Predicting MLB Team Performance

Every year you see tons of websites predicting which MLB teams have made the right moves to get their team to the playoffs. Some make their predictions based upon their inane baseball IQ. Others use a popularity approach, which teams are getting the most press or the teams that have landed the big name free agents. Perhaps some sites use dart boards or drawing names from a hat. How else can you explain sites that predict the Cubs or Astros getting to the playoffs! Well, we are going to take a little different approach.

Bill James, the pioneer of baseball sabermetrics, created a formula to predict a team’s winning percentage called “The Pythagorean Expectation”. Without boring everyone with the fine details, this formula models the winning percentage of a team based upon runs scored and runs allowed. With anticipated starting and reserve lineups, MORPS has already projected runs created and runs allowed for each team in order to create individual projections. By feeding this data into a refined version of Bill James’ formula created by David Smyth, MORPS team win/loss records can be projected. The records are then adjusted slightly to show the number of games played within each division, league and inter-league matchups.  This adds an element of anticipated strength of schedule to a set of formulas created to model the past rather than predict the future.

In the next few days/weeks, I will plan on releasing projected wins and losses for the teams in MLB. I was hoping that all the big name free agents would be off the board at this point, but progress can’t wait on hard-headed agents or budget conscious General Managers. Since my main goal leading up to spring training is to continue updating MORPS for upcoming fantasy drafts, I will begin releasing team projections very soon. When final free agents sign contracts, projected wins and losses may adjust slightly. I may go back and update team projections prior to the start of the season if time permits.

For those that are interested in the detail, I have outlined several the formulas below that are used in team win/loss projections.

The Pythagorean Expectation (developed by Bill James)

Pythagenpat formula (developed by David Smyth)

Exponent = ((r + ra)/g)0.287

Runs Created (developed by Bill James) – calculated for each individual player


  1. Pingback: 2013 MORPS Team Projections « Major-League Obie Role-Based Projection System
  2. Pingback: 2014 MORPS Team Projections « Major-League Obie Role-Based Projection System
  3. Pingback: 2015 MORPS Team Projections « Major-League Obie Role-Based Projection System
  4. Pingback: 2016 MORPS Team Projections « Major-League Obie Role-Based Projection System

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