3000 Dives, 3000 Hits, and S.J. Gould

In The Flamingo's Smile, a compilation of Gould's articles for Natural History, there is a lengthy discussion of the principle of decreasing variation within established patterns and the disappearance of .400 hitters in baseball. According to Gould the loss of .400 batting average reflects players getting better not worse.  Imagine a range of batting averages whose mean is around .300, a very respectable value. Gould argued in the past that .400 was at the upper extreme of the batting average range. There were also many players who were quite below the average, resulting in a huge variance in batting averages. Over time players got better and converged on the average .300-the variance decreased.  This all means that while currently .400 batting averages are considered unobtainable, there are far fewer players with low batting averages.

Another elite club in baseball is the 3000 hit club.  Currently 26 players have obtained over 3,000 base hits. To hit this mark two things are required, a long career and a great batting average.  A batter hitting 180-233 (a batting average of 0.300 to 0.333) out of the typical 600-700 at bats per year would still require 12-17 seasons.  Most players onlye get 8-10 years in.  For an ROV (remote operated vehicle) to get 3,000 dives it also requires both a long career and a great batting average.  MBARI's ROV Ventana reached that goal this week.  During its 18 years of operation it complete an average of 167 dives per year.  This is a remarkable accomplishment considering that dives are not conducted on weekends, holidays, or in severe weather.  No dives occur on Fridays either allowing for preventitive maintenance and the switching differing tool sleds depending on the research being conducted the following week.  Doing the math, that translates into an over 90% success rate in completion of scheduled dives.  This requires a tremendous effort on part of the ROV pilots and the host vessel's (Pt. Lobos) crew.  For reference, the infamous Alvin, while not a ROV but a manned submersible, has completed just over 4,300 dives in its 40 years of existence.