Purdue Season Review

With the conclusion of Purdue's season it is time to do a comprehensive review. Using SportsCode output reports and data I've coded, I'm going to look at team trends, shooting patterns, line-up construction, players of interest, and player comparisons.

Purdue Season Review Report with 'Basic' boxscore and Purdue shooting charts

Team Trends

Purdue started the year running their traditional offence: screen-the-screener actions, creating space in the post for Williams iso plays, springing Stefanovic open for threes, etc. They recruit to a system and their players fit stereotypes established by previous classes, e.g. - Dakota Mathias to Sasha Stefanovic, or Isaac Haas to Zach Edey. However, because of injuries, like that of Stefanovic, and the unexpected development of their freshmen, Purdue seemed to incorporate more modern-style offensive actions, i.e. - Ivey-Williams pick and rolls. This sparked a very strong end-of-season run and pointed to a bright future for the programme.

Analysing Purdue's season review window from a team perspective is rather anti-climatic. For a winning team nothing seems extraordinary. They rebounded better, were more efficient shooting, and had more attempts than their opposition. They averaged the same amount of points-per possession than the opposition (0.81) but also averaged 5 more possessions and hence won games by approximately 4 points. I would have predicted better shooting from three considering the attention given to the centres and the ability of Stefanovic, yet the team shot 32.9% from behind the perimeter and 34.3% from catch and shoot attempts alone. However, 25% of their points still came from catch and shoot threes, followed predictably by post ups (16%), where Purdue scored 1 point-per shot attempt.

E: [email protected] 1 P: 380 900 1460 Defensively, Purdue's opposition relied heavily on threes with 36% of their total attempts coming from catch and shoot opportunities. Despite the volume, or because of it, they weren't efficient shooting 31.5% overall from three and only 32.8% from catch and shoots for 0.98 points-per attempt. The next highest frequency came from shots off the dribble. These weren't efficient shots, only 31.6% went in, but were also the source of Purdue's worst defeat of the season against Rutgers. Understandably, only 6% of opposition attempts were post ups despite being in a centre-dominated conference. However, they were equally as efficient as Purdue, scoring 1 point-per attempt.

Purdue Season Review Report with 'Advanced' boxscore and Opposition shooting charts

Freshmen Analysis

I'm going to look at Edey more in-depth further down, but I want to do a focussed analysis of Purdue's other acclaimed freshmen: Ivey, Gillis and Newman. Per-game, Ivey averaged 11.1/3/1.7 with 1.3 turnovers and shooting 39.4% from the field and 26% from three. These are impressive figures for a freshman, however, the advanced numbers tell a more concerning story: he's only one of two players - the other being Morton - with a negative plus- minus at -11; he also has the worst points-above replacement on defence figure at +0.07, meaning the opposition scored 0.07 points more per-possession when Ivey was on the floor. He also just needs to get better from range. He's an inefficient spot-up shooter despite a heavy volume of shots from the category, with an efficiency of 26.6% from catch and shoot threes, including going 28.6% from uncontested attempts. Ivey is best attacking the rim. On drives Ivey shot 54.2%, and if he was to improve his assists-per game, he could become a scary distributer off high ball-screens with a threat to dunk.

Gillis has the second best plus-minus on the team at +98 despite the lack of flashy numbers to explain it. He went 5.2/4.4/1.3 per game, shooting 47.4% from the field. He's a net-even presence on defence but a positive of offence with his ability to cut and improved three-point shooting not evident in the 34.5% efficiency number. Newman is Purdue's most frustrating freshman. In some games, like against Minnesota, he is Lebron James, but in others he is seemingly invisible. He's a good defender (-0.03 PaR-D) and a net-even on offence. A better three- point shooter than his 37.4% efficiency suggests, he is currently a 3-and-D player with a really high ceiling.

E: [email protected] 2 P: 380 900 1460 Williams vs. Edey

Player comparison chart for Edey and Williams The most interesting analytical approach to Purdue was the personnel comparison of Williams and Edey. Per-40 minutes, the counting stats favour Williams who went 24.2/14.5/3.2 compared to Edey who went 22.8/12.4/0.9. However, the advanced stats prefer Edey, who had a points-above replacement on offence of +0.02, while Williams was a net-negative offensive player at -0.01. Edey also had a better plus-minus of +83 compared to +54 for Williams. Why is there such a discrepancy between the counting and advanced stats?

Firstly, Williams played against opposition starters. Secondly, though they operate in the same offensive system, they act very differently within it. When Williams is on the floor, the offence starts with him; whereas when Edey is on the floor, the offence ends with him. You can see this discrepancy in their usage rates: 34.1% for Williams, the highest on the team, versus 27.6% for Edey. Williams takes 22.8% of the teams shots while Edey only takes 9.4%. This is noticeable when you watch Purdue. Williams likes to iso on the left or right , stop the offence, and either post up or look for cutters and open shooters (like he did against Ohio State). Edey, on the other hand, is almost exclusively a finisher. He rarely dribbles, instead waits for the ball to come to him in advantageous positions to score. This is evident in their respective shot charts. Edey has a very limited menu, with 91% of all his attempts coming as either post ups, cuts or putbacks; but what makes him especially different to Williams is where these shots occur: 71% of Edey's shots come at the rim compared to 52% for Williams, who takes shots from further out in the paint, in the left and right block and from the elbows. And to compare their most shared category, post ups, Edey scores 1.04 points-per post up attempt, while Williams scores 0.98 points-per post up attempt. Edey, who has has better effective- and true-shooting numbers, is the more efficient shooter.

The final point of comparison is how the team performs when either is on the court. This is made easier by Purdue's binary substitution structure - neither was ever on the floor with the other. Surprisingly, per-100 possessions, Purdue is -0.9 when Williams is on the floor but +1.8 with Edey. When Williams is on the floor, Purdue scores 0.8 points-per possession, but 0.83 with Edey. In fact, when Edey is on the floor, Purdue shoots...

E: [email protected] 3 P: 380 900 1460 better from both three and two, and even has more assists. On defence, with Edey, Purdue forces a lower two- point shooting percentage, and blocks more shots; however, both Williams and Edey allow the same amount of points on defence (0.81 per-possession). The data suggests Purdue is a better team with Edey, hypothetically because of increased ball movement and a larger percentage of shots in higher efficiency areas.

Line-up Analysis

Line-up charts for Purdue's starting line-up (left) and the line-up with Williams swapped out for Edey Purdue's starting line-up changed from the start of the season to the group they finished with of Hunter Jr, Ivey, Stefanovic, Gillis and Williams. Per-100 possessions, this group is +2.3. The starting line-up isn't Purdue's best shooting group, and isn't the best defensive combination either. They do, however, well. My personal favourite line-up, the same starting group with Williams swapped out for Edey, is apparently terrible. Though based on a limited sample size, per-100 possessions this Edey line-up is -17.1. They are a better offensive group, especially in the half-court, than the starting group, scoring 0.83 points-per possession on 51.3% shooting, but are terrible defensively, allowing 1 point-per possession on 53.7% shooting.

Another line-up of interest was the 'all freshman' line-up, consisting of the only non-freshman Hunter Jr at point- guard, along with Ivey, Newman, Gillis and Edey. This group per-100 possessions was +0.5 on a limited sample size of approximately 31 minutes of game time. They were efficient offensively, scoring 0.84 points-per possession on 50% shooting, but were poor at rebounding and weak defensively, allowing 0.83 points-per possession. But considering the youth and their collective growth, this group should only get better, especially if Newman becomes more consistent and Ivey gets more efficient.

The last group I'll mention is a hypothetical second-unit line-up consisting of Thompson, Ivey, Stefanovic, Wheeler and Edey. From a small sample size of approximately 26 minutes, per-100 possessions this group is +28.7! They shot 56.8% from the field and 46.2% from three, and allowed only 0.7 points-per possession on defence. This whole group returns next year.

E: [email protected] 4 P: 380 900 1460 Line-up charts for Purdue's 'all freshman line-up (left) and an alternative second-unit (right)

Conclusion

Unless someone transfers or declares for the draft, Purdue's entire team could return. Which, if you're in the Big Ten, is a scary reality considering the room for development. A very real possibility is Ivey developing a jump shot, Newman becoming a more consistent playmaker while retaining his defensive prowess, Gillis getting a reliable three-point shot, and Edey putting on some muscle and playing more minutes. I'm personally hoping for more Ivey pick and roll with kick-outs to efficient shooters.

And in this report I have only scratched the surface of 2020-21's data. We could compare Thompson and Hunter Jr, find the best transition line-up; if I had play data, we could create the best groups to run certain actions; we could develop the best front-court combination, find the best baseline out-of-bounds group, see where different players need to develop by analysing their shooting charts, and so much more.

E: [email protected] 5 P: 380 900 1460