From d4c55a3da5dbee1d53375ce8c56ca4d1bd18ba0b Mon Sep 17 00:00:00 2001 From: Jay Boice Date: Tue, 3 Jul 2018 11:47:16 -0400 Subject: [PATCH] Add data dictionary for mlb-elo, closes #194 --- mlb-elo/README.md | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/mlb-elo/README.md b/mlb-elo/README.md index 5c26624..e236036 100644 --- a/mlb-elo/README.md +++ b/mlb-elo/README.md @@ -7,3 +7,34 @@ files: This file contains links to the data behind [The Complete History Of MLB](https://projects.fivethirtyeight.com/complete-history-of-mlb/) and our [MLB Predictions](https://projects.fivethirtyeight.com/2018-mlb-predictions/). `mlb_elo.csv` contains game-by-game Elo ratings and forecasts back to 1871. + +The data contains two separate systems for rating teams; the simpler Elo ratings, used for [The Complete History Of MLB](https://projects.fivethirtyeight.com/complete-history-of-mlb/), and the more involved — and confusingly named — "ratings" that are used in our [MLB Predictions](https://projects.fivethirtyeight.com/2018-mlb-predictions/). The main difference is that Elo ratings are reverted to the mean between seasons, while the more involved ratings use preseason team projections from several projection systems and account for starting pitchers. More information can be found in [this article](https://fivethirtyeight.com/features/how-our-mlb-predictions-work/). + +Column | Definition +-----| --------- +date | Date of game +season | Year of season +neutral | Whether game was on a neutral site +playoff | Whether game was in playoffs, and the playoff round if so +team1 | Abbreviation for home team +team2 | Abbreviation for away team +elo1_pre | Home team's Elo rating before the game +elo2_pre | Away team's Elo rating before the game +elo_prob1 | Home team's probability of winning according to Elo ratings +elo_prob2 | Away team's probability of winning according to Elo ratings +elo1_post | Home team's Elo rating after the game +elo2_post | Away team's Elo rating after the game +rating1_pre | Home team's rating before the game +rating2_pre | Away team's rating before the game +pitcher1 | Name of home starting pitcher +pitcher2 | Name of away starting pitcher +pitcher1_rgs | Home starting pitcher's rolling game score before the game +pitcher2_rgs | Away starting pitcher's rolling game score before the game +pitcher1_adj | Home starting pitcher's adjustment to their team's rating +pitcher2_adj | Away starting pitcher's adjustment to their team's rating +rating_prob1 | Home team's probability of winning according to team ratings and starting pitchers +rating_prob2 | Away team's probability of winning according to team ratings and starting pitchers +rating1_post | Home team's rating after the game +rating2_post | Away team's rating after the game +score1 | Home team's score +score2 | Away team's score