2 RELATED WORK
Analysis related to sports have been widely studied,
among them, the application of the graph theory to
passes in a soccer game has been studied. When con-
ducting this research, data called passing distribution,
which records the number of passes as well as the
passer and receiver of the pass in a game, are often
publicly available.
In soccer, a pass that moves the ball to the oppo-
nent’s goal is considered to be an important offensive
move. Therefore, the analysis to create a graph net-
work based on passing distribution has been done by
other researchers. (Goncalves et al., 2017) conducted
a tactical analysis that considers the player’s position-
ings and the passes between players using passing dis-
tribution. They evaluated the performance of teams
participating in international youth games
1
and ar-
gued that players and tactical features are different
when comparing the two. (Cotta et al., 2013) ana-
lyzed the pass tactics of the Spanish national soccer
team of the 2010 FIFA World Cup. They investigated
the games from the quarter-finals to the final, taking
the transition of the number of passes and player’s po-
sitioning into account.
In addition, (Duch et al., 2010) measured central-
ity as a method to evaluate the players and the teams
in games by creating a graph network from passing
distribution. Furthermore, they modified between-
ness centrality used for the centrality measurement
and proposed flow centrality. This is a centrality mea-
surement using data on only the sequences of passes
leading to a shot. They measured flow centrality from
the passing-distribution data of EURO 2008. They
also evaluated each team by simply averaging play-
ers’ evaluations. From the results, they argued that
the team evaluation based on their method reflects the
game’s results better than one based on betweenness
centrality.
Indicators such as betweenness centrality and flow
centrality are used for centrality measurements. Flow
centrality is a method that measures centrality using
data on only the sequences of passes leading to a shot
and highly evaluates athletes who participated in the
scoring opportunity. However, if it is a small num-
ber of sequences in some games, flow centrality may
yields inaccurate measurements.
In this research, we propose a new model to alle-
viate this problem by improving flow centrality. We
also evaluate teams based on the model to show the
soundness of the model. Let us emphasize that pass-
ing distribution only records the number of passes
between players and cannot reproduce sequences of
1
The teams have players under 15 or 17 years of age.
Figure 1: Graph Network Example.
passes with three or more players. However, realiz-
ing the tendency of the sequence from a large number
of passes is possible. Therefore, we will apply and
verify this data in our research.
2.1 Betweenness Centrality
Centrality is an index of the degree of influence that
any node gives to other nodes in a graph network
(Tsugawa and Ohsaki, 2014). This index makes it
possible to estimate an important individual in an or-
ganization. Because soccer places more emphasis on
organizational team play, applying the index would be
appropriate.
Creating a graph network using nodes, edges, and
edge weights is a feasible endeavor. Figure 1 shows
an actual graph network example. When it is applied
to a soccer match, the node is the player, the edge is
the direction of the pass, and the weight of the edge is
the number of passes.
When this concept is applied to the graph theory, it
is possible to measure the centrality of the player node
by calculating how much the player node involved in
the sequence of a specific pass from the graph was
created by passing distribution. In soccer, there is a
consensus that the more passes a player is involved
in, the more contribution to a match she/he makes.
We accept this idea and conduct our study based on
it.
Betweenness centrality is calculated by counting
the number of times a node appears in one or more
shortest sequences of passes between nodes. The
weights of the sequence are the minimum value of the
edge weights. In the example of Figure 1, the shortest
sequence from node 7 to node 1 is 7 → 3 → 2 → 1,
7 → 4 → 2 → 1, 7 → 5 → 2 → 1, and 7 → 6 → 2 → 1.
The edge weights of 7 → 3 → 2 → 1, 7 → 5 → 2 → 1,
and 7 → 6 → 2 → 1 are one. In addition, 7 → 4 →
2 → 1 has the edge weights of three, and the number
of passes of the shortest sequence is three. Therefore,
the number of passes in the shortest sequence from
New Indicator for Centrality Measurements in Passing-network Analysis of Soccer
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