It has been a little over two weeks since Part 2 of this series so let’s take a look at where the playoff horse race stands a little over 1/3 into the 2019 season.
The table below is the same as before except it is sorted by the only stat the MLB commissioner cares about, team WAA, team wins minus losses. Sorting on Total WAA value according to this data model is good for career tabulations spanning many years but not for current year.
Teams in bold are leading their divisions and the rest of these teams are in the Wild Card hunt as well as their own divisions. In theory Total WAA as estimated by this data model should equal their team WAA in the WAA column. They don’t for the following reasons.
- Pythagorean Expectation (PE) used to estimate WAA is not completely accurate. It is an estimation based upon run differential and many teams will be higher of lower than what PE estimates. Real life is correct, the estimate is not correct. Many sites claim that PE calculation represents what a team should have which is incorrect. It only indicates whether a team is efficient or inefficient with the runs they score. Why that is is fodder for arguments at the pub, not for a data model.
- Injuries: The above is based on current 25 man rosters. High value players who get injured, who brought their teams wins before their injury, fall off the list reducing Total WAA. This model does not keep track of injuries or 40 man rosters.
- Replacement Players/Trades: As a season progresses bad players get replaced by new guys from minors or trades. WAA for bad players goes off the books and if they trade for a good player, positive value will go onto the books where Total WAA can exceed a team’s real WAA. This will become more apparent later in the season — especially as playoff season approaches when contenders stock up for the final stretch to win a World Series.
Color coding of the above table will be automated in the next part. This is a Keep It Simple Stupid (KISS) model that avoids publishing large tables with a lot of numbers. There really is no other way to properly present this model data and hopefully color coding will make it easier to read.
All columns above are WAA, wins minus losses numbers. The UR column is Unearned Runs Above Average which has been described over and over here. It shows Atlanta (ATL) has the worst UR of the top 15 teams. UR this bad usually comes back to haunt that team unless they improve by the end of the season. HOU and COL have the best UR of the top 15 teams.
That is all for now. Cubs start another series with SLN Friday so we’ll look into what the Cardinals have been up to. Until then ….