How did we do? CJSR’s preseason predictions for how many wins would get teams in the playoffs largely held true

Before the season started, we used the state’s Strength Index formula and the 2019 playoff brackets to determine how many wins a team would need to guarantee they would get in the playoffs. We wanted to see if previous results could tell us anything about goals for 2021.

And we were nearly right on the money.

First, the math:

We did this by looking at the highest OSI among teams that missed the playoffs in each section, figuring the minimum should be at some point above that. (If the highest OSI team to miss the playoffs had an OSI of 35, and the next team above that in the playoffs was a 36.41, that would be the minimum.)

Then, we calculated preseason strength of schedule, or the maximum OSI a team could get if it went undefeated, as well as the minimum OSI a team could get if it went without a single win. We divided the difference by the number of games played to figure approximately how many OSI points each game was worth, and how many wins it would take to get an OSI over the minimum to make the playoffs.

Inotherwords, if a team’s maximum OSI was a 60, the minimum was 30, and the worst they could do was a 40 without missing the playoffs, how many wins would it take to get to that point? (If they played eight games, the answer would be three, which would get them to 41.75, but we wanted as close to a guarantee, so we made it one additional game, and would say that team needed to win four games to guarantee a playoff berth – by our projections.

For example, we projected North Brunswick would have to win four games to make the playoffs. They won six and got in. We said Plainfield would have to win five to guarantee a playoff berth. They won four, and finished 17th, one spot out of the postseason.

Out of 58 public school teams in the Big Central (both non-publics automatically qualified, though St. Joseph-Metuchen opted out) we were right on with 53 of them, although two were on a technicality. So, really, we were only off on three of 58. That’s 95 percent!

First, the pleasant surprises:

Bound Brook made it with 4 wins on the strength of a big Week 9 win over Roselle, despite our prediction they would need at least five, six to guarantee a spot. And Middlesex got in with just three wins; we thought they would need four, with five as a guarantee.

Some of that can change, of course, because opponent SI values fluctuate throughout the season. But we think the data shows that, by-and-large, some teams go up, others go down, and it mostly balances out in the end.

The one team that didn’t make the playoffs despite exceeding our prediction was North Plainfield. We figured they’d need four wins to get in, five as a guarantee. They got six and missed out by one spot in North 3.

The two “technicalities” were Scotch Plains-Fanwood and Montgomery.

SPF finished 13th in the standings, reaching our minimum win goal, and would have made the playoffs if not for four ejections in a Week 2 game against Plainfield that rendered them ineligible for the postseason.

Montgomery won three games, and would have been out (we predicted four, or five for a guarantee) but only made it as the 17th team because Scotch Plains-Fanwood was out.

Had it not been for the technicality, based on pure standings, we were right on those.

The Big Central would be wise to use this data as a component of scheduling. Some teams, we projected, only needed to win two or three games to get in the playoffs, while some would have needed six or seven. What happened to those teams?

One one hand, you have a team like Dayton, which would have needed to win six or seven won only three, and was nowhere near the playoffs.

Then, there’s a team like Manville. Their schedule was so “easy,” according to the state formula for Strength Index, they would have had to win eight or nine games to get into the postseason. They wound up losing a game due to flooding from Ida, and in the end, finished 6-2, missing the playoffs. by one spot.

Interestingly enough, New Egypt from down in Burlington County also was 6-1 heading into Week 9. While Manville lost to Metuchen, New Egypt beat Robbinsville to finish 7-1, and jump all the way into tenth in the playoff standings.

The bottom line to learn from this data is: A team that has to win eight games to make the playoffs has too easy a schedule. A team that only has to win two probably has it too easy.

Somewhere in the middle, we believe, is the sweet spot.

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