Team Predictions Through 60 Games
Posted by Charles Mon, 10 Jun 2013 19:52:11 -0400
Filed Under: expected winning pct forecasting predictions science teams
A few days ago the Major League Baseball season passed the 60-game mark more or less. Below is the chart comparing our preseason predictions to current winning percents. As expected, the real world has been converging on our predictions since I last wrote on this topic.
| Team | Pre-Season Win% | June 5 Win% | Act. - Pre. |
|---|---|---|---|
| New York Yankees | 0.526 | 0.576 | 0.050 |
| Tampa Bay Rays | 0.564 | 0.552 | -0.012 |
| Boston Red Sox | 0.511 | 0.600 | 0.089 |
| Toronto Blue Jays | 0.554 | 0.424 | -0.130 |
| Baltimore Orioles | 0.464 | 0.559 | 0.095 |
| Detroit Tigers | 0.580 | 0.544 | -0.036 |
| Chicago White Sox | 0.502 | 0.439 | -0.063 |
| Kansas City Royals | 0.456 | 0.429 | -0.027 |
| Cleveland Indians | 0.418 | 0.508 | 0.090 |
| Minnesota Twins | 0.437 | 0.464 | 0.027 |
| Texas Rangers | 0.519 | 0.621 | 0.102 |
| Oakland Athletics | 0.557 | 0.590 | 0.033 |
| Anaheim Angels | 0.566 | 0.433 | -0.133 |
| Seattle Mariners | 0.465 | 0.433 | -0.032 |
| Houston Astros | 0.378 | 0.367 | -0.011 |
| Atlanta Braves | 0.585 | 0.627 | 0.042 |
| Washington Nationals | 0.558 | 0.492 | -0.066 |
| Philadelphia Phillies | 0.538 | 0.500 | -0.038 |
| New York Mets | 0.451 | 0.411 | -0.040 |
| Miami Marlins | 0.398 | 0.267 | -0.131 |
| St. Louis Cardinals | 0.534 | 0.644 | 0.110 |
| Cincinnati Reds | 0.537 | 0.600 | 0.063 |
| Milwaukee Brewers | 0.531 | 0.379 | -0.152 |
| Pittsburgh Pirates | 0.429 | 0.583 | 0.154 |
| Chicago Cubs | 0.408 | 0.421 | 0.013 |
| Arizona Diamondbacks | 0.564 | 0.576 | 0.012 |
| San Francisco Giants | 0.507 | 0.525 | 0.018 |
| Los Angeles Dodgers | 0.524 | 0.431 | -0.093 |
| San Diego Padres | 0.492 | 0.458 | -0.034 |
| Colorado Rockies | 0.445 | 0.533 | 0.088 |
As with all tables in this series, this table is sortable. Clicking on the heading of a column will sort the table by the values in that column, ascending or descending on alternating clicks.
Our predictions are off by an average of 6.6 percent per-team or about 10.7 games over the course of a season. We were off by about 13.2 games per-team per season on 16 May at the 40-game mark. We are doing better at this point that we were through 60 games in 2012
The convergence of predictions to results is related to the meaningfulness of results. Many fans don't give much care to the standings until deep into the season. They are waiting for the noise of small sample sizes (SSS) to die out. SSS are our enemy. Our predictions improve as the noise dies out. A future post will measure when this happens. The question to be answered is at what date does winning percent through that date say something meaningful about winning percent after that date. That date will be helpful for fans who want to know when exactly is a good time to start checking the standings. If you check the standings during spring training I can't help you.