Scout VB

coaching volleyball

2018 NCAA Championship Breakdown

Match AnalysisJoseph Trinsey3 Comments

In the 2018 NCAA Women’s Volleyball Championship, Stanford edged out Nebraska in a close 5-set match. We saw in this post that Nebraska won their semifinal match over Illinois despite being outscored by 1 point. The margin in the final was the same, but this time Nebraska wasn’t able to pull it out.

End of match screen. GMS Stats app.

End of match screen. GMS Stats app.

The first two sets were close, but sets 3 and 4 saw each team trading blowouts. In an eerie recall of the semifinal vs Illinois, a challenge decided a crucial point late in the 5th set, but this time it didn’t go Nebraska’s way. Stanford won the 5th and earned their 8th National Championship.

In a match this close, we expect the margins to be thin statistically, and that was the case in this match.

Stanford Point Differential Screen

Stanford Point Differential Screen

Both teams were at about 59% sideout for the match, which, while lower than their season averages, is also higher than either team typically allowed. This is common- seeing the overall sideout rate in a match between two top teams end up about halfway between what those teams sided out and what they allowed against most other opponents. Let’s break down the statistics more to see if they can tell us where the slim margins of victory came from. All screens and statistics courtesy of the GMS Stats App!

When I analyze a match, the first thing I do is look at the overall Point Differential, and see the Sideout level for the match as a whole. The next thing I like to do is look at the 3 Key Factors to Sideout. We’ll look at both the Stanford and Nebraska Sideout Key Factors to see the similarities and differences.

Stanford Sideout Key Factors

Stanford Sideout Key Factors

Nebraska Sideout Key Factors

Nebraska Sideout Key Factors

Plenty of similarities here. Both teams passed well. Nebraska hit significantly better In-System (attacking after a Good Pass) than Stanford, but Stanford was better Attacking Out-of-System- after a Bad/Medium Pass or in transition. So Nebraska was In-System a lot, and hit well when they were. That’s usually a recipe for success. Let’s look at the defensive side of the ball to find out a little more information.

Stanford Opponent Sideout Screen

Stanford Opponent Sideout Screen

Nebraska Opponent Sideout Screen

Nebraska Opponent Sideout Screen

Again, plenty of similarities. Nebraska dug a bit better while Stanford blocked better. Blocking can be a deceiving stat because while Stanford only outblocked Nebraska 10 to 9, they did so while only giving up 22 tools/block errors, while Nebraska gave up 34. Hitters on both teams scored off the block well, but Stanford was better here. However, this was compensated by Nebraska being the better defensive team. Again, percentages come in handy. Both teams had 69 digs, but Nebraska dug those 69 balls on 100 chances, while Stanford had 119 chances to dig.

Since Nebraska hit better on the match, we see, as we often do, that backcourt defense has a bit stronger of an effect (in NCAA Women’s volleyball) than blocking on the opponent hitting efficiency.

Finally, we see the serving. Both teams knocked the opponents Out-of-System at a similar rate. All told, the Key Factor statistics were close, as you might expect when the Sideout % (and thus, overall points scored) is so close.

So what was the difference?

If we walk it back to the first image in this post, we see there were 209 total points scored this match: 105 by Stanford and 104 by Nebraska. Since Nebraska out-hit Stanford, we’d expect them to be better within the rally, and that was true. If we take away service errors and aces, and isolate only the points where a rally took place (meaning at least one of the teams got a chance to attack), we see the following:

Total Rally Points: 182

Nebraska: 94 (72 Kills, 9 Blocks, 13 Stanford Errors)

Stanford: 88 (65 Kills, 10 Blocks, 13 Nebraska Errors)

So indeed, Nebraska was 6 points better within the rally. But now let’s look back at the No-Rally Points, where there was either an ace or a missed serve:

Total No-Rally Points: 27

Nebraska No-Rally Points: 10 (2 Aces, 8 Stanford Missed Serves)

Stanford No-Rally Points: 17 (9 Aces, 8 Nebraska Missed Serves)

So Nebraska was 6 points better within the rally, but Stanford was 7 points better when no rally happened at all! We find that this happens quite a bit- the team that wins the match was no better, or even slightly worse when, “volleyball happened,” but a substantial margin in the serve-pass game can often compensate for that.

With so much attention on Stanford’s size and power at the net, and the flashy digs by libero Morgan Hentz, it’s easy to forget that the serve-pass game so often dictates the winner and loser, even (especially?) at the highest levels.

What Is Point Differential And Why Does It Matter? - Part 1

Stats LessonsJoseph TrinseyComment

In a previous blog post we showed the Point Differential screen of the GMS Stats App.

Nebraska Point Differential Screen; 2018 National Semifinal vs Illinois

Nebraska Point Differential Screen; 2018 National Semifinal vs Illinois

But what is Point Differential? Why does it matter? How does it affect me as a coach?

Point Differential is simply the difference between how many points I score, and how many points my opponent scores. It’s a fancy way of saying, “the score.” Most of us intuitively grasp the following two equations:

Scoring More Points Than The Other Team = “Good”

Scoring Fewer Points Than The Other Team = “Bad”

“Great, Joe, score more points than the other team. I can see why the National Team hired you.”

Calm down, unnecessarily sarcastic imaginary reader.

This screen from the app actually shows Sideout Differential, which gives us a little bit more information. This screen shows Nebraska (“your”) Sideout and Illinois (“Opponent”) Sideout. What’s the difference between Sideout Differential and Point Differential? It’s really just a matter of perspective.

Quick Volleyball Stats 101 Lesson:

A “Sideout” is any time the other team starts the rally with a serve and we win the point, whether they miss the serve, or we win on the first chance to attack, or it’s a long rally that we win in the end. If the rally started with the opponent serving, and we win the point, that’s a Sideout. (So an Opponent Sideout is any time we start the rally with the serve and the opponent wins the point.)

“Sideout %” is the number of chances we had to sideout (also: the number of times the opponent serves) divided by the number of times we actually sideout. So if the other team serves 100 times, and we sideout 54 times, our Sideout % is 54%.

So Sideout Differential is just a way of looking at Point Differential from a different perspective. You cannot have a better Sideout % than your opponent, but a worse Point Differential. And you cannot have a better Point Differential than your opponent, but a worse Sideout %. So why use Sideout Differential instead of Point Differential?

The best reason is that Sideout % is a reliable indicator of level of play. In U12 volleyball, the serving team has an overwhelming advantage. Sideout % is well under 50%. At the professional level, the receiving team now has the advantage. Both teams will Sideout well above 50% in most matches. So imagine two different matches:

Match 1: Sideout 41%, Opponent Sideout 40%

Match 2: Sideout 61%, Opponent Sideout 60%

In both these matches, the Differential was 1%, but the style was different. Match 1 was a defensive battle where both teams were going on runs. Match 2 was more of a sideout battle, with the offenses at an advantage over the defenses. Knowing the differential as well as the overall sideout rate between the two teams allows you to get an idea of the overall level of play, as well as how your team fared.

In Part 2, we look at more uses of Point or Sideout Differential and go from looking at one match to multiple matches.