League Rule Changes - Comparing player stats from different eras

JolleyWrencher

The thread about Stockton = Trout has been interesting. Griffey vs Trout became a major point to discuss.

I began thinking, pretty dangerous, about other things to impact a player. Like playing the playoffs with the flu, learning your father passed away, birth of a child planned, rule changes, etc.

I'm curious how often rule changes are considered when comparing stats. Maybe RBIs go down, or up, across the entire league and the overall change should be weighted and taken into account, on a per stat basis, for comparing people like Griffey to Trout.

I just pulled off the MLB rule changes since Griffey Jr entered and I'd be surprised if the rules changes weren't used already in the discussions. Website for reference.

https://www.baseball-almanac.com/rulechng.shtml

2008 MLB adds limited (home run calls, fair or foul) instant replay to be in effect for all games starting on Friday, August 29th.
2014 Runner attempting to score may not deviate from his direct pathway to the plate in order to initiate contact with the catcher (or other player covering home plate). Catcher cannot block plate without possession of ball.
2016 Slides on potential double plays will require that base runners must make a bona fide attempt to reach and remain on base.
2020 Pitcher must face a minimum of three batters in an appearance or pitch to the end of a half-inning.
Temporary / COVID-19 Pandemic Rules Added for Shortened Season:
Extra-inning runner on second base automatically.
Seven-inning doubleheaders.
The postseason expands to 16 teams.
Universal designated hitter.
2022 Draft lottery implemented to discourage tanking.
The National League officialy adopts the designated hitter.
The postseason expands to 12 teams.
2023 Bases increase in size from 15 to 18 inches.
Defensive shifts are banned.
Extra-inning runner on second base, from 2020 temporary rules, made permanant.
Pitch clocks will be used.

I haven't kept up on NBA, NHL, or USL rule changes but I know NFL surely makes big changes which must make stat comparisons more subjective. Extra games, play clocks,

Take this thread where you want to. I wanted to spark a discussion and maybe put a few more variables into the mix.

daltex

Which is why any meaningful stats attempt to correct for eras (and even parks in baseball, basketball not so much). It's inevitable to compare players to their peers, which means that the top pitchers will appear to be 19th century guys, and, if you restrict it to the 20th century, then the list is dominated by guys who pitched most between 1900 and 1920. Still, it's hard to compare our current era, where only eight pitchers pitched 200 innings in 2022 and, say, Charley Radbourn's day where he pitched 632⅓ innings in 1883 and followed it up with 678⅔ the next year. He won 108 games over that span, and didn't even lead the league in 1883.

Be skeptical of any stats that can be calculated by a fourth grader with a four function calculator.

Basebal21

Theyve all made massive changes designed to increase offense with everything from the 3 point line in the NBA to smaller creases and no play zones in the NHL to MLB now shortening the distances between bases. MLB for example base stealing numbers have to have a hard line now from the old distance and now.

As far as judging players from different eras the first thing that needs to happen is take the era into account. This is more of an issue with sports other than baseball since the NBA didnt have a 3 point line, NHL and NFL was much more psychical etc. Aside from the start of the sports in the 1800s the best athletes in those sports would still be the best today if they were born today.

Ironically baseball even with all the changes is the one aside from pitching where old time offensive production still holds up and is very impressive. I take out pitching because the the Cy Young 500+ wins and things like that will never be sniffed again but Babe Ruth still has offensive records that still havent been broken.

Everything has to be taken in consideration when judging any player