2020年春，国内におけるCOVID-19の感染拡大により，全国的に大学の授業がオンラインにて実施されるようになった．座学の授業であれば，オンライン授業でも十分な学習効果をあげられると考えられるが，体育実技の場合，そうはいかない．ましてや体操やヨガなどの道具を用いなくとも実施可能な内容ではなく，ゴールやボールを用いるバスケットボールの実技授業をオンラインで実施することは困難を極めた．本稿では，Zoomを用いたオンライン授業におけるバスケットボールの実践とその可能性について報告した．Zoomを用いたオンライン授業では，画面共有機能やチャット機能，「手を挙げる・降ろす」機能，ブレイクアウトルーム機能，ホワイトボード機能などのZoomに備わる各種機能の活用が有効であった．また，動画によるルールやスキルの説明が効果的であり，制限された環境下における動画作成では，可動式のマネキンやNBA 2Kの映像，LEGO，NBAプレーヤーのフィギュアの活用が有効であった．さらに，パーカーのアームとボディ部分を丸めてフードに詰め込み，紐を縛って作るパーカーボールの考案により，オンラインで実施可能な実技の幅が各段に広がり，ドリブルやパス，ショットの授業では各スキルを構成する要素を抜き出して実施した．今回のオンライン授業の成果は，バスケットボールの実技をオンラインで実施する可能性がいくらか見出せたことであろう．実際に受講生はオンライン上でボールを使って実技を行い，相手プレーヤーと駆け引きをし，味方プレーヤーとコミュニケーションをとり，チームメイトと協力してオフェンス戦術について思考を巡らせた．

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In basketball, fast-break and early-offense are called “progressive plays" because the ball is continuously advanced from the back-court through the front-court to the basket. In a progressive play, the preceding play and situation are related to the subsequent play and situation. The plays are not necessarily chosen freely due to the former play or situation. Plays and situations that are related to each other and are frequently performed in sequence are referred to as nagare in Japanese. This study aimed to extract the factors of nagare in a fast-break-aiming play with statistical procedures. We observed and evaluated 658 plays considered either fast-break or early-offense plays. These plays took place during 12 games between the RF team and 6 other teams in the same bj League (Japanese Professional Basketball League) held in 2009 and 2010. A total of 17 items such as “How the opponent's ball was taken away," “The number of defensive players putting pressure on the ball man when taking the ball," “Distance (length) from the end line to the place where the ball was taken away," and so on were assessed. As categorical and continuous scales were mixed in the data, a correlation matrix was computed using Pearson's correlation coefficient, a contingency coefficient, and a correlation ratio, respectively. The correlation matrix was factored by principal factor solution and orthogonal normal varimax rotation.

As a result, the following four nagare factors explained 61.2% of the total variance: (1) the nagare factor deciding the offensive play pattern in the front-court depending on the speed of conveying the ball in the back-court, (2) the nagare factor deciding the ball-conveying situation and the success of the fast-break depending on the ball-taking situation, (3) the nagare factor deciding the speed of conveying the ball in the back-court depending on the number of offensive players, and (4) the nagare factor deciding the success of shooting depending on ball-taking area, play after ball-taking, and shooting area.

After removing spurious correlations using a partial correlation, five paths with substantial significant correlations were found as follows:

(1) “How the opponent's ball was taken away" → “The difference in the number of offensive and defensive players when the ball went through the center line" → “Whether the fast-break was successful or not";

(2) “Distance (length) from the end line to the place where the ball was taken away" → “The difference in the number of offensive and defensive players when the ball went through the center line" → “Whether the fast-break was successful or not";

(3) “The number of defensive players putting pressure on the ball man when taking the ball" → “The difference in the number of offensive and defensive players when the ball went through the center line" → “Whether the fast-break was successful or not";

(4) “Distance (length) from the end line to the place where the ball was taken away" → “The number of players conveying the ball" → “Whether the fast-break was successful or not"; and

(5) “Distance (width) from the side line to the place where the ball was taken away" → “The play just after the ball was taken away" → “The shooting area" → “Whether the shooting was successful or not."

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    The purpose of this case report was to describe and study the author's experience with teaching the dribble layup to a beginning basketball player, and to provide knowledge that would help other coaches teach the technique. The beginning female player had problems making a smooth transition from the dribble step to the shooting step during the catch phase of the dribble layup, and had difficulty making a stable throwing motion. Therefore, the author proposed a step-by-step practice drill to promote the connection of the two skills of dribbling and shooting, and attempted to create a movement of kicking with the axle foot at the beginning of the shooting step and develop a rhythm when catching from dribbling. Based on the practice drill, the learner shouted “un” for the final dribble and “1, 2” for the shooting step, and got the hang of the movement of entering the step and timing it together with the shouts. The findings of this study highlight the importance of placing the point of awareness on the technique before the catch phase in order to make the connection between the dribble and the shooting step smooth. Knowledge gained from this report will be helpful to other coaches teaching beginners the dribble layup.

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The purpose of this paper is to clarify the domestic frozen-vegetable import market moving into the period of maturity from the growth phase. Taking the viewpoint of product life cycle theory, the paper analyzes three points! sales figures, selling price, and cost. The trend of import value reveals the development importer's purchase price. The research shows that the import value is beginning to stagnate as of 2002. Analysis of sales amount reveals that domestic selling price for three development importer companies showing that after 1998, the prices of almost all items were falling dramatically. Regarding cost, analysis clarified that cost was falling for almost all items from the growth phase to the period of maturity assumed in this paper. These results show that the frozen-vegetable import market in Japan has reached the period of maturity.

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The purposes of this study were 1) to examine whether Andrich's binominal model in which a single skill is measured by repeated trials is applicable to athletic skill tests, and 2) to develop a simple and practical evaluation method using it. This approach was applied to a basketball shot skill test. The test subjects were 203 male college students, who performed ten different basketball shots from various distances and directions. They attempted each shot five times, and the number of successful shots was recorded. In addition, the number of shots and goals for each student was recorded, and their basketball experience was surveyed. From the results, the following findings were obtained.
1) Regarding the one-trial per one-item approach, no one-dimensionality was found and the discriminative power was low, and therefore this approach was considered to be valid. In the approach using the number of successful trials, one-dimensionality, and a high correlation between the number of successful trials for each item and the total number of successful trials were found. This indicated that this approach has higher validity.
2) Concerning difficulty, it was found that a shot from under the goal post was easiest, followed by a running shot and a free throw, in decreasing order of easiness. A three-point shot was the most difficult.
3) The correlation between item parameters obtained from two-divided specimens was high, and sample cross-validation was confirmed although the correlation of ability estimates, θ, was low between the items divided into two. However, this does not necessarily conflict with the cross-validation of ability estimates because the number of items was too small to be divided.
4) Judging from the value of the information function, accurate measurement equivalent to 0.9 reliability was possible when the value of θ was between 0.0 and 2.5. That is to say, it is considered that the skill test is valid as a means of discriminating ability among subjects with average to above-average ability, like those used in the present study.
5) The value of ability estimates, θ, was significantly correlated with the number of shots and goals during the skill test, as well as the basketball experience of the students during their period at junior high school and high school. It is considered that the value is valid as a representation of the subjects' basketball shooting skills.
Finally, this study proposed an evaluation sheet, taking advantage of the fact that the number of successful trials can be a sufficient statistic of θ. This sheet will make it possible to hypothesize ability estimates easily and link the value to an anticipated number of successful trials. In this study, two cases were evaluated using the sheet.

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The 3x3 basketball game is a relatively new sport with scarce information. This study aimed to differentiate the shooting situations of the 3x3 and 5-on-5 basketball games in elementary school and clarify the characteristics of the 3x3 game regarding the movement before the shot, shooting method and position. The merits of using the 3x3 game as a training tool for the 5-on-5 game and the points to keep in mind at that time were also examined.

The participants were 20 healthy male elementary school students (age: 11.2±0.6 years, height: 146.5±7.6 cm, weight: 35.9±5.8 kg, competition history: 3.4±1.3 years) who belonged to mini-basketball clubs and practiced five days in a week. In the 3x3 basketball games, eight 6-minute games were played with rest periods in between. On the other hand, five 6-minute games were played in the 5-on-5 basketball games, also with rest periods in between.

The results of this study were as follows: the 3x3 basketball game was characterized by more shots from outside the paint area in the “1-on-1” and “outside-catch-shot” scenarios. In the movement before the shot, there were many “outside play,” “ball clearing, check ball, ball carrying,” and “dribble drift” in the 3x3 games.

The 3x3 basketball game may be a good training tool for children in Japan in the developing age groups who play the game, owing to its demand for 1-on-1 play and outside shot development. However, with the current rules of the game, the possibility of a single player monopolizing the ball cannot be ruled out; therefore, some modifications to the rules are necessary.

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The purpose of this paper is to clarify deficiencies in existing research on the frozen vegetable export enterprise market in China. This paper presents an analysis from the viewpoint of the theory of industrial organization, clarifying the following points. First, because previous research has concentrated on a specific field in early research, a view of the entire structure of the industry is lost. Due to this, neither policy proposals nor the policy assessments have been have been undertaken as of yet. Second, there has been little research undertaken regarding industry channel leaders. The research concludes that the researcher and the research consortium should increase information exchange and discussion in a manner toward addressing these research deficiencies in the future.

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 This research aimed to clarify the significance of studying tactical conduct among basketball players from a semantic point of view. Based on the results of semantic analysis of tactical actions, we classified tactical ability as “the ability to grasp structure” and “the ability to grasp scenes,” and discussed the significance of this classification. The following were determined.

1) Better athletes do not memorize how to move in a one-on-one relationship, but instead the situation and action are united in meaning (symbolizing ability as functioning), resulting in tactical power. Player tactics must be analyzed from a semantic point of view.

2) In drill guidance aiming at establishing tactical patterns at the coaching site, it is insufficient to define tactical ability as the ability of the player to symbolize, and, by means of semantic analysis, to determine whether or not tactical action is possible. The presence of a coach who can discern this factor is indispensable.

3) Research targeting conventional tactical ability was examined by focusing on “the structure” aspects. It is thought that the significance of classifying basketball players' tactical abilities in this thesis can provide fundamental knowledge contributing to coaching of basketball by taking the ability to interpret “the scenes” as the subject of a survey.

4) The ability to grasp “the structure” and “the scene” is an essential element of tactical power, and is indispensable for proper play. The former is the ability to grasp feasibility and the latter is the ability to grasp the the momentum of the game.

5) By classifying the tactical power into the two abilities, the ability to grasp “the structure”, “the scenes”, we can define the point to evaluate and coach player’s tactical power.

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The purpose of this study was to focus on drives, which are an effective and important scoring method in basketball, and to identify the motion patterns associated with high success rates during actual games by analyzing the sequential motions of both offense and defense. The aim was to provide fundamental insights that could contribute to future coaching strategies. A total of 1,338 drive attempts initiated from ball reception in 156 games of the Kanto University Men’s Division 1 League were studied using decision tree analysis (CART). The results were revealed the following: (1) In baseline drives，when the defender raised their hand and adopted a stance with their middle-line-side foot forward (success rate: 65.3%), the offensive player achieved a high success rate (78.6%) by quickly pulling their non-pivot foot backward. Additionally，performing a small sweeping motion before dribbling was found to have the second-highest success rate (72.2%). (2) In middle-line drives, when the defender raised their hand and maintained a one-arm-length defensive distance (success rate: 73.3%), the offensive player achieved a high success rate (90.3%) by using a ball swing feint. Furthermore, a shot fake (success rate: 85.7%) and a jab step (success rate: 76.9%) were also found to be highly effective motions. These findings suggest that, for baseline drives, increasing the drive speed to avoid help defense is crucial, while for middle-line drives, eliciting defensive reactions is the key to successful execution.

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