Winning Research Articles

Win Ratio approach for the composite outcome of postoperative pulmonary complications: Secondary analysis of a harmonised and pooled database of three randomised clinical trials.

The win ratio analysis method might provide new insight on the impact of positive end-expiratory pressure (PEEP) on clinical outcomes. The aim is to re-analyse the results of the 'Re-evaluation of the effects of high PEEP with recruitment manoeuvres vs. low PEEP without recruitment manoeuvres during general anaesthesia for surgery' (REPEAT) study using the win ratio analysis. Individual patient data meta-analysis. Three international multicentre randomised trials. Patients undergoing general anaesthesia for surgery. High vs. low PEEP. Hierarchical composite endpoint of: all-cause hospital mortality; hospital length of stay; need for postoperative mechanical ventilation; severe pulmonary complications; and mild pulmonary complications. A total of 3774 patients undergoing general anaesthesia for surgery were included in this analysis. The median (interquartile range [IQR]) age was 57 [45 to 68] years and 2077 (55%) were women. A total of 3 560 720 comparison pairs were produced. The high PEEP group had a higher percentage of losses than wins in hospital mortality (1.1 vs. 0.9%) and hospital length of stay (33.8 vs. 33.2%), comparable percentages of losses and wins in postoperative invasive mechanical ventilation (0.2 vs. 0.2%), a higher percentage of wins in severe complications (2.5 vs. 2.1%) and a higher percentage of ties in mild complications (18.7 vs. 3.9% wins vs. 3.3% losses). The win ratio for high PEEP compared with low PEEP group was 1.00 (95% CI 0.92 to 1.09). No beneficial effects of high PEEP compared with low PEEP were found in this win ratio analysis. Clinicaltrials.gov (study identifier NCT03937375).

The role of promotions and other factors in attendance for minor league baseball – a study across all levels of play

PurposeThe main purpose of this research was to determine what types of promotions increase Minor League Baseball attendance across all of the official leagues. The secondary purpose was to ascertain the role of other control variables such as win percentage, weather, days of the week, start time and city demographics. The research also includes a grouping of cities through k-means clustering to better understand what types of promotions work in what cities.Design/methodology/approachData were gathered on all the Minor League Baseball teams and their respective cities. Regression models were run to test for the role of individual promotions (structured as dummy variables) and other controls. One model specification used city demographic variables, one used city fixed effects rather than city demographics and the final specification used k-means clustering to separate cities into distinct groups.FindingsPromotions generally were found to increase attendance, although there were differences across levels of play. K-means clustering helped with the grouping of cities to ascertain which types of promotions were beneficial when comparing large metropolitan areas to high-income cities.Research limitations/implicationsPromotions were grouped into common categories, although some were difficult to classify (or were infrequent), so a miscellaneous promotions category was included to capture these promotions in Minor League Baseball.Practical implicationsThe findings of this research are beneficial to those designing promotional schedules for individual teams. It also is beneficial to the leagues as the findings have implications as it relates to what fans desire to see when attending minor league games.Originality/valueThe originality in this work is the collection of all Minor League Baseball attendance, city information and promotional information across the different levels of play (AAA, AA, High-A and A). Using different model specifications and groupings, including k-means clustering to match similar cities, successful promotions were identified.

Home-Court Advantage and Home Win Percentage in the NBA: An In-Depth Investigation by Conference and Team Ability

The National Basketball Association (NBA) is the major professional basketball league in the United States. Home-court advantage (HA) and home win percentage (HW) have been identified as decisive factors in determining the final outcome of a game. This study analyzes a total of 24 regular seasons, with two main objectives: (i) comparing HA and HW within the two conferences and (ii) examining the influence of team ability on HA and HW. HA (%) was calculated as (total home wins/total wins) × 100, and HW (%) as (total home wins/total home games) × 100. Teams were categorized into four different groups based on their season win percentage using cluster analyses. Regarding the first aim, we used an Independent Samples T-test and Mann–Whitney to assess differences between conferences. Subsequently, we evaluated the second objective using one-way ANOVA or Kruskal–Wallis. The results indicated no significant differences in HA within conferences. However, Western teams tended to have a higher HW than Eastern teams. The analyses revealed significantly higher HA in contender teams compared to the rest of the team abilities (p < 0.001). High–medium-ability teams also showed a significantly higher HA (p < 0.001) compared to low-ability teams. However, non-significant differences were found between the remaining groups for HA. Regarding HW, we observed significantly higher values in the contender teams compared to the teams with other ability levels (p < 0.001). Additionally, the high–medium-ability teams also exhibited significantly higher HW values (p < 0.001) when compared to the medium–low- and low-ability teams. Furthermore, the medium–low-ability teams showed significantly higher HW values (p < 0.001) when compared to the low-ability teams. Those findings suggest that team ability influences HA and HW in the NBA, where contender teams have significantly higher HW and HA values compared to the teams with other team ability levels. Understanding these dynamics provides valuable insights for team strategies, particularly during playoff stages where home-court advantage can be critical for success.

Ranking in Incomplete Tournaments: The Generalized Win Percentage Method, Efficiency, and NCAA Football

I present a parsimonious family of scoring methods for ranking teams in incomplete tournaments. It is especially useful if teams play different number of games. I show that this family of scoring methods satisfies common sense theoretical properties studied by the literature on paired comparisons. I analyze it in terms of efficiency, defined as how close a scoring method comes to capturing what the teams’ win percentages would have been, in a complete tournament. Finally, using data on betting odds, I calibrate the family of scoring methods to match, as closely as possible, the actual rankings that were used to determine the teams that would go on to compete for the championship of the NCAA division 1 football tournament between 2011 and 2023. I find that the rankings used by the NCAA were generally efficient and I quantify the biases present in each year’s ranking.

Fairness mechanism and stackelberg strategy for multi-agent systems: A case study of legends of the three kingdoms

Alongside the rapid advancement of artificial intelligence technologies, the complexity of society continues to escalate, and the design of multi-agent system rules becomes increasingly crucial, optimize participant engagement and addressing the issue of fairness and equilibrium win rates. The card game Legends of the Three Kingdoms (LTK), as a complex multi-agent system, represents an important abstraction of real-world scenarios, requiring the implementation of proper incentive mechanisms. Based on the mechanism and Stackelberg, this paper optimizes player strategies and system fairness. Firstly, we constructed a multi-agent Stackelberg game model for team battles. Then, we analyzed the impact of decision-making factors on players. Subsequently, we defined three kinds of fairness and improved the incentive mechanism. The results indicate that our mechanism optimizes participants' game behaviors, enhancing fairness among team players. Win rates were improved from 56.2% VS 43.8% to 51.4% VS 48.6%. With three different fairness measures, the win percentage fairness increased by 72 %, and the first elimination fairness increased by about 79 %. Our research provides a reference for understanding and analyzing complex computational models and facilitates the resolution of various resource allocation and system design issues.

Intimate relationships regulate female brain activity in a competitive context: evidence from EEG and functional connectivity analysis.

Competition is common in life, and intimate relationships are essential. Understanding how intimate relationships impact an individual's competitive process is crucial. This study explored the impact of competitor gender on female competition using electroencephalography analysis. The results revealed that females exhibited a smaller median of the absolute value of reaction time difference (DRT) between their partners and their competitors when their partners were absent compared to when their partners were present. Additionally, females showed greater average amplitudes of N2 posterior contralateral component (N2pc) and Late Positive Potential (LPP), increased activation of the alpha frequency band, and enhanced theta frequency band functional connectivity between the central parietal lobe and occipital lobe. Furthermore, when competing with individuals of the same gender as opposed to individuals of the opposite gender, females exhibited greater average amplitudes of percentage of wins and N2pc. A significant negative correlation was noted between the DRT and the average wave amplitudes of N2pc and LPP. These findings suggest that females are more engaged in competitive tasks when partners are not present and have improved decision-making when competing with same-gender individuals. This study provides evidence for the influence of lovers on female competition, helping females adapt to social competition and promoting healthy relationships.

Defensive Performance Declines in Ultimate Fighting Championship Fighters Following Anterior Cruciate Ligament Reconstruction

PurposeThe purpose of the present study is to evaluate the impact ACL reconstruction (ACLR) has on strike evasion rates, strike and landing rates, win percentage, and career longevity in UFC fighters. MethodsUFC fighters who underwent ACLR from 1993-2022 were matched 2:1 with uninjured controls. The percentage of each injured fighter’s career that occurred before ACLR was deemed the “index percentage.” Injured fighter performance pre-/post-ACLR was compared to control metrics pre-/post-index percentage. ResultsA total of 82 subjects with documented ACL injuries were identified. There were 48 who met the inclusion criteria. Of these, 27 returned for more than 2 fights and were paired with 54 controls. UFC fighters demonstrate return-to-sport rates of 81.25% and 56.25% for at least one and two fights, respectively. On average, it took 411.85±174.73 (range, 165-879) days for fighters to return. All fighters had significantly lower evasion rates against total significant strikes, distance strikes, and head strikes, post-index; p<0.05 for each. ACLR fighters had significantly lower submission attempts and evasion rates against clinch strikes, ground strikes, and total strikes, post-index; p<0.05 for each. Controls had a significantly lower evasion rate against leg strikes, post-index. Both groups’ win percentages significantly declined (ACLR p=0.001, control p=0.012). No significant difference in total career fights was observed (p=0.873). ConclusionsIn this study, we found that most UFC fighters who undergo ACLR return to sport for at least one fight; however, just over half return for at least two fights. There was not a significant difference in career length between fighters who returned to sport following ACLR for at least two fights and their controls. Defensive performance, but not offensive performance, declined significantly following ACLR. All fighters demonstrated significant declines in their win percentage as their career progressed, irrespective of ACLR.

Home-Court Advantage is Greater for Teams Competing at Higher Playing Levels: An Exploratory Analysis of Spanish Male Basketball Leagues.

This study aimed to (i) compare the extent of home-court advantage (HA) and home win percentage (HW) between Spanish basketball leagues across different playing levels (i.e., leagues) and (ii) analyze the influence of team ability on HA and HW within each playing level. We gathered data for game locations and results from open online sources for all games in the First Division (ACB), Second Division (LEB Gold), and Third Division (LEB Silver) Spanish male basketball leagues between 2010-2023. The dataset included 12 seasons, 635 teams (215 First Division, 203, Second Division, and 217 Third Division), and 19,539 games (7075 First Division, 6344 Second Division, and 5520 Third Division). We calculated HA [(total home wins/total wins) * 100] and HW [(total home wins/total home games) * 100] for each team across each season. We performed Kruskal Wallis tests, calculated partial eta squared (ηp2), and performed Mann-Whitney U tests with rank biserial correlation (rb) effect sizes and Dwass-Steel-Critchlow-Fligner pairwise comparisons to compare HA and HW between leagues and between team abilities (low, medium, and/or high) within each league. There was a significant effect for HA between leagues (p = .01) with post hoc comparisons revealing a higher HA for the First Division than for the Third Division (p = .01), but HW was not significantly different between leagues. In turn, variations in HA and HW between team abilities were consistent across playing levels, with HW significantly increasing in a progressive manner with higher team abilities (p < .001) and with HA significantly lower among high-level teams compared to lower-ability team clusters (p < .01). These findings emphasize the importance of considering playing level and team ability and interpreting HA and HW together to contextualize an apparent home advantage in Spanish basketball.

Examining the Role of Fan Support on Home Advantage and Home Win Percentage in Professional Women's Basketball.

Our main aim in this study was to analyze any differences in Win Percentages at Home (HW) that might represent a Home-Court Advantage (HA) in women's professional basketball. A secondary objective was to analyze how team ability might modify the HA effect by comparing any interaction effect between HW and team ability in games played with and without fans. We collected data from first Spanish female basketball divisions, using a linear mixed model (LMM) for repeated measures to identify differences between time periods (games with fans vs. games without fans) for HA and HW. When comparing games with and without fans, we found no significant HA and HW differences (p = .283 and p = .872, respectively). In fact, interestingly, we observed higher win values when fans were absent. Additionally, during the COVID-19 shut down stage, HA increased; but it returned to pre-pandemic levels afterward, with no significant differences between these periods (p = .482). Similarly, while HW seemed to increase during the COVID-19 shut down period and continued improving in the post-pandemic phase, there were actually no statistically significant differences (p = .772). Higher HA and HW were evident without fans during the pandemic compared to the pre-pandemic period when fans were present in women's professional basketball. During the post-pandemic period, HA decreased upon fans' return, while HW continued increasing. We discuss possible bases for these unexpected findings.

The role of football win percentage on college applications for power five and group of five schools

AbstractInvesting in athletics is one approach that universities have taken to better appeal to potential students. We analyze whether football success, as measured by win percentage, is correlated with a higher number of student applicants. We find that for schools in the major “Power‐Five” conferences, win percentage does not significantly change the number of students who apply. However, in the smaller “Group‐of‐Five” conferences, win percentage is associated with an increase in the number of applications. This is a particularly relevant finding because smaller universities may often be the ones struggling to maintain the size of their student body.

Is there no place like home? home-court advantage and home win percentage vary according to team sex and ability in Spanish basketball

ABSTRACT To compare the extent of home-court advantage (HA) and home win percentage (HW) based on sex and team ability in Spanish basketball leagues. Data from the first divisions of male and female basketball over 12 seasons (2010-2023) were analyzed. HA (%) was calculated as (total home wins/total wins) * 100 and HW (%) as (total home wins/total home games) * 100. Teams were categorized into higher-and lower-ability based on their season win percentage using cluster analyses. Mann-Whitney test was used to compare HA and HW between sexes and team ability clusters. Results showed that males exhibited higher HA and HW compared to females (p < 0.05). Additionally, males had higher HA than females within both higher- and lower-ability teams (p < 0.05) and higher HW only within lower-ability teams (p < 0.001). Lower-ability teams had higher HA than higher-ability teams (p < 0.001). while higher-ability teams had higher HW (p < 0.001). These findings suggest that team sex and ability significantly influence HA and HW effects in Spanish basketball leagues. Female teams demonstrate a more even distribution of wins between home and away venues, while lower-ability teams rely more on home games for wins. Understanding these effects can aid in developing strategies tailored to sex and ability among Spanish basketball teams.

Association of Win-Loss Record With Neuropsychiatric Symptoms and Brain Health Among Professional Fighters.

Repetitive head impacts in professional fighting commonly lead to head injuries. Increased exposure to repetitive head trauma, measured by the number of professional fights and years of fighting, has been associated with slower processing speed and smaller brain volumes. The impact of win-loss outcomes has been investigated in other sports, with several studies suggesting that individuals on losing teams experience more head injuries. Here, the authors hypothesized that fighters with a worse fight record would exhibit poorer brain health outcomes. The Professional Fighters Brain Health Study examined changes in neuropsychiatric symptoms, regional brain volume, and cognition among professional boxers and mixed martial arts fighters. These data were used to evaluate the relationship between win-loss ratios and brain health outcomes among professional fighters (N=212) by using validated neuropsychiatric symptom and cognitive measures and MRI data. Retired fighters with a better record demonstrated more impulsiveness (B=0.21, df=48) and slower processing speed (B=-0.42, df=31). More successful fighters did not perform better than fighters with worse records on any neuropsychiatric or cognitive test. Retired fighters with better fight records had smaller brain volumes in the subcortical gray matter, anterior corpus callosum, left and right hippocampi, left and right amygdala, and left thalamus. More successful active fighters had a smaller left amygdala volume. These findings suggest that among retired fighters, a better fight record was associated with greater impulsiveness, slower processing speed, and smaller brain volume in certain regions. This study shows that even successful fighters experience adverse effects on brain health.

Does Air Travel Adversely Affect Team Performance in Major League Baseball?

Previous studies of the effects of air travel on team performance in baseball focused on jet lag, namely, teams that traveled across at least two time zones between games. But baseball teams that travel extensively up and down either the West or East Coast do not cross one (let alone two) time zones. For the years between 2019 and 2022 (including the COVID-19 pandemic-shortened 2020 season), the authors relate the difference between a team’s season-long winning percentage at home less its winning percentage on the road to the total regular season-long number of miles traveled for the 15 teams in each league. Save for a pair of teams in the American League in 2020, the authors find that there is no statistically discernible relationship between the number of miles traveled per season and the difference between home and away team win percentages.

High Compliance with the 11+ Injury Prevention Program Results in Better Win-Loss Records.

The 11+ injury prevention program (IPP) has been shown to decrease injury rates. However, few studies have investigated compliance and its overall relationship to team performance. To examine if level of compliance while implementing the 11+ would impact team performance outcomes (wins, losses and ties). The authors hypothesized that higher team compliance to the IPP would be consistent with improved overall team performance (more wins and fewer losses). Prospective, cluster randomized controlled trial. This study was conducted in NCAA men's soccer teams for one season and examined the efficacy of the 11+ IPP. The outcome variables examined were levels of compliance and team performance record: wins, losses, and ties. Twenty-seven teams (n=675 players) served as the intervention group (IG) and used the 11+ program while 34 teams (n=850 players) served as the control group (CG). Compliance and team performance were recorded. There were three compliance categories that were defined prospectively, low (LC, < 1 dose/week), moderate (MC, >1 and <2 doses/week), and high (HC, >2 doses/week). Descriptive and inferential tests were used to compare the CG, the IG, and compliance to team performance. Three independent t-tests were used to analyze outcome to group (IG vs.CG). A one way-MANOVA test was used to analyze compliance to win/loss/tie record, followed up by one-way ANOVA tests to analyze how compliance impacted wins, losses and ties, independently. Partial η2 measures were calculated to determine the effect size of level of compliance on outcome. A Tukey post-hoc analysis was used to analyze specific differences between levels of compliance and specific outcome measures. There were significantly more wins (IG: 10.67±2.63 versus CG: 8.15±3.83, CI, 7.95 - 9.69, p = 0.005) and fewer losses (IG: 5.56±1.97 versus CG: 8.12±3.59, CI, 5.66 to 7.43, p = 0.002) recorded for the teams using the 11+ program. There was a statistically significant difference between levels of compliance (high, moderate or low) on the dependent variables (wins, losses, and ties), F(3, 22) = 3.780, p =0.004; Wilks' Λ = .435; partial η2 = .340. The 11+ has the capacity to improve overall team performance in male collegiate soccer teams. The higher the compliance, the more favorable the team performance. This research may be a vital addition when attempting to persuade coaching staffs to adopt an IPP into their training regimen. Level I.

Production functions of NCAA men and women water polo matches

Previous research has adapted the use of economic production functions to estimate the scoring production of teams in professional sports. Most of these studies have focused on professional male team sports, most notably, US baseball, basketball, and association football. This study adds to the literature by utilizing a new and distinctive data set of shooting statistics from 88 men’s and 38 women’s NCAA water polo contests to estimate production functions for United States’ collegiate water polo games and identify the most important variables for predicting margin of victory in such competitions. The results show that shots on goal, average shot distance, number of counterattacks, quick shots, and efficiency in power play conversions are all significant predictors of goal differentials in men’s contests while shots on goal, average shot distance, counterattacks, and center shots are significant predictors in women’s matches. Previous season win percentage, rebounds, exclusions, and missed shots were not significant predictors in the models. These conclusions confirm and extend previous discriminatory studies of elite international water polo contests.

Winning a CHSH Game without Entangled Particles in a Finite Number of Biased Rounds: How Much Luck Is Needed?

Quantum games, such as the CHSH game, are used to illustrate the puzzle and power of entanglement. These games are played over many rounds and in each round, the participants, Alice and Bob, each receive a question bit to which they each have to give an answer bit, without being able to communicate during the game. When all possible classical answering strategies are analyzed, it is found that Alice and Bob cannot win more than 75% of the rounds. A higher percentage of wins arguably requires an exploitable bias in the random generation of the question bits or access to "non-local" resources, such as entangled pairs of particles. However, in an actual game, the number of rounds has to be finite and question regimes may come up with unequal likelihood, so there is always a possibility that Alice and Bob win by pure luck. This statistical possibility has to be transparently analyzed for practical applications such as the detection of eavesdropping in quantum communication. Similarly, when Bell tests are used in macroscopic situations to investigate the connection strength between system components and the validity of proposed causal models, the available data are limited and the possible combinations of question bits (measurement settings) may not be controlled to occur with equal likelihood. In the present work, we give a fully self-contained proof for a bound on the probability to win a CHSH game by pure luck without making the usual assumption of only small biases in the random number generators. We also show bounds for the case of unequal probabilities based on results from McDiarmid and Combes and numerically illustrate certain exploitable biases.

Cross-Quality Impacts of NCAA Division I Baseball and Softball

Fifty years after Title IX, inequalities still exist between men's and women's sports. Most sport studies still fail to examine women's sports. This study explores the cross-quality impacts of Division I baseball and softball teams. The softball team win percentage is positively related to softball and baseball game attendance. However, models produce mixed results for the impact of the quality of the baseball team. Therefore, improving the strength of the softball team could increase softball and baseball game attendance, while improving the strength of the baseball team might only increase attendance at baseball games.

Calculating expected win percentage of an Indian Premier League team

The Indian Premier League is the most prestigious cricket league globally. There are significant finances in terms of both team ownership and player salaries. It is, therefore, essential to understanding if a team’s record is due to luck (good or bad) or if a team’s record is due to the team’s overall performance. The research presented here is motivated by how to accurately predict a team’s winning percentage in the Indian Premier League based on underlying statistics. A similar analysis has been done in other sports, mainly based on the concept of the Pythagorean expectation. This research derives a similar model for the IPL based on historical data. However, the structure of a match in the Indian Premier League is fundamentally different than the structure of games in other sports. As a result of this structural difference, this study creates additional models using both least absolute shrinkage and selection operator and stepwise regression to identify variables that are good predictors for calculating the expected winning percentage. These models compare favorably to the Pythagorean expectation model. This article presents a model combining both the determined variables and Pythagorean expectation.

Market Efficiency and Censoring Bias in College Football Gambling

The team totals and point spread betting lines jointly predict team scores in college football games. The gambling market’s score predictions are shown to be biased due to censoring at zero points. This presents arbitrage opportunities for gamblers who place wagers on the team totals line in cases for which expected bias is high. A naïve betting strategy that exploits this bias using only information contained within the two betting lines themselves yields a win percentage of over 55 percent over the past two decades. This significantly exceeds the typical transaction costs associated with wagers, indicating the market is semi-strong inefficient.

An Analysis Of In-game Collegiate Baseball Hitting Performance Following Sports Vision Training

Vision training (VT) programs can be utilized to enhance perception and eye-hand coordination to potentially improve sports performance. There is general support for VT improving athletic performance, but limited research is present for in-game performance improvements, particularly for collegiate baseball. PURPOSE: To evaluate for potential benefits of a VT program on collegiate baseball team hitting performance. If beneficial, VT may be used to supplement standard baseball practice to further improve hitting performance. METHODS: The Northwestern College (NWC) varsity baseball team, a member of the NAIA Greater Plains Athletic Conference (GPAC), performed VT exercises including Brock string, King-Devick test for saccades, long-distance saccades, and near-far training in 18 sessions during the 2019 season. In-game hitting statistics for the 2018 and 2019 seasons were retrospectively collected for all GPAC teams. Two-proportion z-tests were used to compare batting average and slugging percentage between NWC and the GPAC during the 2018 and 2019 seasons. RESULTS: The overall win-loss record of NWC was 30-20 in 2018 (1st place) and 23-25 in 2019 (6th place). Three starting hitters from the 2018 team remained on the team for the 2019 season. The 2018 GPAC batting average was .280 and NWC’s was 6th in the conference at .288 (p = .261). The 2019 GPAC batting average was .281 and NWC led the conference at .304 (p = .034). Batting averages for the GPAC and NWC did not differ between the 2018-19 seasons (p = .417 and p = .171, respectively). The 2018 GPAC slugging percentage was .388 and NWC was 3rd in the conference at .423 (p = .005). The 2019 GPAC slugging percentage was .393 and NWC was 2nd in the conference at .435 (p = .001). The slugging percentages for the GPAC and NWC did not differ between the 2018-19 seasons (p = .233 and p = .261, respectively). CONCLUSIONS: The team batting average was significantly better than the conference average during the season with VT despite losing six starting hitters from the prior season. These differences were not observed in the season before VT. Slugging percentage improved only minimally with VT. These outcomes suggest that VT may improve the in-game batting performance of collegiate baseball players and confirm previous research on the effects of VT on collegiate baseball hitting.