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Simple Projection System

The Simple Projection System (SPS) is just that: simple. The SPS is very similar to baseball's Marcel the Monkey Forecasting System. Marcel's keeper, Tom Tango, describes the system as follows:

"[I]t is the most basic forecasting system you can have, that uses as little intelligence as possible. So, that's the allusion to the monkey."

Let's see: basic, little intelligence, monkeys...I like it. I took Tom's general idea, tweaked it to apply to basketball and, presto, the SPS. Before I go through the methodology, let me state up front that I would not stake my reputation on these results. These projections are being published because (1) they were easy and (2) they were fun. That said, I do believe these results will hold up quite well when compared at the end of the season with other, much more sophisticated projection systems.

Now that the caveats are out of the way, let me walk you through the method using Dwight Howard's rebounding as an example:

  1. Give the 2007-08 season a weight of 5, the 2006-07 season a weight of 4, and the 2005-06 season a weight of 3 and calculate the weighted sum of minutes played. The last three seasons Howard has played 3088, 3023, 3021 minutes, so his weighted sum is 5 * 3088 + 4 * 3023 + 3 * 3021 = 36595 minutes played.
  2. Use the same weights as above and calculate the weighted sum of rebounds. The last three seasons Howard has grabbed 1161, 1008, and 1022 rebounds, so his weighted sum is 5 * 1161 + 4 * 1008 + 3 * 1022 = 12903 rebounds.
  3. Calculate the weighted sum of rebounds for a league average player playing Howard's minutes, then scale this figure to 5000 minutes. The weighted sum for a league average player playing these minutes is 5 * 3088 * (103271 / 594100) + 4 * 3023 * (100992 / 595750) + 3 * 3021 * (100754 / 595550) = 6267 rebounds. Scaled to 5000 minutes this is 5000 * (6267 / 36595) = 856.2645 rebounds.
  4. Calculate the player's projected per-36 minute value. To do this we will find the sum of (2) and (3), divide by the sum of (1) and 5000, and multiply by 36: (12903 + 856.2645) / (36595 + 5000) * 36 = 11.9085 rebounds per 36 minutes.
  5. Calculate and apply the age adjustment. If the player is younger than 27, then the age adjustment is equal to (27 - age) * 0.005. If the player is older than 27, then the adjustment is equal to (27 - age) * 0.01. Howard's 2008-09 season will be his age 23 season, so his age adjustment is (27 - 23) * 0.005 = 0.02. Applying this to the figure in (4) we get (1 + 0.02) * 11.9085 = 12.1 rebounds per 36 minutes.

A few more notes regarding the SPS: