Convergent or divergent?
Well, since yankees > Redsox (though not this year) I'd say convergent.
The Yankees haven't been better than the Red Sox since 2004.
Divergent. Both teams are in the American League so they can't both be in the World Series. Either Yankees or Red Sox has to equal 0 for any given year.
It does raise an interesting thought though as time advances unbounded in terms of the number of World Series played.
What will World Series #1,000 or #10,000 be like? Will they always be played? Or will interest in baseball eventually evaporate? It wasn't that long ago that people amused themselves by watching gladiators and/or animals fight to the death. Now it's not that easy to find a good bull fight. (Though I suppose Michael Vick knows where to find dog fight still.)
Just imagine the interminable replays of the eons of Top 10 plays to plow through and the arguments about whether the 3349 Phillies were better than the 2457 Caracas Flamingos.
Baseball history is not as lopsided as people assume. Out of the 105 AL pennant winners so far, 51 of them have either been occupied by Boston or New York. That's 48.6% of the total AL pennant winners. That's still a good amount for two teams combined, but not even close to substantiating the "they're in the World Series every year" exaggeration.
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