The Leadoff Walk by plen September 15, 2010 We’ve all heard a broadcaster comment on the impending doom of a leadoff walk and yet they fail to seem to apply the same sort of fateful outcome for a single. I thought it would be interesting to find the outcomes of each of the ways a player can leadoff an inning by getting on first base and see if it affects whether or not the runner goes on to score. I took the retrosheet data sine 1952 (but not including this year) that I have as a MySQL database and created a quick python script to determine these results. I took it further and examined if the breakdown were any different in late game situations, as I’m always hearing “You never want to walk the leadoff batter but especially late in close ball games”. I was also curious if even in general more solitary runs get manufactured once a leadoff runner gets on base in late game situations. Total times batter lead off an inning by getting to first: 508312 Total times runner scored: 192150 So a leadoff batter who starts on first base scores 37.80% percent of the time, here is the breakdown via the means they get aboard Any inning Single 325455 Scored 122662 37.69% Walk 150570 Scored 57189 37.98% HBP 11865 Scored 4600 38.77% Error 19260 Scored 7270 37.74% Strikeout 1007 Scored 375 37.24% Catcher's Int. 155 Scored 54 34.84% Totals 508312 Scored 192150 37.80% So it appears as though it’s not much of a statistically significant difference between the walk and the single. The HBP numbers seems to be a bit of an outlier, I’m wondering if that is just sample size or if such an outcome rattles the pitcher to the point of that much more runs being produced. Lets now examine the breakdown based upon the stage of the game. 6th inning or earlier Single 217421 Scored 83243 38.29% Walk 100587 Scored 38798 38.57% HBP 7879 Scored 3070 38.96% Error 12778 Scored 4880 38.19% Strikeout 645 Scored 244 37.83% Catcher's Int. 107 Scored 36 33.64% Totals 339417 Scored 130271 38.38% 7th inning or later Single 108034 Scored 39419 36.49% Walk 49983 Scored 18391 36.79% HBP 3986 Scored 1530 38.38% Error 6482 Scored 2390 36.97% Strikeout 362 Scored 131 36.19% Catcher's Int. 48 Scored 18 37.50% Totals 168895 Scored 61879 36.64% Interesting how 1.74% more leadoff runners reaching first score in the earlier innings. Is this a comment on the failure of manufacturing runs or pitching being different in the later stages of the game? Perhaps a deeper look based upon “close game situations” is in order for that.