Sunday, August 1, 2021

U.S. Men (Indoor) Eliminated from 2020(21) Olympics

The U.S. men's indoor squad has missed the eight-team medal tournament, losing its final pool match to Argentina. Vinnie Lopes at Off the Block has a statistically laden summary (link).

Wednesday, July 21, 2021

Kentucky Wins 2020 (held in 2021) NCAA Women's Title; Hawai'i Takes 2021 Men's

It was an unusual spring for U.S. collegiate volleyball, thanks to COVID-19-related adjustments, with the women's championship (typically decided in December) and the men's championship (typically being decided five months later) being held only two weeks apart. The women's final was played on Saturday, April 24, 2021, with the men's on May 8. Having nearly three months to digest these matches, I present my analyses of the championships below.

WOMEN'S

For starters, here's a sentence I never expected to write in my lifetime (I'm 58): The Kentucky Wildcats are the new NCAA women's volleyball champions.* UK stopped Texas in four games, 20-25, 25-18, 25-23, 25-22, to claim what really is the 2020 championship (the 2021 title will be determined this coming November).

True, Kentucky was the No. 2 seed. However, previous high seeds from outside the power conferences (Big 10, Big 12, Pac 12) have rarely lived up to their placements**, so I remained skeptical. In the end, however, Kentucky proved to be a more reliable pick than even No. 1 seed Wisconsin, which entered the tournament undefeated, but bowed out in three to No. 4 Texas in the national semifinals.

Kentucky led the nation in team hitting percentage during the regular season (.361) and, to a large extent, rode that hitting to the national championship. Wisconsin came out better than Kentucky on my Conference-Adjusted Combined Offensive-Defensive (CACOD) measure, which is based on each team's own regular-season hitting percentage (HP) divided by the aggregate hitting percentage a team allowed its opponents (with this ratio multiplied by a strength-of-conference adjustment factor). Wisconsin hit .342 in the regular season (a bit below Kentucky's .361), but the Badgers allowed their opponents to hit a combined .128 (compared to .144 for the Wildcats' opponents). The Big 10's higher conference strength (1.25) than the SEC's (1.00) also made Wisconsin look better:

Wisconsin: .342 own HP/.128 opponents' HP = 2.67, which when multiplied by the Big 10's 1.25 conference adjustment factor = 3.34. 

Kentucky: .361 own HP/.144 opponents' HP = 2.51, which when multiplied by the SEC's 1.00 conference adjustment factor = 2.51.

At no time was Kentucky's kill-production more effective than when the Wildcats had the opportunity to close out the championship match against Texas in Game 4. Looking at a portion of the Game-4 play-by-play, once the Wildcats had overcome the Longhorns' early 6-1 edge to take a 15-13 lead, Kentucky successfully kept Texas at arm's length. A trailing team cannot afford merely to trade side-outs, but must put together scoring runs on its own serve to catch up. Yet, as shown in the following screenshots, five of Texas's seven final serving stints consisted of one serve only (the other two consisting of two serves). And, nearly always, it was Kentucky kills (highlighted in yellow) that kept Texas from gaining any ground. (You can click on all graphics to enlarge them.)


Another way to examine Kentucky's hitting attack is through usage/success graphs. In the two graphs shown below (the top one for the championship match vs. Texas and the bottom one for the Wildcats' four-game semifinal victory over Washington), each of Kentucky's five most active hitters (Madi Skinner, Avery Skinner, Elise Goetzinger, Azhani Tealer, and Alli Stumler) is depicted by a rectangle. The width of each rectangle represents the percentage of the team's hitting attempts taken by a player. For example, against Texas, Stumler took 34% (.34) of Kentucky's total number of swings (51/152), the most of any Wildcat, so her rectangle is widest. The height of each rectangle denotes the player's hitting percentage in the match, which was .471 for Stumler in the title match. Rectangles with the largest area convey great productivity by the hitter: a large number of kills on a large number of hitting attempts.


Looking at Kentucky's graphs against Texas and Washington one atop the other allows us to discern at a glance any changes in the Wildcats' allocation strategy between the two matches. For example, Kentucky set Stumler considerably more often (34% of the team's hitting attempts) in the final match than in the semifinal (23%). Changes in players' hitting percentages, such as Madi Skinner's improvement from .360 in the semifinal to .455 in the final, are also evident.

Before leaving the women's tournament, I wanted to revisit Wisconsin's concluding matches. Due to COVID, Big 10 teams played only conference matches during the regular season. The Badgers went 15-0 in this perennially strong conference, sweeping every match with the exception of three that went 3-1 (vs. Illinois, Michigan State, and Minnesota). However, both matches with Nebraska (ranked No. 5 nationally at the time), both matches with Penn State (No. 9 at the time), and one match with Minnesota (No. 5 at the time) were cancelled. It seems, in retrospect at least, that the missed opportunity to play these matches likely cost Wisconsin in terms of tournament sharpness.

The Badgers breezed through their first two NCAA tourney matches against Weber State and BYU, before hanging on 15-12 in the fifth game vs. No. 8-seed Florida in the round of eight.*** Now, Florida is an excellent team, in fact the only team all year to beat Kentucky (the Gators and Wildcats split their two SEC matches). Still, the decline in hitting percentage vs. Florida (relative to Big 10 play) among three leading Wisconsin hitters (6-foot-8 middle Dana Rettke, 6-2 middle/right Devyn Robinson, and 6-4 middle Danielle Hart) was considerable.
Interestingly, Robinson and Hart recovered nicely in their hitting vs. Texas, but it was not enough. As a team, the Longhorns outhit the Badgers, .301-.220.

MEN'S

Due to the COVID-related cancellation of the 2020 NCAA men's season, 2019 runner-up Hawai'i had to wait two years for another shot at the title. This time, the Rainbow Warriors made good on the opportunity, sweeping BYU, 25-21, 25-19, 25-16.

As this match wore on, Hawai'i looked more and more like it could attack the ball unchallenged. BYU recorded a healthy 5.5 blocks in Game 1 (really 5, as the extra half-block comes from awarding .5 credit to three blockers who went up together). However, the Cougars had zero blocks in Game 2 and two in Game 3 (7.5 total). Hawai'i hit .381 for the match (.400, .333, and .400, respectively, in Games 1, 2, and 3). Also, the Rainbow Warriors had only nine hitting errors on the night; we know seven of these are from BYU's "7.5" blocks, so that means UH spiked only two balls out of bounds. 

The Bows' Rado Parapunov, who started off hot in the 2019 final before cooling off, hit .357 this time vs. BYU on 13 kills (with three errors) on 28 swings (one-third of Hawai's overall 84 spike attempts). Several of Parapunov's teammates had even higher hitting percentages, albeit in far fewer attempts (Patrick Gasman, .545, 7-1-11; and Chaz Galloway and Guilherme Voss, each .667, 6-0-9).

Before I go, I wanted to mention that the Hawai'i athletic website's box score from this match is a very elaborate one, containing far more than the usual statistics. As shown in the following screenshot, the extended box score breaks down hitting attempts into first-ball attacks (immediately upon serve-receipt), transition attacks (once a rally has started), and first transition attacks. Hawai'i hit better on first-ball attacks (.524) than it did on transition attacks (.238).

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*Any more than I expected to write about a post-1908 World Series win by the Chicago Cubs or an NBA title by the Toronto Raptors (2019) or Milwaukee Bucks (2021).

**Examples include the 2019 Pitt squad that was seeded No. 6 and lost in the second round, and Kentucky itself, which as the No. 4 seed in 2017, lost in the Elite Eight to Nebraska.

***In the usual 64-team field, a team must win four matches to reach the Final Four. However, due to COVID, this spring's NCAA tourney consisted of only 48 teams.

Friday, April 16, 2021

2020 (held in 2021) NCAA Women's Tourney Reaches Round of 16

The NCAA women's tourney is now down to 16 teams, who will play on Sunday (except for Wisconsin vs. BYU on Saturday). Fourteen of the 16 national seeds have advanced this far. The two exceptions are Western Kentucky, which upset No. 15-seed Washington State in five games and will now face No. 2-seed Kentucky; and Pitt, which swept No. 14-seed Utah and will now take on No. 3-seed Minnesota.

In my tournament preview (previous posting below), I identified Western Kentucky as a leading upset candidate, based on the Hilltoppers' ratio of nearly 3 (2.91) between their own season-long offensive hitting percentage (.355) to the hitting percentage they defensively allowed their opponents (.122). (WKU's conference-difficulty adjustment in Conference USA was 1.00, so the Hilltoppers' ratio statistics is not changed by multiplying by 1.00.) 

 Another team on my radar was High Point, whose ratio was an even more gaudy 3.29 (=.296/.090). Multiplying by the Big South adjustment factor of .75 yields an adjusted ratio of 2.47 for the Panthers. High Point scored a first-round win over Central Florida, but was then swept by No. 7-seed Purdue in the second round.

I just checked Pitt's regular-season statistics for own and opponents' hitting percentages. They were  .262 and .146, respectively. Dividing .262/.146 = 1.79 and multiplying by 1.10 for the ACC conference adjustment, yields an adjusted ratio of 1.97.

Monday, April 5, 2021

Belated 2020 NCAA Women's Brackets Announced for COVID-Disrupted Season

Typically, the NCAA women's tournament is held every December. Against the backdrop of COVID-19, however, this has not been a typical season. Back in September 2020, the NCAA moved forward on a plan to shift several fall championships to spring, including women's volleyball. Some conferences (such as the Big 10 and Pac 12) opted to delay their entire women's volleyball seasons from fall 2020 to winter/spring 2021. Others (such as the Big 12) stuck to the usual framework and played the bulk of their schedule in fall 2020, but added some 2021 matches to stay sharp for the national tourney. The SEC played a little less than half of its conference schedule in the fall and a little more than half of it in the spring. Throughout this makeshift season, of course, numerous matches were postponed or cancelled.

The regular season has now been played and here we are, ready for the NCAA tournament. Only 48 teams (down from the usual 64) will participate and the tournament will take place entirely in Omaha, Nebraska. The brackets are available here

Wisconsin, last year's national runner-up, has remained true to form, going 15-0 in a conference-only season and sweeping all but three matches (which the Badgers won 3-1). Beyond the Badgers, however, the field features several oddities.

Stanford, winner of the last two national titles (and three of the last four), is absent. The Cardinal was able to play only 10 matches this season and went 2-8.

Kentucky is seeded No. 2, higher than I can recall the Wildcats ever being seeded (a little research shows UK was the No. 4 seed in 2017). UK went 19-1 in a conference-only schedule, its only loss coming to Florida (the No. 8 national seed, and with whom the Wildcats split two matches). Kentucky hit .361 as a team for the season, the highest in the land.

Perennial national contender (and seven-time champion) Penn State is seeded No. 13. Many of the other high seeds are familiar faces (No. 3 Minnesota, No. 4 Texas, No. 5 Nebraska, No. 6 Washington).

Readers of this blog will know that I developed a statistic in 2011, the Conference-Adjusted Combined Offensive-Defensive (CACOD), to gauge teams' prospects for doing well in the NCAA tournament based on their regular-season hitting percentages and opposition hitting percentages. It is explained here. For context, no team with a CACOD below 1.91 (which was recorded by 2016 champion Stanford) has won the NCAA women's tournament. CACOD values for the top four national seeds are as follows.

Team Hitting% Opp Hit% Ratio Conf Adj Final CACOD
Wisconsin .342 .128 2.67 x 1.25 3.34
Kentucky .361 .144 2.51 x 1.00 2.51
Minnesota .262 .191 1.37 x 1.25 1.71
Texas .333 .168 1.98 x 1.20 2.38

Wisconsin's CACOD of 3.34 is the highest ever recorded, surpassing the 3.09 recorded by Penn State in the 2014 regular season. That Nittany Lion squad went on to win the NCAA tournament. Hence, if all goes according to form, the victorious fans (however many of them are admitted for live attendance) will be singing "On Wisconsin."

If you're looking for possible upsets, some other teams with high CACOD values are:

  • Western Kentucky .355/.122, ratio = 2.91 (x 1.00 for Conference USA), CACOD = 2.91
  • High Point .296/.090, ratio = 3.29 (x .75 for Big South), CACOD = 2.47

Action gets underway a week from Wednesday, on April 14.

Tuesday, January 14, 2020

Stanford Sweeps Wisconsin for NCAA Women's Title, Aided by Multifaceted Blocking Game

With Stanford's win over Wisconsin for the NCAA national women's championship about a month ago coming so easily, 25-16, 25-17, 25-20, it was hard at first to come up with a statistical angle. The Cardinal, led by 6-foot-6 senior outside-hitter Kathryn Plummer's torrid spiking (.459 on 22 kills and 5 errors on 37 attempts), outhit the Badgers, .358-.152 (box score). Madeleine Gates, a Stanford graduate transfer who finished her degree at UCLA, also came up big (.529, 10-1-17). I've already written a lot on Plummer's hitting, however, so I wanted to focus on something else. Then, an idea from five years ago popped into my mind.

As I wrote in February 2015 then-Penn State men's assistant coach Jay Hosack (now head men's coach at George Mason) noted on the Internet-radio show The Net Live that, "blocking should be evaluated more broadly than via direct stuff-blocks for points." For example, blockers could slow the ball down from a spike attempt, making it easier for the players behind the blockers to dig the ball. Guests on that episode of The Net Live referred to slowing the ball as "control blocking." I prefer the term "dampening" the spike attempt.* Here is a schematic I created to illustrate dampening:


Blockers can also ricochet the ball back to the attacking team's side of the net, with the original attacking team keeping the ball in play. A "block back in play" probably would not be as advantageous to the blocking team as would a dampening, as the original attacking team can set up again for a spike. However, a block back in play would buy the blocking team some time to set up to receive the next spike attempt.

I had never gotten around to examining Hosack's idea, as one could not do so simply from box scores and would have to engage in careful observation and charting while watching matches. Perhaps some teams and volleyball statistical services compile dampenings and block-backs, but I'm not aware of how to access these numbers. I had forgotten about Hosack's idea until, for whatever reason, it re-emerged in my mind after the Stanford-Wisconsin match. I decided now was the time to follow through on it using video of the match on YouTube.

With pencil in hand, I began recording Stanford and Wisconsin's dampenings and block-backs, as shown in the following graph. I also plotted stuff blocks (listed in the box score simply as "blocks). As can be seen, Stanford outperformed Wisconsin in all three areas -- stuff blocks, dampenings, and block-backs -- on the night.


If one has the time and interest in charting dampenings and block-backs, I would recommend doing so. The three measures together yield a richer measure of blocking success beyond just stuff blocks. Conceivably, a team could compile very few stuff blocks, but a large number of dampenings, for example. Looking at the box score alone, one would not appreciate the team's blocking success.

***

Every year since 2011, I have computed my Conference-Adjusted Combined Offensive-Defensive (CACOD) measure to predict success in the NCAA women's tourney. I noted before this year's tournament that the lowest CACOD score for a team that went on to win the national title was 1.91 (Stanford, 2016). Stanford's was 2.05 this season, whereas Wisconsin's was 1.85. Hence, had the Badgers defeated the Cardinal, Wisconsin would have been become the team with the lowest CACOD to win the championship.

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*According to a scenario from the NCAA manual, a defender fielding a ball after a dampening block still receives a dig in the statistics, even though the ball has been slowed down:

Team White player No. 1 attacks the ball. The ball goes off Team Blue player No. 1 and ... (b) goes to Team Blue player No. 2 who keeps the ball in play. RULING: ... In (b), Team Blue player No. 1 is not awarded a block but Team Blue player No. 2 is awarded a dig.

Thursday, December 19, 2019

Preview of NCAA Women's Final Four (2019)

This year's NCAA women's Final Four, which begins shortly, features the Bears of Baylor, two of the B1G's three burrowing animals -- the Wisconsin Badgers and Minnesota Gophers* -- and a color, the Stanford Cardinal.

By most accounts, Minnesota would probably be the team considered least likely to win the national title. Anecdotally, in watching some Gopher matches this season, my sense was that blocking was the team's strength.

I therefore decided to compare the Final Four teams on their blocks per opportunity. The number of opportunities a team has to score points via a stuff block is the number of hit attempts by opponents, removing the number of spikes hit out of bounds or into the net. Such attempts gone awry can be calculated by taking opponents' aggregate hitting errors and subtracting those errors due to your own aggregate blocks.

These calculations revealed all of the Final Four teams to be extremely similar in the proportion of blockable (i.e., not out of bounds) balls they actually blocked. These proportions showed that each team blocked 8% of their aggregate opponents' spike attempts they could have blocked (ranging from .080-.087).

Where the teams differed more dramatically is in the number of opposition spike attempts they allowed: Minnesota 4453, Wisconsin 3834, Baylor 3428, and Stanford 4070. At first glance, at least, even when Baylor and Wisconsin (relative to Minnesota and Stanford) don't score kills, they appear to pressure their opponents enough to take them out of system and prevent them from mounting attacks.

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*The other being the Michigan Wolverines.

Saturday, December 14, 2019

Brief Observations on NCAA Women's Elite Eight Day

Baylor and Washington are tied at one game apiece (Baylor 25-20, U-Dub 25-21). Baylor has hit well in Games 1 (.538, 16 kills, only 2 errors, on 26 attempts) and 2 (.355, 15-4-31).  Washington had only three hitting errors in Game 2 (.367, 14-3-30). The Huskies' Samantha Drechsel is hitting .625 after two games (12-2-16)... Bears take Game 3, 25-19, on continued torrid hitting (.615, 17- 1-26 in Game 3)... Baylor closes out match 25-18 to take program's first trip to Final Four. Bears hit .444 in Game 4 (16-4-27), .479 for match (67-11-117)...

Wisconsin records a 3-0 sweep of Nebraska (25-18, 25-22, 25-19) for the third time this season to advance... No suspense in the last two matches of the day, either -- not even any deuce games -- as Minnesota sweeps Louisville (25-21, 25-14, 25-16) and Stanford does the same to Penn State (25-22, 25-15, 25-17). Stanford's Kathryn Plummer records another high hitting percentage on a high volume of attempts (.512, 24-2-43).

U.S. Men (Indoor) Eliminated from 2020(21) Olympics

The U.S. men's indoor squad has missed the eight-team medal tournament, losing its final pool match to Argentina. Vinnie Lopes at Off th...