Soccer, Hoops Next to Seed Using MPR
August 6, 2019
By Rob Kaminski
MHSAA benchmarks editor
As the topic of seeding for MHSAA Tournaments continues to swirl in the air of numerous committee meetings on an annual basis, one of the primary concerns continues to focus on the simple question: “How?”
The MHSAA for years has been working behind the scenes on potential formulas which could best be used as a standardized tool to assist in measuring strengths of teams in a given sport.
This spring, the MHSAA introduced the Michigan Power Rating in the sport of Boys Lacrosse. The Representative Council approved limited seeding beginning in 2019-20 for girls and boys soccer and girls and boys basketball, and MPR will be the metric to determine which two teams must be seeded on opposite sides of District brackets in those sports.
“The boys lacrosse tournament has been seeded since it was added as an MHSAA-sponsored sport in 2005. The seeding is done by committee based on several criteria, one of which was statewide power rankings generated by a third-party website. In the Fall of 2018, that website ceased operation – it was the perfect opportunity for the MHSAA to develop its own data-driven, purely objective ratings system and incorporate that data into the seeding criteria,” said Cole Malatinsky, administrative assistant for the sport.
“The benefits of the new MPR system have been already mentioned – it is MHSAA controlled, simple, objective, and transparent, and it can be used by other MHSAA sports in the future.”
MPR is a computer rating formula similar to the popular RPI rating. MPR provides a way to measure a team’s strength relative to other teams, based on games played against other MHSAA tournament teams, largely on the strength of their opponents’ schedules. MPR is purely objective using only the game results listed on MHSAA.com – there is no subjective human element.
What is the basic MPR formula?
MPR is calculated using wins, losses and ties for games played between teams entered into the MHSAA tournament. The final MPR number is 25% of the team's winning percentage, plus 50% of its opponent's winning percentage, plus 25% of its opponent's opponent's winning percentage.
MPR = (.25 x W%) + (.50 x OW%) + (.25 x OOW%)
The MPR formula can be applied easily to other MHSAA team sports.
What game data is included in the formula? What game data is not?
MPR looks only at results between opponents entered into the MHSAA postseason tournament. Wins, losses and ties in multi-team shortened game tournaments (lacrosse, soccer) also count. Forfeits also are counted as wins and losses.
MPR does not use the specific scores of a game or the margin of victory in a game. The location of a game is not included in the MPR formula, and the formula weighs results at the beginning of the season the same as results at the end of the season. Scrimmages are not included.
Why use the MPR formula?
Different rating systems have been used in the past or have been recommended to the MHSAA. We wanted to have a rating system where the data was controlled and stored in house and could be used for any sport featuring head-to-head competitions.
With its own rating system the MHSAA also can control the different components of the formula, thus keeping the tenets of scholastic competition at the forefront (like not including margin of victory in the formula). Finally, by listing all scores and team schedules online, as well as showing the MPR calculator on each team schedule page, the ratings are transparent and can be replicated easily.
CALCULATING MPR
What are the detailed components of the MPR formula?
You need three numbers to calculate your MPR: winning percentage (W%), opponent’s winning percentage (OW%) and opponent’s opponent’s winning percentage (OOW%).
How do you calculate winning percentage (W%)?
Divide the number of wins by the number of total games played. A tie is worth half a win. For MPR purposes, find the winning percentage against all teams that will play in the MHSAA tournament (MPR W%). Games played against out-of-state teams, varsity “B” teams, junior varsity teams, non-school club teams, and any other non-MHSAA tournament participants should not be included when calculating winning percentage. W% should be an easy number to calculate.
How do you calculate opponent’s winning percentage (OW%)?
Average the winning percentages of a team's opponents. When calculating the winning percentage of a specific opponent, use the opponents "Adjusted Winning Percentage" (ADJ W%). Adjusted winning percentage eliminates all games the team played against that opponent (as well as its games against non-MHSAA opponents).
For instance, if the team beat an opponent with an overall record of 4-1, use a record of 4-0 (1.000) for that opponent. If the team lost to an opponent, use a record of 3-1 (.750). Find the ADJ W% for all opponents, and then take the average. If a team plays an opponent team twice, that opponent’s ADJ W% will be counted twice.
OW% is not calculated via the combined record of the opponents; instead take the average of all opponent’s winning percentages.
How do you calculate opponent’s opponent’s winning percentage (OOW%)?
Use the same process described above, except calculated for the opponents of a team's opponents. This number is much harder to manually calculate, so the OW% for every team is listed on the MPR page of the MHSAA website.
Again, simply take the average of all opponent’s OW%.
How often is MPR calculated?
MPR is calculated about every five minutes. Enter a score and a minutes later the team MPR and the MPR of all the team's opponents will update.
How much will my MPR change throughout the season?
You will see wild MPR swings in the beginning of the season, but after about 10 games played your MPR will start to level out. At 20 games played you will see very little movement with each additional game played.
My score is missing. How can it be added?
This is a crowd-sourced system. Any registered user of MHSAA.com can add a missing score. ADs, coaches, parents, students and fans all can login and enter a score for any game.
What are some common errors when calculating MPR?
When calculating your team’s winning percentage, only include games against MHSAA-tournament teams. When calculating your opponent’s winning percentage, don’t include the games they played against you. When calculating ties, count the game as a half-win and half-loss.
What happens if a game is cancelled?
Because the MPR system works off of averages, it will not make a difference in the final MPR if a game cannot be rescheduled. It would not penalize, nor benefit, any team involved in that scenario.
USING THE WEBSITE
Where can I find game scores?
A list of statewide scores for all sports can be found in the MHSAA Score Center. To find a schedule for any team click on “Schools & Schedules” in the top navigation bar, search for the school, then once on the school page click the sport. You can also see a list of all schools (with links to schedules), on the statewide MPR list.
“We continue to have great success in score reporting for varsity boys lacrosse contests. While we state that schedule submission and score reporting to MHSAA.com are required, athletic directors and coaches understand that in order for MPR data to be accurate, we need consistent and accurate score reporting,” said Malatinsky. “MHSAA.com is now the primary site for high school boys lacrosse schedules, results and ratings in the state.”
How should I use the statewide list of teams and MPR?
Linked to the boys soccer page (and eventually to be added for both basketball pages and girls soccer) is a statewide listing of all Michigan Power Ratings (MPR) for teams entered into the MHSAA postseason tournament for that sport. Linked on the MPR page is an explanation of the District draw formula, describing when and how teams will be placed on the bracket.
The MPR data updates every five minutes. Click on the column headings to sort the data. You also can use the drop-down menu to show teams in one Division, or type a District number in the box to filter teams for that District (Region for boys lacrosse).
You also can click on any school name to go to its schedule page.
How do I read the school schedule page?
The schedule at the top of the page shows the date and opponent for all scheduled games, and results for games already played. If results are missing, click “Submit Score” to add a game score.
Below the game schedule is the MPR Calculator. The calculator is split into three sections. The first section shows the three MPR component scores for the team, as well as the team’s current MPR score. The second section shows the MPR information for the team’s opponents – specifically, for the opponents the team already has played (actually, for games where scores have been submitted). Only these games are included in the MPR calculation.
The third section highlights future opponents. The MPR data for future opponents are not used in the MPR calculation for the team.
PHOTO: East Kentwood and Ann Arbor Skyline play for last season’s Division 1 boys soccer championship.
Zeinstra Finishing 4-Year Byron Center Run Among School's All-Time Greats
By
Dean Holzwarth
Special for MHSAA.com
February 15, 2024
BYRON CENTER – As an incoming freshman four years ago, Lily Zeinstra was immediately thrust into a starting role on the Byron Center varsity girls basketball team.
While it was an overwhelming experience, Zeinstra embraced the opportunity, and believes the early demands placed on her helped pave the way for what has become an outstanding high school career – and spot among the best in school history.
“My freshman year was scary,” she said. “Just coming in and starting on varsity. And in our first game, I had to guard Jillian Brown from East Grand Rapids, who was a really good player. I feel I was pushed into a big role on our team at a really early age, but I think that has helped me over the last four years to develop into the player I am today.”
Now a senior standout, the 5-foot-11 Zeinstra has been a mainstay in the Bulldogs’ starting line-up throughout while helping lead the program to four years of success.
She recently became the school’s all-time leading scorer, surpassing 1,500 points for her career.
“I have to give credit to my teammates,” Zeinstra said. “Through the years I've been in different scoring positions, but I've always been on a team that has trusted me with the ball in tight game scenarios.
“I’ve been told by my coaches since I was younger that I'm a scorer and they need me to score, and that's been my role so I feel like scoring all those points is what I needed to do to help our team win. That’s the most important part.”
Zeinstra, who committed to Division I Butler University last spring, has been the focal point every season and has enjoyed her role as a team leader. Byron Center (14-4) is a combined 68-14 over her four seasons.
“I’ve definitely learned a lot about being a leader and having different roles that I can have on teams,” she said. “Coming in freshman year, my job was to work hard and I was one of the top defenders, so I was guarding the other teams’ best players.
“As years went on, our team lacked numbers so I became more of a scorer, especially last year. I worked on posting up down low and scoring all around the basket, and this year even more trying to further my game and score better. I'm playing college basketball next year, and that’s what they need me to do.”
Zeinstra also had the opportunity to play two years at Byron Center with her older sister, Avery, who plays now at Grand Valley State.
“I feel like I didn’t enjoy it enough when I was in it with her,” Zeinstra said. “But I loved her class so much. There were two other seniors who she played with all four years, and they were big leaders and taught me about the culture here at Byron Center. I really enjoyed playing with them.”
Zeinstra is averaging 25 points per game this season and had a career-high 39 points against Grandville in late December.
First-year Byron Center coach Cam Burns, who replaced longtime program leader Jen Slot, knew all about Zeinstra before being hired.
“I saw her on the AAU circuit and I watched her play for a couple years, and I have friends who spoke highly of her,” Burns said. “When I got the job I wanted to check her out, and I saw her pace and how she plays the game was very special.”
Burns said Zeinstra possesses unwavering confidence and the ability to score several ways.
That mentality has come from countless hours in the gym and a strong work ethic.
“She’s one of the hardest working kids in practice, and she just wants it,” he said. “And she’s a sponge, always looking at different skills and movements to try and get a better look at the rim.
“And it’s about the time and effort she puts into the little details. She makes plays, and I’m not surprised when I see something from her on the court when others are taken back by it. She continues to show why she is so good.”
The adjustment period for Zeinstra was difficult at the onset of this season.
She was getting accustomed to a new coach, as well as a new group of varsity players after the loss of several seniors.
“It was hard at the beginning because I had been running Coach Slot’s plays and offense for three years, and I knew what to expect going into every game and every practice,” Zeinstra said. “When Coach Burns came in, he brought a different vibe and a different culture, and it was the first year I had to get used to playing with new players and a new coach. I was learning things all over again.”
Zeinstra has adapted well to her new surroundings.
“It’s been going pretty good, and we had a couple big wins last week and we are in first place in our conference,” she said. “We should be able to pull another conference championship out – fingers crossed.”
The Bulldogs are chasing their fourth straight conference championship and have a one-game lead entering Friday’s Ottawa-Kent Conference White game against Grand Rapids Forest Hills Central. Their only conference loss was against Forest Hills Northern.
“It would be such a great accomplishment to win another one,” Zeinstra said. “We have had this winning culture in our program for so long, and with getting a new coach I was worried we were going to lose some of that. But I really feel like this team is buying into everything that Coach is saying and we are finally putting the pieces together and starting to win some big games.”
After a rocky start, Byron Center has adjusted well to its new coach and made giant strides. The Bulldogs dropped their first two games of the season to East Kentwood and reigning Division 1 champion Rockford, but since have won 13 of their last 15 games.
“We started out 0-2 against two of the top teams in the state, and it was just learning a new system and a new process and feeling each other out,” Burns said. “As weeks have gone by, they are starting to trust in each other and trust me. They’ve started to trust in the process.
“After that first win we got to celebrate that, and it was special. From then on we started rolling, and we’re getting better day by day, continuing to trust in one another.”
The Bulldogs also will seek a third consecutive District crown when the postseason begins in a few weeks. Zeinstra is looking forward to a potential rematch with East Kentwood.
“I want another stab at them, and we like challenges,” Zeinstra said. “We feed off that, so I feel like we have a shot to win (Districts) again.”
Dean Holzwarth has covered primarily high school sports for Grand Rapids-based WOOD-TV for five years after serving at the Grand Rapids Press and MLive for 16 years along with shorter stints at the Ionia Sentinel and WZZM. Contact him at [email protected] with story ideas for Allegan, Kent and Ottawa counties.
PHOTOS (Top) Byron Center’s Lily Zienstra considers her options during a game against Rockford. (Middle) Zienstra, left, puts up a shot against Muskegon. (Photos courtesy of the Byron Center girls basketball program.)