How the Final Score Can Lie: Rating “Score Control”

(hint: Duke’s stunning 23-point comeback at Louisville was among the biggest deficits overcome, but not #1!)How much time did Wofford spend leading in each of its games?In how many games did Gonzaga trail for more than 50% of game time?But back to our Score Control metric.

We are interested in the average in-game point difference (“AvgPtDiff” field), which gives us a summary of the team’s scoring margin throughout the game.

To study this more and build the team season-level metric, we read the team game-level data into Colab.

We generated the following plot to see if this average in-game point margin tells us anything different than the final point margin on a game level, using plotly in Colab.

There’s a strong correlation between final margin and in-game margin (as we’d expect), but still a good deal of variation across games with the same final margin.

Let’s zoom in further on the plot above to look only at games where a team won by 1–9 points.

For these final score margins, we can see average in-game margins from as low as -10 to more than +15.

As we saw with the Villanova example earlier, all 6-point wins are not created equally!From this game-level metric, we can aggregate to get the average in-game point differential for a team across all its games in the season.

You can see that on the season-level in-game score metrics page of our dashboard, with a screenshot of the top 10 teams below (numbers through Tuesday’s games).

Top 10 Teams in Average In-Game Point DifferentialGonzaga is dominant, nearly four points ahead of every other team!.The Bulldogs have spent more than half their season leading by double digits, and have had a lead of 20+ points at some point in two-thirds of their games.

The teams ranked behind them are interesting: a mix of other top NCAA Tournament seeds (like Duke and Virginia), as well as some teams who dominated their lower-level conferences (including Lipscomb, who didn’t even make the tournament).

If you followed our work from last week, the next step based on this initial list might be predictable: schedule adjustment.

While Lipscomb may have a higher average in-game point differential than Duke, it’s clear statistically — and from a basketball standpoint — that the Blue Devils played a much tougher schedule than the Bisons.

Comparing their raw numbers can be a bit misleading if used for rating the teams from an overall quality standpoint.

So to get to our final Score Control metric, we use the game-level average in-game point differential data, and adjust for opponent and site using ridge regression (see the post linked above for much more detail).

We’ve shared these ratings and rankings on the BracketIQ Metrics page of our public-facing dashboard (along with our other BracketIQ metrics, some of which we’ll explain in more depth during the tournament).

Here’s the top 10 (through Tuesday):Top 10 Teams in Score ControlGonzaga is still #1 in the adjusted version of our metric, but the distance to other teams is much smaller.

We see Duke, Virginia, and Michigan all moving up from their spots on the previous list, and they’re now joined by some of the more successful programs (and top NCAA Tournament seeds) rather than mid-majors who dominated smaller conferences.

In fact, the top seven teams in Score Control are all 1- or 2-seeds.

While not a be-all and end-all, this certainly makes us feel better about the metric’s ability to measure overall team quality.

But still, can we learn something from Score Control that we can’t otherwise learn from just looking at a team’s average final point margin?.To study this, we plotted those two quantities for the 68 teams that qualified for the 2019 NCAA Tournament in the following interactive plot.

The diagonal line is the “expected” Score Control given a team’s average final point margin — basically, where every team would lie if the two metrics rated them nearly identically.

We can see some teams pretty far off the line, which suggests that looking at in-game point margin and adjusting for schedule can make a big difference.

As an example, VCU and UCF — two teams that face off in the Round of 64 on Friday — see their rankings improve more than 10 spots when going from average point margin to Score Control.

On the other hand, both New Mexico State and Liberty rank in the top 15 when only looking at final scores, but are dozens of spots lower when looking at the evolution of their scores within games and accounting for schedule.

Now that we’ve made the case for the importance of following the score throughout games in rating team quality, hopefully it’ll help frame the many, many hours of college basketball you’ll watch in the next few days.

Come back to this dashboard throughout the tournament to see Score Control and other in-game scoring metrics.

Enjoy the Madness!.

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