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Unless Derek Jeter suffers a season ending injury, he will collect his 3000th career hit sometime during the 2011 season. Before opening day, Mike Vaccaro of the NY Post thought it would happen around June 7th based on Jeter’s historical average of 1.27 hits per game. Through the first 16 games of 2011, Jeter had collected 14 hits, an average of 0.875 hits per game. Based on his historical average he should have had closer to 19 hits. If he all of a sudden sticks to his historical average from this point on, hit 3000 will occur on June 11th.

Jeter’s career statistics are available on-line and computing his average hits per game by month shows some variance:

So while it seems highly likely Jeter will reach 3000 hits sometime in June, the fact that he produces 7% more hits per game in the months of July and August as compared to March+April and May may suggest using his career average hits per game will yield too early of a date in June.

Breaking down the month-to-month performance down by season doesn’t show a very strong correlation e.g. it’s hard to predict how Jeter will perform in May based on his April statistics (red cells highlight an instance where May was less than March+April).

In 9 out of 15 seasons, he had a lower hits per game ratio in May as compared to March+April. In only two seasons did he have a hits per game ratio < 1 and in one of those seasons his hits per game was lower in May. Attempting a linear regression on these numbers yields May Hits Per Game = 0.9046 * April Hits Per Game + 0.2651 however, the R-square for this is 0.06018 (closer to one is better), indicating little predictability. Here’s a scatter-plot showing the results are…scattered (red is the linear regression and blue is the LOWESS).

Perhaps recent performance is more indicative of what can be expected in the future. In 4 of the last 5 years Jeter’s hits per game in May was lower than the corresponding hits March+April. However, his average March+April hits per game was also higher over the last 5 years (1.36 vs 1.24). His average May hits per game over the last 5 years is 1.25 which is pretty close to his overall average of 1.23, so it might make sense to just use his overall historical average to predict his hits in May.

If he gets back on track and averages 1.24 hits per game in the final 9 games of April and 1.23 hits per game through the 29 games in May, he will begin June with 2987 hits. Using his June average of 1.26 hits per game, he will collect his 3000 hit during the 10th (Sunday June 12th) or 11th (Monday June 13th) game of the month, a day or two later than using his overall historical average.

Clearly there are many other factors e.g. rain outs, injury, increasing pressure to hit as the milestone draws closer etc. which make predicting the exact game nearly impossible. If Jeter were at 2999 hits during a road trip, it’s unlikely he would purposefully go 0 for X until the next homestand. That said, the Yankees will be playing at home June 7th – June 16th, and due to Jeter’s slow start it seems unlikely he’d reach 3000 hits before then. If he manages to get back on track then that 10 game stretch, in addition to featuring games against the longtime rival Red Sox and new found enemy Rangers, could be extra special.