Analysis
The numbers behind the season
Ten studies, each asking one question of the 720 games played so far and the four seasons in the record book. Every number is computed when the page is requested, so the findings move as the season does — and every one comes with the thing most baseball writing leaves out: how sure we are.
Each study opens with its finding in plain language, then the chart, then the method, then what could make it wrong. Where ten clubs or a few dozen players is all there is, the page says so.
Studies
Ten questions, with intervals
Fitting the KBO's Pythagorean exponent
Bill James squared runs to predict wins. The game log lets us fit the exponent this league actually uses.
What scores runs: OBP or SLG?
Thirty-odd team seasons across four eras, one regression, and the old Moneyball question with error bars.
Signal and noise: when a rate starts to mean something
How many plate appearances before a strikeout rate is half talent? The league's own spread answers it, and tells us how hard to shrink every number toward the mean.
ERA minus FIP: luck, skill, or the fielders?
The gap between what a pitcher allowed and what his strikeouts, walks and home runs say he should have. A funnel shows how much of it is noise; last season shows how much carries over.
One-run games and blowouts
Clubs with great records in close games are said to know how to win. A chi-square test asks whether those records spread any wider than coin flips.
How big is home field in the KBO?
Every final this season, split by who batted last. The league-wide edge, each club's home-road gap, and whether those gaps differ by more than chance.
Are clubs streaky?
A runs test on every club's win-loss sequence, and two thousand shuffled seasons to see how long a streak chance alone produces.
When do KBO players peak?
Birth dates from the record centre against wRC+ and FIP — once as a snapshot, once as the same player a year apart, which is the only honest way to do it.
Form, and how much of it is real
Each club's season as a rolling ten-game run differential, month by month, and a split-half test of how much of the table is talent.
Four seasons, four run environments
2003, 2010, 2025 and this season side by side: how offence has moved, and whether the gap between the league's best and worst hitters has narrowed.
Reading an interval
A 95% interval is the range of answers the data cannot rule out. When it is wide, the honest finding is that we do not know yet.
Reading a p-value
How often chance alone would produce a pattern at least this strong. Run twenty tests and one will clear 0.05 by luck, so the studies count their tests.
Reading r²
The share of the spread a model accounts for. With ten clubs, a high r² can still be fragile; the intervals say how fragile.
Record book updated Oct 13, 2026; game log Oct 13, 2026; biographies Oct 13, 2026. No park factors: the KBO does not publish runs by venue, so park effects sit inside every club and player figure here. The standings, player and lab pages carry the season's descriptive numbers; these pages are about how far those numbers can be trusted.