The previous Maekawa et al.’s⁹⁾ investigation on the validation of competitive abilities scale of judo competitors determined nine items such as general motor ability, mental toughness, attention to form, stamina, tactics, assertiveness of the athlete in applying kumi-te, proper kumi-te style, standing defense, and mat skills. The aim of this study is to develop a scale on competitive ability and to verify the validity of the scale by using Analytic Hierarchy Process (AHP) based on those nine items. As a result, data ranked by the total score of the competitive ability scale had a high correlation with predicted competition results by AHP (respectively, p<0.001, for all; Spearman’s Rank Test).
Thus, this study showed that the scale on competitive ability was effective by using AHP.

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スポーツの試合での最初の得点は，最終結果に影響を及ぼす可能性がある重要な指標である。本研究で，我々は，最初の得点の影響力を測定するために，多くの柔道の試合を分析した。これは，選手の心理的覚醒レベルの指標とみることが可能である。この効果を評価するために，我々はこれまでの何年かの試合で採用された審判規定に従って収集データを処理した。2008年において，国際柔道連盟（IJF）は競技規定を改定し，「効果」の最少ポイントを廃止し，結果として最初に「指導」を受けると与えられる等価のポイントも廃止した。我々は，実際の柔道の試合から競技データを収集し，最初にポイントを取られることが選手の心理状態に影響を及ぼし，そのため最終結果が影響を受けるということがあるどうかを確かめることができるように，競技データをその試合で採用された規定に基づき分類した。データを統計的に検定したところ，本研究の結果は，最初にポイントを取られることは結果に重要な影響を及ぼすことを示した。

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The All-Japan Judo Championships (AJJC) is an open-weight tournament for determining the best judoka in Japan. The AJJC has been held under the Kodokan Judo Refereeing Rules (KDK Rules) since 1951. In 2011, the All-Japan Judo Federation (AJJF) introduced the International Judo Federation Refereeing Rules (IJF Rules), which were formulated to facilitate more dynamic judo (increased wins by ippon, decreased wins by judges’ decisions, and decreased mate-time). Although the IJF Rules has facilitated dynamic judo in international competitions, their effects on the competition contents in the AJJC are still unknown. Here, we aimed to clarify whether the introduction of the IJF Rules facilitated dynamic judo in the AJJC.
The 221 judo matches in the AJJC from 2008 to 2013 were separated into two groups, the tournaments following the KDK Rules (2008-2010) and those following the IJF Rules (2011-2013). Their data were extracted from the AJJC records by Judo, the official Kodokan journal, and from the match videos recorded by the AJJF. We analyzed the proportions of winning contents (wins by ippon or superior performance), winning methods (points from techniques or penalties, or judges’ decisions), techniques for getting points (te-waza, koshi-waza, ashi-waza, sutemi-waza, or katame-waza) and the mate-time for each match. A chi-square test and an independent t-test were used to perform statistical analyses, and for each test, statistical significance was assumed at P value < 0.05.
For the winning methods of the IJF Rules’ and the KDK Rules’ tournaments, the proportion of points from techniques (60.4% vs. 53.6%) and points from penalties (23.4% vs. 15.5%) showed no differences, but the proportion of wins by judges’ decisions in the IJF Rules’ tournaments was significantly lower than in the KDK Rules’ tournaments (16.2% vs. 30.9%) (P < 0.05). Furthermore, the mate-time in the IJF Rules’ tournaments was significantly shorter than in the KDK Rules’ tournaments (77 s vs. 105 s) (P < 0.01). However, the winning contents and techniques for obtaining points showed no differences between the IJF Rules’ and the KDK Rules’ tournaments.
We confirmed for the first time that the IJF Rules did not affect the winning contents and techniques for getting points, but decreased the proportion of judges’ decisions and mate-time in the AJJC. These findings suggest that the IJF Rules partially facilitated dynamic judo in the AJJC.

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本論文は，情報力学モデル（ξ＝η^m，ここで，ξは試合結果の確かさ，ηは無次元試合長さ，そしてmは正の実数）を用いて柔道の試合を解析したものである。ここで，提案された解析方法は柔道の試合を分析するにあたり非常に有用であることが判明したので，柔道指導者のみならず，柔道選手が彼らの技能を高めるために本モデルを活用することができる。情報の分野に力学を導入することの有用性は，第5回，並びに第6回世界柔道選手権における二つの決勝戦を解析することにより証明された。本研究を通して，試合結果の確かさと試合結果の不確かさを表す二本の曲線の交点において，試合結果が決まるという新たな知見が得られたので，この点を特に，“ゲーム・ポイント”と名づけ，これら二つの試合の分析を行った。

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In the present study, 104 collegiate judokas (competitive level: international, n＝26; national, n＝26; regional, n＝26; prefectural, n＝26) who had no refereeing experience watched and subsequently evaluated video footage of four types of throwing techniques recorded from four different directions. We then investigated whether conflicting evaluations or similar effects would arise among the judokas based on their competitive level. We obtained the following results.
1．No significant interactions were observed for any of the throwing techniques, indicating the absence of complex factors involving mutual interaction between viewing direction and competitive level.
2．A significant main effect was observed for the viewing direction for all four throwing techniques, indicating a relationship with the occurrence of conflicting evaluations across all competitive levels.
3．For two of the four throwing techniques, a significant main effect was observed for competitive level, indicating a high possibility that this factor is related to the occurrence of conflicting evaluations.
4．International-level judokas gave significantly more favorable evaluations for ippon-seoi-nage (one-arm shoulder throw) than prefectural-level judokas.
International-level judokas also tended to give significantly more favorable evaluations for osoto-gari (major outer reaping throw) than both regional- and prefectural-level judokas. These results suggest that conflicting evaluations of throwing techniques are likely to occur when the judokas performing the evaluations are separated by two or more competitive levels. The results also suggest that judokas competing at higher levels evaluate throwing techniques more favorably than those competing at lower levels.
Based on the above, conflicting evaluations of throwing techniques occur according to the viewing direction, even when those evaluating the techniques compete at the same level. This indicates that viewing direction is a primary cause of conflicting evaluations of throwing techniques, and thus that conflicting evaluations are inevitable. It is therefore important for judges to view throwing techniques from multiple directions. In addition, conflicting evaluations occur due to differences in the competitive level of the referees; therefore, it is important for those wishing to become referees to first compete at a high level as judokas.

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