How often does neither starting pitcher get a decision?
Posted by Andy on April 1, 2011
Here on Opening Day we've already had a few games where neither starting pitcher got a decision in the game. I know that's not all that rare, but I got curious to see just how often it happens.
I did a Pitching Game Finder and sorted by most players meeting the criteria, and simply clicked the bubbles for starter and no decision.
For 2010, there were 570 games in which both starters got a no-decision. There were 231 games in which 1 starter got a no-decision and the other starter got a decision. Since there were 2430 total games, that means there were 1629 games in which both starters got the decision.
On a percentage basis, that's 23.5% of games with a double no-decision, 67.0% of games with a double decision, and 9.5% with one of each.
Just out of curiosity, I checked the numbers for Opening Day games. To get a little more data, I went back to 2006 for 5 seasons'-worth of data. There have been 23 Opening Day games in which both starters got no-decisions. There have been 7 games in which one starter got a no-decision. There have been 45 games in which both starters got a decision.
That's 75 total games (which makes sense since there are 30 teams, meaning 15 Opening Day games per year, times 5 years.) It breaks down to 30.6% of games with double no-decision, 60% of games with a double decision, and 9.3% games with one of each.
April 1st, 2011 at 10:59 am
Interesting. Anyone know what the historical pattern if for no-decisions?
April 1st, 2011 at 11:00 am
and??
9.1% of games with one of each?
April 1st, 2011 at 11:03 am
Laugh, thanks Jeff, I fixed that.
I was talking to my wife last night just as a finished the post and must have forgotten to actually type that in.
April 1st, 2011 at 12:21 pm
Seems to make sense that the percentage of double no-decisions would decrease in years with a higher number of complete games. The longer a starter goes, the more likely he'll end up with a decision.
April 1st, 2011 at 12:34 pm
And extra inning games are likely to be double-NDs, especially now.
April 1st, 2011 at 3:49 pm
I would guess Opening Day has a higher % of double no-decisions (30% for Opening Day vs 23% overall) for a couple reasons (purely speculative).
1) because I would also guess starting pitchers are going to pitch less innings during their first few starts than later in the season - and less innings = more no decisions
2) Opening Day typically has the "Ace" for both teams which could result in more pitching duels which again could result in more no decisions.
April 1st, 2011 at 3:52 pm
Yawn
April 1st, 2011 at 4:58 pm
my first thought was that it's absolutely extraordinary that one of each isn't much more common. Wow, I guess a really high percentage of games have a decision. Except, why are double no-decisions more common as well?
...
...
And then I realized that these events aren't exactly independent. In fact, they are very very highly correlated.
Yet another lesson in intuitive statistics.
April 1st, 2011 at 5:33 pm
Just out of curiosity, I checked the numbers for Opening Day games. To get a little more data, I went back to 2006 for 5 seasons'-worth of data. There have been 23 Opening Day games in which both starters got no-decisions. There have been 7 games in which one starter got a no-decision. There have been 45 games in which both starters got a decision.
That's 75 total games (which makes sense since there are 30 teams, meaning 15 Opening Day games per year, times 5 years.)
Just out of curiosity, how did you handle the 2008 season? Atlanta opened with that bizarre one game series at Washington, then those two teams went on to play the Pirates and Phillies respectively on the true "Opening Day". Seems to me you would almost have to count 16 games as "openers" that year given that quirk, or just 14 if you struck the two games where the Braves and Nats were actually playing their second game of the season....
April 1st, 2011 at 5:39 pm
Yeah, it does seem like the "double decision case" is a bit high. Last year, of the 4860 games started by starting pitchers, they got decisions 71.8% of the time (1736 W, 1753 L). I guess I wouldn't have expected such a large fraction to be double-decision games but I guess it makes sense.