Objectives: The purpose of this investigation was to evaluate the intra- and intersession reliability of a new inertial measurement unit (ZEPP Sensor (ZS)) for bat swing mechanical analysis. Design and Methods: This investigation included 16 male collegiate baseball players (89.53 ± 12.5 kg, 180.61 ± 6.5 cm, 20.12 ± 0.8 years). Following a whole body dynamic warm-up and 5 dry swings, 5 swings were recorded where athletes hit balls off of a tee with bats instrumented with a ZS. Data collection took place on 3 days. Intrasession reliability analyzed trial to trial data, while intersession reliability analyzed data from each of the 3 sessions. Both relative and absolute measures of reliability were calculated with intraclass correlation coefficients (ICC), coefficients of variation (CV), and limits of agreement (LOA). Results: Within and between session acceleration/time related variables produced excellent relative reliability measurements (ICCs 0.882-0.988) as well as acceptable absolute measures of reliability (CVs 1.9%-9.2%). Variables derived from the gyro scope did not display the same consistency (intrasession vertical angle ICC = 0.492, intersession attack angle CV = 108.6%). Conclusions: Considering acceleration/time data, the ZS appears to be a reliable method of monitoring bat swing mechanics, but not for the angular position variables. Changes in body position have been demonstrated with fatigue in jumping performance. Similarly, bat position changes may occur with fatigue and should be monitored, but coaches and sport scientists should use caution when selecting variables to monitor and only select those that are reliable.

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In professional baseball games, the timing of changing the starting pitcher is an important factor in winning a game. The exploitation of various sources of data was recently enabled. Thus, it is desirable to develop an effective analytical model for team management that learns from past data. In this study, we propose a statistical model to estimate the expected runs for each inning and support decision-making on changing starting pitchers. Specifically, we developed a Markov chain model with a transition probability matrix for states defined by the combination of out counts and occupation of the bases. Note that the transition probability between the pitcher and batter can vary depending on the match. However, even if the transition probabilities are estimated for each match, the number of combinations becomes very high, and the estimation accuracy is reduced. Therefore, we introduce a latent-class model to estimate the transition probabilities while grouping the combinations into a small number of latent variables. Using the proposed model, it is possible to estimate the expected runs accurately by using the transition probabilities estimated for each latent class. To verify the effectiveness of the proposed model, we conducted experiments using actual Japanese professional baseball data.

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Background : Research on the effects of disaster-relief by professional athletes has yet to be conducted.
Methods : We investigated the impact of continuous sports lessons, by professional athletes, on the mental and physical health of the participants and the athletes. The participants were high school students of Soma High School. Lessons started in June 2011 ; as of August 2012, seven lessons have been held. During the four lessons between September and December 2011, we collected qualitative and quantitative data by recording each student’ s event records and distributing a free response questionnaire to students and athletes.
Results : Participants included 45 students and 16 athletes. All the students established new event records. Numerical evaluation by students on perceived physical competence, self-efficacy, and perception of organizational changes failed to show any significant changes, while subjective evaluation by students identified three important categories : “ emotional response” , “ motivation” , and “ content of instruction” . Both students and athletes developed their interpersonal relationships from distant to close, and perceived enhancements in their psychological state during study periods.
Conclusions : A trusting relationship was established between students and athletes through continuous sports lessons held in disaster stricken regions, contributing to fruitful outcomes for both students and athletes.

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The purpose of this study is to examine the role played by the technological development of TV satellite transmissions on the rapid expansion of sport economy in the United States in the 1970s and 80s. The satellite transmission technology, especially the adoption of Ku-band frequencies, created ‘superstations’ and put an end to the exclusivity of the nationwide land-line networks by the ‘Big Three’ TV Networks. Thousands of isolated cable systems managed to receive programmes from other areas of the country via these superstations due to the creation of these satellite networks. Owing to the new networks, the number of the nationally televised sports games/matches drastically increased, most of which used to be only broadcast locally. Accordingly, the price of broadcast rights, the ad-boards, and merchandising increased. In conclusion, the rapid expansion of the sport economy in the US was caused by the technological innovation of satellite transmissions, and this process occurred between approximately 1978 and 1984.

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The purpose of this study is to evaluate management efficiency of professional teams in the Korean Baseball Organization by using Data Envelope Analysis (DEA). The professional baseball teams in Korea are in urgent need of efficient management as no teams are making profits and their financial deficits are growing. DEA is a technique to measure relative efficiency when coping with multiple inputs and multiple outputs. We implemented total player salary as input item and winning percent and total fan attendance as output item to evaluate 8 teams' management efficiency for the 2004 season. The analysis identified teams operating relatively efficient and teams that are not efficient. The result revealed that a team's efficiency score is not necessarily correlated to the final standings in the league. Rather, teams relatively mediocre sized outperformed the teams well-known for its financial abundance.

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Pacific league teams have been the champion teams in the NPB for the recent eight years, and ability differences among the relievers in both leagues have been noted. Major determinants of team wins during the regular season might be different between both league teams. To explore the determinants of win rate in each league, the current study analyzed team stats. Two major findings associated with baseball stadium size were found. First, central league teams can offset poor pitching performance by batting, although the effect of good pitching on team wins among central league teams is smaller, compared to that of pacific league teams. Second, increasing the number of stolen bases per game does not have a significant effect on team wins. Pitchers in the central league teams should improve pitch mix to reduce the number of home runs allowed per game.

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症例は2型糖尿病と肝硬変にて加療中の70歳女性．身長149.0 cm, 体重43.7 kg. 服の上から直接インスリン注射をする大リーガーを見て，自分もお腹を出して直接注射してみた．注射直後からその部に疼痛が出現し，めまいが起こり，3時間後には意識を消失した．救急病院へ運ばれ，検査の結果，著明な貧血のほか，腹部に広範な皮下出血と注射部直下に巨大皮下血腫(8×11×4.5 cm)が確認された．この大出血の原因には患者が痩せていたことに加え，合併する肝硬変による血小板数減少と，用いたインスリン注入器（ヒューマカート^®キット）の注入抵抗の問題が考えられた．最近では，衣服の上から注射しても安全であるという報告が多く見られる．しかし，本例のように，痩せ型で肝硬変のような合併症を伴う場合には，インスリンデバイスの選択を含め，原点に帰った慎重なインスリン注射指導を行う必要があると考え報告した．

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This paper introduces a technique for automatically generating potential training data from sentences in which entity pairs are not apparently presented in a relation extraction. Most previous works on relation extraction by distant supervision ignored cases in which a relationship may be expressed via null-subjects or anaphora. However, natural language text basically has a network structure that is composed of several sentences. If they are closely related, this is not expressed explicitly in the text, which can make relation extraction difficult. This paper describes a new model that augments a paragraph with a “salient entity” that is determined without parsing. The entity can create additional tuple extraction environments as potential subjects in paragraphs. Including the salient entity as part of the sentential input may allow the proposed method to identify relationships that conventional methods cannot identify. This method also has promising potential applicability to languages for which advanced natural language processing tools are lacking.

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The Meiji Jingu Baseball Stadium attracts a large number of spectators in the Tokyo metropolitan area. To clarify the demand for medical care at a public ballpark, we analyzed following two types of medical records maintained at the stadium: (1) "Report of Aid": a record of patients visiting the first-aid station in 2003 season and (2) "Report of Accidents": a record of patients referred to clinics/hospitals between 1996 and 2003 season. (1) In 2003, approximately 1,582,000 spectators watched 67 professional baseball games (60 night games). Of the 247 spectators received medical care at the first-aid station (3.7 persons per game, 1/6,405 spectators), 128 (51.8%) had trauma and 109 (44.1%) had illness. The incidence of trauma was relatively higher before the start and near the end of the night games. The risk of becoming sick/wounded per spectator or the number of the sick/wounded per game differed depending on the participating sports teams. (2) Ninety-three spectators referred to clinics/hospitals during the 8-year period from 1996 to 2003, of which 57 were transferred by ambulance. Direct ball injury accounted for 65 (69.9%) cases of trauma, followed by stumbling/falls (18 cases, 19.4%). Twenty patients were diagnosed to have fractures at the clinics/hospitals. Intrinsic cardiopulmonary arrest occurred in one spectator. Trauma due to direct ball injury accounted for the largest number of wounded patients referred to clinics/hospitals. Treatment to patients at the first-aid station in the stadium may optimize the frequency of hospital visits. Records of medical care are effective to analyze the demand for medical preparedness.

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Abstract The home advantage has been popular phenomenon in sport. However, very little systematic research has been carried out in Japan. The purpose of the present paper is to provide an empirical evidence of the home advantage in the Nippon Professional Baseball （NPB）. The results revealed that home winning percentage in the NPB was 55.3%. There were no differences in degree of home advantage between the NPB and the

（MLB）. We discussed four factors thought to be responsible for home advantage.

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Objectives: The purpose of this study was to examine the relationship between lower-body power output and pitching velocity in professional baseball pitchers. Design and Methods: A cross-sectional design was used to assess twenty-seven minor league baseball pitchers were for lower body power output using two methods. Countermovement vertical jump (CMVJ) and a 30 second sprint cycling test (Cycle) were used to calculate peak and mean power, as well as normalized peak and mean power respectively. Additionally, peak velocity, and mean velocity was assessed during the CMVJ with the use of a linear position transducer attached to a wooden dowel. Pitching velocity was measured as the greatest fastball pitch velocity for each subject recorded during a minor league spring training game. Mean velocity was that of all fastballs thrown. Pearson product-moment correlation coefficients were used to analyze the relationship between all variables with alpha levels set at p < 0.05. Results: Mean power during Cycle showed a significant positive relationship to both peak and mean throwing velocities (r = 0.441 and 0.428, respectively). Conclusions: Sprint cycling performance and more specifically the mean output over the duration of the sprint has a significant linear relationship with both peak and mean throwing velocity in professional baseball pitchers.

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Opposing clubs involve not only sports competitors but also economic partners that are likely to influence fan behavior. Therefore, it is important to understand rivalry in team sports to ensure the financial viability of the leagues and teams. However, much of the study on rivalry in sports has focused either on professional or high-level men’s collegiate team sports in the US. The research in this study explored the perceptual rivalry of a Japanese professional sport club’s supporters against other clubs and the reasons for the rivalry. Data were collected via an email survey of the official fan club members of Alvark Tokyo, a Japanese professional basketball team in the B.League (N=377). Respondents were asked to rank up to five of the biggest rival clubs in the B.League first division and assess their subjective intensity of rivalry on a 100-point direct rating scale (RP). Next, they were asked to answer the reasons for their rivalry perception, based on 17 rivalry element items. The intensity of the rivalry against each club was calculated as the average value of the RP. A Kruskal-Wallis test was used to assess the differences in the reasons why each club was recognized as the biggest rival. The Chiba Jets was selected as the biggest rival team (RP=84.0), followed by the Tochigi Brex (RP=82.1), the Ryukyu Golden Kings (RP=61.2), the Kawasaki Brave Thunders (RP=56.0), the Seahorses Mikawa (RP=27.4), and the Sunrockers Shibuya (RP=16.9). The Kruskal-Wallis test indicated that the reasons for supporters’ perception of rivalry differed significantly across the six clubs. The empirical results suggested that the rivalry against other clubs may be amplified by the overlapping of conditions such as comparable competitiveness, geographical proximity, and historical relationships. Some practical implications are provided.

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will examine the question of the relationship between sports and shared community living through the analytical lens of baseball. It will set forth five prerequisites for baseball. Baseball’s diffusion and widespread acceptance and use that theoretical framework to elucidate the significance of the franchise system in , Japan’s colonial rule in Taiwan, Manchuria, Korea, and Japan’s high school amateur baseball and professional baseball. Additional, the paper will highlight the Olympic Games, World Baseball Classic (WBC) and Hand Hit-ball as case studies of Japan’s symbiotic relations with the world.

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The purpose of this study was to investigate the characteristics of physical fitness in baseball pitchers and infielders focusing on variations in power output ability and stretch-shortening cycle (SSC) ability in field tests.
Twenty-five male university pitchers and 22 university infielders participated. They performed five kinds of jumping (Standing triple jump (STJ), Standing double leg triple jump (SDTJ), Standing long jump (SLJ), Counter movement jump (CMJ), 5 rebound jumps (RJ)), and five kinds of medicine ball throw (Overhead throw (OT), Back throw (BT), Push of upper limb (Push), Shoulder horizontal adduction (SHA) and Twist of trunk throw (Twist)).
Push, SHA and Twist were performed purely concentrically (concentric throw: CT) and with SSC movement (rebound throw: RT). These powers were assessed using the Throw index (Tauchi et al., 2006), and pre-stretch augmentations (Walshe et al., 1996) were calculated. It was found that: 1) OT, BT and SDTJ in pitchers were significantly higher than in infielders, and that there were significant correlations between pitched ball speed and OT, BT, and SDTJ. 2) Push RT-index and Push CT-index in infielders were significant higher than in pitchers, and significant correlations were found between thrown ball speed, batted ball speed and Push RT-index and Push CT-index in infielders. 3) SHA augmentation in infielders was significantly higher than in pitchers, and there was a significant correlation between thrown ball speed and SHA augmentation in infielders. 4) Twist of trunk power did not differ between pitchers and fielders.
These results indicate that baseball pitchers and infielders obtain different physical fitness characteristics through the differences in their movement forms and required abilities.

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A method has been developed for automatically classifying baseball video scenes into some events that describe their content.The baseball scenes are patternized using a set of rectangles with image features and motion vectors.The basic unit for patternization is a shot.For the second shot of each scene which includes significant information for event-classification,a partial shot generated by dividing the shot is used as a processing unit.The scenes used for training are expressed as sequenced symbols based on the patternized data for shots and partial shots.“Event-unknown”baseball scenes are assigned “event-indexes”(i.e.,homerun,single,walk,etc.) using discrete hidden Markov models that have been trained with the training symbol sequences for each kind of event.An experiment using videos of seven games produced good results,demonstrating that this method can automatically classify events with high accuracy.

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To fully utilize the limited battery energy of mobile electronic devices, we propose an adaptive adjustment method of processing quality for multiple image stream tasks running with widely varying execution times. This adjustment method completes the worst-case executions of the tasks with a given budget of energy, and maximizes the total reward value of processing quality obtained during their executions by exploiting the probability distribution of task execution times. The proposed method derives the maximum reward value for the tasks being executable with arbitrary processing quality, and near maximum value for the tasks being executable with a finite number of processing qualities. Our evaluation on a prototype system shows that the proposed method achieves larger reward values, by up to 57%, than the previous method.

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