Positive vs Negative Feedback or Regression to the Mean

I saw this video the other day. It is in name about whether punishment or reward is more effective. There are examples of anecdotal experiences with one or the other being more effective. I really like science, and this YouTube channel has a nice accessible approach to presenting science. It's also interesting to me as a coach for a couple reasons.

The obvious being that we have all been on teams or have had coaches where punishment was used as a primary method of improving performance. Maybe we are that coach. That coach has their own anecdotal evidence for that method of coaching. Hopefully we have also been in the opposite situation where reward has been used to encourage improved performance. This coach probably has some anecdotal experience, but they also happen to have empirical evidence backing them. In short, we all have anecdotal evidence backing our approach, but some approaches also have empirical evidence. The ones that are empirically backed are better, no matter what our anecdotal evidence says.

I also find it interesting because of the idea of regression to the mean as an explanation for some of that anecdotal evidence. I think we can use this information as coaches. Thinking about volleyball in statistical terms, every player has an average performance level for each skill of the game. The same could be said for team performance. There is going to be some variance in performance, and there is going to be a distribution of performance in each of the skills. Most of the time the attempts to perform the skill are going to be within a certain range. As the player improves, the average changes in a favorable direction, and the standard deviation is going to shrink, meaning less variance. Running this through the idea of the regression to the mean, when a player has an above average skill performance, the next performance will likely be closer to the average performance. It isn't always going to be this way, but over time more often than not, the subsequent attempts will be closer to the average. This is going to happen independent of other factors. If the player has improved significantly, the great performance will not have as big of a regression to the mean as in the past. One of our key objectives in helping players develop is in improving the mean. A great single instance of skill performance by itself is not an indication of improvement. One bad set is not a sign of danger, but multiple bad matches might be. When looking at performance, don't just evaluate the last match. Evaluate the last few.

Similarly, when looking at team performance, it's probably best to have the big epic set win come at the end of the match. I know, this is not something we can just choose to do. Looking back to NCAA men's national championships, there were two consecutive years where the same team won long sets. The first instance has BYU winning the first set 44-42. Even with sets going to 30 points that is a marathon set. They went on to lose the next two sets and eventually the match. Here we have a huge effort to win a set. Regression to the mean suggests there is going to be a let down just because of statistical probability. They played above average and then they played closer to average. Other team motivation, emotional let down, and every other reason sports commentators might mention may or may not be a factor, and they probably weren't a factor. It's just the tendency to get your team average with repeated attempts. The following year BYU won the 5th set 19-17, right after winning the 4th set 32-30. You could even look at Long Beach State's 30-15 1st set win as an above average performance where they will regress to the mean with a simultaneous regression to the mean for BYU's below average 1st set performance. Again, this is likely just a statistical phenomenon. It says nothing about team motivation or player character and toughness.

How can we use this as coaches? Our first concern is to help our players and team develop and structure practices to improve the average performance. Find out what statistical measures are most important indicators of success and measure performance in those stats. We want our players to improve and bring up those averages. I think this is where the competitive cauldron is a valuable tool. Second, when we are in a match we need to keep in mind that there is probably going to be a regression to the mean in performance, both good and bad. This is when coach as a psychologist or therapist comes into play. Someone does something incredible, and they will probably not be able to keep it up. Likewise, when someone commits an error, they will probably do better in subsequent attempts. We need to be our players' biggest cheerleader. Help them keep an even keel and not get too down when they regress to the mean. Help them to weather the storm.

The video mentions Thinking, Fast and Slowby Daniel Kahneman. It's a book about our two systems for thinking that are fast and slow. I'm partway through right now, and I just got to the part about regression to the mean (which mentions the Israeli fighter pilots the video talks about). There is a lot of good information for coaches to consider that should influence how we teach skills and coach players. There is also a lot of good information about cognitive biases and heuristics that will serve useful in evaluating what we look at in our efforts to improve our methods and how we are as coaches.

Thinking About Team Goals During Competition

I've written recently about a kills per set goal that might put a team in a good position to win the set. It has been on my mind a little since I wrote that, and it came up in my mind again while watching a college football game this weekend.

During the broadcast there was a graphic on screen with some stats for one of the teams. It showed the teams "Pillars" and showed the win-loss record when the team succeeded in that goal or standard. I couldn't find any mention elsewhere on the internet about those actually being team goals. It was a graphic with a sponsorship logo in the corner, so I can only imagine either the sponsor or the network compiled some stats and posted them for profit. I am aware of a time or two where broadcasters say something authoritatively, but speaking with the coaching staff says something different. I don't know that the coaching staff does have these standards, but the stats themselves were very interesting and best closer examination.

The first "Pillar" was to score 24+ points per game. That's pretty straightforward. The goal of most sports is to score more than the other guy. I don't know what the average football team scores, but 24 seems like a fair enough number. That adds up to the touchdowns and a field goal. Score more than that and you're doing pretty good. The team had a record of 81-12 when scoring 24+. That's a healthy 87%.

The second was to hold the other guys to 24 or fewer points. Taken together with number 1 it's obvious. 78-11 for 88% when the defense meets its standard.

Third is to score first. This one is less obvious to me, and much less applicable to a sort like volleyball where every play should end with a point. In a low scoring defensive battle in football, the first team to score might just be the only team to score. The team managed a 67-9 record for an 88% win percentage. That made me curious about how true this is with all football teams. I found this, suppressing primarily about professional football, where the writer factored in team quality. When the teams are considered equal, the team that scores first (touchdown) wins 2/3 of the time. That's a pretty big deal.

Next is to score every quarter. With the first goal in mind, this is a simple way to break that bigger goal into smaller, more manageable chunks. It also could be about consistent effort through the whole game. This one only gave the team a 43-8 record. At 84% this is the lowest of the five "Pillars", but that is still a favorable outcome.

Last is for the defense to score points. That's only going to happen with an interception run back for a touchdown, a fumble recovery run back for a touchdown, or a safety. These are all big plays, and are rare. The numbers bear this out. At 17-2 this is by far the smallest number of games, but the 89% is the highest winning percentage.

Putting these into volleyball terms and numbers might be interesting. It could be a simple goal sheet that players could use as mile posts on their way to a set win. The first two could easily be rewritten as the 13 kills per set and holding the opponent to 10 kills per set I've previously mentioned (link above). I'm pretty happy with those two as a starting point.

I'm not sure what to do with the other standards. I'm not satisfied that other stats correlate strongly enough to winning to use them as a basis by themselves. It might be good to use streaks of consecutive points. Instead of being the first to score, be the first to score 3 consecutive points. I don't have any kind of data on scoring steaks on competition, so I don't know how this will serve as a standard. Limiting opponent's streaks might be another place to go. Again, I don't have any kind of data to guide here.

I'm going to have to think about this more. I might have to add scoring steaks to the data I will collect in the future. What are your thoughts?

Perfection in Sports

Remember the Titans was on the other night. I love the movie and think it is kind of required viewing for cultural literacy, but I also like it for the depiction of sports and coaching. I like setting high expectations for my teams. I know those expectations will not always be met, but it is wonderful to watch what can happen when the team buys in to those expectations, works hard, and believes in themselves.

There is an exchange during the movie that really resonated with me. To the coach in me this is one of the most beautiful moments in the movie. But first some context:

Coach Boone: We will be perfect in every aspect of the game. You drop a pass, you run a mile. You miss a blocking assignment, you run a mile. You fumble the football, and I will break my foot off in your John Brown hind parts and then you will run a mile. Perfection. Let's go to work.

That is a high expectation. I think there is room to criticize the delivery and consequences, but that is a high expectation. This is the practice environment and the team culture that Coach Boone established. The team responded and had a very strong season.

Coach Boone: It's all right. We're in a fight. You boys are doing all that you can do. Anybody can see that. Win or lose... We gonna walk out of this stadium tonight with our heads held high. Do your best. That's all anybody can ask for.

Big Ju: No, it ain't Coach. With all due respect, uh, you demanded more of us. You demanded perfection. Now, I ain't saying that I'm perfect, 'cause I'm not. And I ain't gonna never be. None of us are. But we have won every single game we have played till now. So this team is perfect. We stepped out on that field that way tonight. And, uh, if it's all the same to you, Coach Boone, that's how we want to leave it.

Coach Boone paraphrases John Wooden really well here. They are in the middle of a tough game, and things aren't looking good for the good guys. Coach Boone is at that place where the expectations are there, but the only thing the team can do is give their best effort. Expectations and reality are at odds. Then one of his players steps up and shows real leadership and character. He's going to dig deep and do more. They all are. And every once in a while those expectations are met. Perfection.

Book Review - Coaching Volleyball Champions

I just finished reading Coaching Volleyball Championsby Mary Dyck and Ard Biesheuvel, a couple of volleyball coaches in Canada. It contains 11 chapters, each focusing on a successful volleyball coach from the US and Canada. The format for each chapter is a biographical introduction to the focal coach, the coach's answers to the same series of questions, and then 5 drills that the coach uses.

I'm much more familiar with the American coaches than the Canadian ones, but there are some great ones representing the USA: Marv Dunphy of Pepperdine, Carl McGown retired from BYU, Al Scates retired from UCLA, and Jim McLaughlin of Notre Dame (Washington at the time of publication). Dunphy and McGown are my coaching heroes, and McLaughlin and Scates have significant coaching credentials.

Each coach is asked questions like "What is a champion?" and "What are the most important ingredients of a championship team?" They are asked about psychology, motivation, goal setting, how their coaching has evolved, and thoughts on the different positions. There is a part of me that wishes the answers to each question from each coach were all in the same place, but having each chapter focus only on one coach gives a better sense of who he or she is. You can get a feel for who they are and what they do. You can see how the coach's philosophy informs the drills they use.

The selection of drills is not exhaustive, but it is a nice collection of drills used by some of the top teams in American and Canadian volleyball. There are 55 total drills and there is a handy drill finder in the back listing which drills address various desired training outcomes or topics.

Coaching Volleyball Champions is a very nice volleyball coaching resource. It can help with the practical side of coaching with the drills, and the more theoretical or abstract part of coaching with the question/answer portion. I highly recommend this for your coaching bookshelf and education.