the problems started long before they had to report to their national teams for the Gold Cup. Regardless, there are two interesting factors in decision making that might be coming in to play here.  The first is recency bias — the attribution of more weight to more recent data/information than older info.  Basically, you remember the recent stuff better so you consider it more important and the opposite is true for older stuff.  The fact that NY kept clean sheets in 5 of their first 7 matches is long forgotten, replaced by images of Greg Sutton gifting the ball to Roger Levesque for an embarrassingly easy goal.  The other issue that might be coming in to play here is prospect theory.  Depending on the team’s frame of reference, swapping players, and the expected gains can look attractive or unattractive.  Making the trade early in the season might not have been attractive to NY, but now that they are feeling vulnerable defensively, it looks a lot more attractive.  People are also less risk adverse if they are feeling poor and view the risk as having a large upside and relatively low downside since there isn’t much to lose.  This is the sort of situation NY finds itself in now.  Certainly there are other factors that came into the trade decision, but I think it’s important to understand how data could have played a part and some of the caveats that come with it.  The data points to NY having defensive problems.  Understanding how the mind makes decisions and some of the biases and pitfalls that go along with that can help lead you to making the best decision based on that data.