Core-five RBI: The frustrating search for a new MLB metric

Mar 19, 2021; Glendale, Arizona, USA; Los Angeles Dodgers infielder Zach McKinstry against the Texas Rangers during a Spring Training game at Camelback Ranch Glendale. Mandatory Credit: Mark J. Rebilas-USA TODAY Sports
Mar 19, 2021; Glendale, Arizona, USA; Los Angeles Dodgers infielder Zach McKinstry against the Texas Rangers during a Spring Training game at Camelback Ranch Glendale. Mandatory Credit: Mark J. Rebilas-USA TODAY Sports
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Mandatory Credit: Kim Klement-USA TODAY Sports
Mandatory Credit: Kim Klement-USA TODAY Sports

How about the True .500 Teams?

A little time was allowed to pass before the .500 teams were selected to examine. This allowed for speculative questions. Would the .500 teams be reasonably close to 0.50 core-five RBI a game per hitter?  What would the average figure be for the .500 teams?

Would that figure deviate from the middling 0.53 Phillies figure for 2021 thus far? If it rose, would the gap between an average .500 team figure and the average first-place team figure be so narrow that the whole study of core-five RBI by itself became meaningless? What were the aggregate first-place figures?

The average for the first-place teams selected on random dates turned out to be 0.583. If the earlier, weeks-long sample for the Dodgers is thrown in (0.70), the core-five figure for each “top” or first-place team’s hitter rises to exactly 0.600.

This means that what could be called Total Core-Five Production (TC5P), or the average number of RBI for the entire core-five group per game, for a first-place team, should be around 3.000.

Up until now we’ve been looking at individual RBI team-leader figures, Core-Five Production (C5P), that generally sub-1.000 figure per player among a team’s top-five RBI men.

The following .500 teams were chosen beginning after play May 16 (Reds) and concluded after play May 26 (Royals).  When there were multiple teams at .500 on a date chosen, the team was selected by coin flip/s (e.g., the Brewers were chosen over the Braves after play May 25).

Six teams were chosen for the sake of equal sample sizes, and for the final team, to reflect the “almost .500” status of the Phillies throughout this project, another “almost .500” team was included.

Team                     C5P

CIN                         0.67 (1)

CHC                        0.55 (0)

MIL                        0.50 (2)

TOR                        0.73 (1)

MIL                        0.46 (1)

KCR (23-24)         0.53 (0)

Crunching these figures, an average 0.573 RBI per game is observed, a “mediocre” team’s core-five RBI production per player (C5P). Adding the earlier snapshot of the Phillies (0.53), like the Dodgers’ weeks-long sample, moves the C5P figure slightly – down to 0.567 for “mediocre” teams (six .500 teams plus the one-game-under-even April Phils).

Again, tentatively speaking, this suggests a .500 team’s core-five group will give you 2.835 runs per game (TC5P) independent of the other team’s defense or pitching.

Clearly, in the early season, “mediocre” teams’ offensive production numbers are a free-for-all. (Oh, and the Blue Jays core-five drives in runs for real.)