Do Leadoff Walks Lead To More Runs?

Tim McCarver, during a playoff game in 2002:

The one thing I would tell a young pitcher is never walk the leadoff man. He always scores; he always scores.

David Smith, the man who started and runs Retrosheet, thought he would check that out (though, obviously, a leadoff batter who walks does not always score). Smith looked at 29 years (1974-2002) worth of data: 61,365 games, 1,101,019 half-innings, more than 4.5 million plate appearances.

     Reached   Scored  Frequency
BB    82,637   33,002    39.9%
1B   183,468   72,841    39.7%
2B    48,364   30,961    64.0&
3B     6,573    5,753    87.5%
HR    27,205   27,205   100.0%
HBP    6,217    2,543    40.9%
E     12,105    5,298    43.8%

A leadoff batter who walks does not score at a significantly higher rate (statistically speaking) than a leadoff hitter who singles.

In August 2006, McCarver said:

There is nothing that opens up big innings any more than a leadoff walk. Leadoff home runs don't do it.* Leadoff singles, maybe. But a leadoff walk. It changes the mindset of a pitcher. Since he walked the first hitter, now all of a sudden he wants to find the fatter part of the plate with the succeeding hitters. And that could make for a big inning.

* - Sorry, Tim.

     Leadoff    0R       1R      2R      3R     4R      5R    6+R
1B   183,468  104,074  35,868  22,726  11,329  5,375  2,415  1,681
BB    82,637   46,794  15,837  10,481   5,167  2,503  1,100    755

The percentages for that chart:

     Leadoff    0R    1R    2R    3R   4R   5R  6+R
1B   183,468   56.7  19.6  12.4  6.1  2.9  1.3  0.9
BB    82,637   56.6  19.2  12.7  6.2  3.0  1.3  0.9

Whether a leadoff batter singles or walks has no correlation with how many runs his team will eventually score in that inning.

Smith, from The Baseball Research Journal 35 (2006):

[A]necdotal observations and gut feelings are just that and have no inherent credibility, no matter what the source. Since we can now check these opinions with evidence, and McCarver definitely has at his disposal the talents of people who can do such checking, then we should expect him and other announcers to get it right.

It is not only McCarver. In May 2008, Blue Jays announcer Rance Mulliniks estimated that a leadoff walk comes around to score 60-65% of the time. But why estimate when the facts are available with a little bit of effort (even as little as asking an assistant to do some research)?

More recently, plen had a similar post at Fangraphs in September. Looking at the data from 1952-2009:

      Leadoff   Scored   Frequency

1B    325,455  122,662     37.69%
BB    150,570   57,189     37.98%
HBP    11,865    4,600     38.77%
E      19,260    7,270     37.74%

Again, leadoff singles and leadoff walks come around to score at the exact same rate, statistically speaking.

Richard Griffin of the Toronto Star has a lengthy Q&A with Blue Jays manager John Farrell.