Is Game 1 a must-win game?

Joe Sheehan of Baseball Prospectus blogged today about the relative importance of Game 1 toward winning a World Series. He writes:

Winning the first game of a World Series is a strong indicator of future success. The last five World Series have been won by the Game One victor, and all-time, the winner of the first game is 63-40 in the Series.

But is it more important to win Game 2 than Game 1? Let's take a look at the World Series since 1980:

1980: Game 1 winner-Phillies; Game 2 winner-Phillies; World Series winner-Phillies
1981: Game 1 winner-Yankees; Game 2 winner-Yankees; World Series winner-Dodgers
1982: Game 1 winner-Brewers; Game 2 winner-Cardinals; World Series winner-Cardinals
1983: Game 1 winner-Phillies; Game 2 winner-Orioles; World Series winner-Orioles
1984: Game 1 winner-Tigers; Game 2 winner-Padres; World Series winner-Tigers
1985: Game 1 winner-Cardinals; Game 2 winner-Cardinals; World Series winner-Royals
1986: Game 1 winner-Red Sox; Game 2 winner-Red Sox; World Series winner-Mets
1987: Game 1 winner-Twins; Game 2 winner-Twins; World Series winner-Twins
1988: Game 1 winner-Dodgers; Game 2 winner-Dodgers; World Series winner-Dodgers
1989: Game 1 winner-A's; Game 2 winner-A's; World Series winner-A's
1990: Game 1 winner-Reds; Game 2 winner-Reds; World Series winner-Reds
1991: Game 1 winner-Twins; Game 2 winner-Twins; World Series winner-Twins
1992: Game 1 winner-Braves; Game 2 winner-Blue Jays; World Series winner-Blue Jays
1993: Game 1 winner-Blue Jays; Game 2 winner-Phillies; World Series winner-Blue Jays
1995: Game 1 winner-Braves; Game 2 winner-Braves; World Series winner-Braves
1996: Game 1 winner-Braves; Game 2 winner-Braves; World Series winner-Yankees
1997: Game 1 winner-Marlins; Game 2 winner-Indians; World Series winner-Marlins
1998: Game 1 winner-Yankees; Game 2 winner-Yankees; World Series winner-Yankees
1999: Game 1 winner-Yankees; Game 2 winner-Yankees; World Series winner-Yankees
2000: Game 1 winner-Yankees; Game 2 winner-Yankees; World Series winner-Yankees
2001: Game 1 winner-DBacks; Game 2 winner-DBacks; World Series winner-DBacks
2002: Game 1 winner-Giants; Game 2 winner-Angels; World Series winner-Angels
2003: Game 1 winner-Marlins; Game 2 winner-Yankees; World Series winner-Marlins
2004: Game 1 winner-Red Sox; Game 2 winner-Red Sox; World Series winner-Red Sox
2005: Game 1 winner-White Sox; Game 2 winner-White Sox; World Series winner-White Sox
2006: Game 1 winner-Cardinals; Game 2 winner-Tigers; World Series winner-Cardinals
2007: Game 1 winner-Red Sox; Game 2 winner-Red Sox; World Series winner-Red Sox

OK, we have a lot of data here. Here are the World Series records of each winner:

Winner of Game 1: 19 wins, 8 losses
Winner of Game 2: 18 wins, 9 losses

That tells me that it's just about as important to win Game 2 as it is to win Game 1.

Let's delve a little deeper.

How often does the team that loses Game 1 but wins Game 2 win the Series?

Not very often. Those teams have a record of 3 wins, 6 losses (the winners being the '82 Cardinals, '83 Orioles, and '02 Angels)

How often does the team that wins Game 1 but loses Game 2 go on to win the Series?

About even. Those teams have a record of 5 wins, 4 losses (the winners being the '84 Tigers, '93 Blue Jays, '97 Marlins, '03 Marlins, and '06 Cardinals).

I could go on, analyzing home field advantage, quality of starting pitchers, and so on. But unfortunately, all we're going to discover is that, in a seven-game series, EVERY game is important. It's better to win than to lose.

Sorry the conclusion isn't more enlightening than that.