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The Open Sports Sciences Journal, 2012, 5, 161-166
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Open Access
Representativeness of Offensive Scenarios to Evaluate PerceptualCognitive Expertise of Soccer Players
Filipe Casanova1,*, Júlio Garganta1 and José Oliveira2
1
Center of Research, Education, Innovation and Intervention in Sport (CIFI2D), Faculty of Sport, University of Porto,
FADEUP, Portugal
2
Research Center in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sport, University of Porto, FADEUP,
Portugal
3
Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
Abstract: In soccer, players have to carry out fast and accurate decisions in a complex and variable environment. The
purpose of the present study was to set representative attacking sequences trials for further use in the research of perceptual-cognitive skills for playing soccer. Elite Portuguese soccer coaches (n = 4, UEFA-A) were presented with separate
test film sequences encompassing structured attacking soccer actions to determine the representativeness of the scenarios.
In the experiment 41 offensive clips were viewed by the coaches. Each clip has approximately 5 s long with an inter-trial
interval of 5 s. To help the participants to the viewing process, just before the start of each clip a small circle surrounding
the ball it is shown on screen to indicate the area of its first appearance. The order of presentation of video clips was counterbalanced and randomly determined, during both moments of evaluation. In all testing film sequences watched the representativeness of an attacking soccer phase was significantly concordant among the observers (W = 1, p < 0.05). The reliability between observers was statistically consistent (! = 0.889). And the reproducibility of the results between both
moments of evaluation was very high (Z = 0; p = 1). The entire footage could be used in research that required knowing
the tactical awareness of soccer players.
Keywords: Attacking Game Patterns, Reliability, Soccer.
INTRODUCTION
The fastest and the most accurate decisions of a soccer
player elapses from information coming from several sources
(i.e., the ball, the other players) and the decision-making
process takes place under pressure with opponents trying to
restrict the “time” and “space” available. Considering the
specific constraints of training and competition demands, the
performer has to carry out several tasks, such as: (i) to extract from a scene the essential information needed to predict
future response requirements [1, 2]; (ii) to recall and recognize patterns of play properly [3, 4]; and (iii) to anticipate
successfully the opponent’s actions, based on advanced visual cues [5, 6]. It has been hypothesized that superior performance in sport is based on perceptual and cognitive skill
as well as the efficient and effective execution of movement
patterns. To differentiate the perceptual-cognitive skills
between participants, the researchers have used a range of
perceptual and cognitive measures that could be demonstrative of the high-ability during a dynamical sport task, such as
soccer [7].
*Address correspondence to this author at the Center of Research, Education, Innovation and Intervention in Sport (CIFI2D), Faculty of Sport, University of Porto, FADEUP, Portugal; Tel: +351912787206;
E-mail: fcasanova@fade.up.pt
1875-399X/12
Ericsson and Smith [8] proposed a descriptive and inductive framework for the study of expertise which they referred
to as the expert performance approach. Using this approach
they identified three researching stages. The first necessitates
that superior performance must be observed in situ and to
design representative tasks such that reliable individual differences in performance can be objectively measured under
laboratorial conditions. In the second stage the aim is to
determine the mechanisms underlying performance using
process-tracing measures such as eye-movement recordings,
verbal protocol analysis and/or representative task manipulations. The final stage involves efforts to detail the adaptive
learning and explicit acquisition processes relevant to the
development of expertise, with potential implications for
practice and instruction [9].
Williams et al. [7] have argued that perception and action
are mutually interdependent, cyclical processes that directly
constrain and influence one another. Although it has been
well documented that the effective use of relevant advance
visual cues facilitates sport performance by means of anticipating the intentions of the opponents [4, 7], the development of research protocols that provide relevant perception
and action are warranted, as well as the several paradigms
used to provide valuable insight into the effects that the decoupling of perception and action may have on performance
[7, 9, 10].
2012 Bentham Open
162 The Open Sports Sciences Journal, 2012, Volume 5
Instead of using field-based conditions, some researchers
have reported some limitations in using the video-based
paradigms to capture the appropriate essence of superior
performance [11]. However, when field-based approaches
are not possible, presentation of video images are appropriate
stimuli when compared to static slides. For example, Williams and Grant [12] have suggested a combination of subjective measures based on coach opinion and objective data
based on qualitative and quantitative video analysis. They
argued that in dynamic “open sports” the coaches’ opinions
could be gleaned pre- and post training using behavioral
assessment scales [13, 14], while their validity could be
substantiated using video analysis techniques [15]. Video
analysis has already been used to measure anticipation skill
in laboratory [16, 17] providing advantageously natural perception of the scene when compared with static slides [10].
Therefore, in the present study we aimed to create some
game setting scenarios that could be representative of a real
offensive soccer pattern. These situations were submitted to
a panel of elite soccer coaches.
METHODS
Participants
The representativeness of the scenarios was determined
through a panel of four elite Portuguese soccer coaches, with
UEFA-A license and not less than 10 years experience of
effective training. Participants were recruited and selected
from the National Association of Portuguese Soccer
Coaches’ database. The study was carried out under the
ethical guidelines of Faculty of Sport, University of Porto,
and participants provided consent before taking part in the
experiment.
Match Scenarios
Coaches were presented with separate video clips showing match sequences representing different game phases, i.e.,
attack, defense and transition play. The entire footage ends
with an offensive skill that could unbalance the defensive
organization. To guarantee that the scenario was truly realistic we conducted three practical sessions before the video
recording. The first and the second experiment sessions were
based on observing, memorizing and performing the theoretical schemes designed (for an example, see Fig. (1). The
third session could be defined as a brief summary of the last
two sessions. All the structured sequences were created by
the Soccer Unit of Faculty of Sport, University of Porto.
Portuguese Soccer players competing at the Second National
League (n = 22) participated in the scenarios build-up and
permission was obtained from each one of them for public
use of the recorded video images.
Each trial was filmed from the position behind (15m) and
slightly above (5m) the goal with a 16 by 9 video camera
(Sony DSR 570 DVCAM), such that the entire width of the
playing field could be viewed and ensuring that potentially
important information from wide positions was not eliminated. The elevated filming position helped give participants
some element of depth. A single frame from a typical structured action sequence is depicted in Fig. (2).
Casanova et al.
Fig. (1). Theoretical-scheme from the structured trial.
Fig. (2). Frame from the structured trial presented in video.
To edit the video into 41 different clips1 a Pinnacle Software package software, Avid Liquid edition 7, was used.
Each clip last approximately 5 s long with an inter-trial interval of 5 s. The test consists in a clip-by-clip analysis, and
just before the start of each clip, a small circle surrounding
the ball appeared on screen to indicate the area of its first
appearance. The clip stopped for 120 ms before the player in
possession of the ball was about to make a pass or take a shot
to goal or maintain the possession of the ball, and then the
clip projection continued until the final event was finished,
this last moment was identified when the screen turned to
black. These three potential events were classed as offensive
events: the Pass, i.e., a situation when the player has ball
possession and attempts to play it to his team-mate with any
part of the body except the head; the shot at goal, i.e., when
the player is in ball possession and makes an attempt to score
a goal for his team with any part of the body; the retain possession, i.e., when the player has ball possession and attempts to move with the ball, without losing it. All of the
playing sequences finished when an attack to the goal is
performed at the bottom of the screen.
Procedures
The video clips were presented in a dark room, in which
the coaches were seated 2m away from a Sony Television
(model LCD KDL40P3600E). To ensure that the action was
wholly perceived, the experts viewed the clips as many times
as they wanted. Coaches answer using pencil and specific
questionnaire. The panel of experts carried out another
evaluation within 2 months of the first test.
The criterion was based on a 5-point Likert-type scale,
where 5 means total agreement with the correct representativeness of the action, whereas 1 indicates total disagreement
(see Table 1). Questionnaires based on Likert scales are
often used in psychometrics, social studies and panels, in
marketing research [18, 19], or in perceptual-cognitive performance research [20]. The order of presentation of video
clips was counterbalanced and randomly determined, during
1
To have full access to the clips please send an email to fcasanova@fade.up.pt and/or jgargant@fade.up.pt
Representativeness of Offensive Scenarios to Evaluate Perceptual-Cognitive
Table 1.
Likert-Type Scale (5 Point)
Likert-type Scale
1
Totally Disagree
2
Disagree
3
Neither Disagree nor Agree
4
Agree
5
Totally Agree
both moments of evaluation. Four additional trials were
presented to participants prior to testing so that they could
familiarize themselves with the video test and protocol.
Statistical Analysis
Descriptive statistical analysis was used to examine the
valid values of the chosen Likert-point scale. To test the
agreement between observers we used the Kendall’s coefficient of concordance (W). Internal consistence reliability
between observers was tested by using the Cronbach’s Alpha
(!). To test the construct validity (re-test) of the scenarios
we used the nonparametric Wilcoxon Signed Rank Test (Z).
Statistical significance was set at p < 0.05 for all tests. The
statistical software used was the SPSS Version 18.0 (SPSS
Inc., Chicago, II).
RESULTS
The final offensive event of each clip is highlighted in
Table 2.
The valid values of the chosen Likert-point scale shows
that the entire sequence of the 41 clips projected was representative of a soccer game pattern, ending with an offensive
event (see Table 3). As an exception, the clip 41 was rated at
level 4 in the Likert-point Scale, since in the opinion of three
expert coaches (A, C and D) this clip could be ended with a
pass to another player.
In all test film sequences the representativeness of the
game scenarios observed was significantly concordant
among the observers (W = 1; p < 0.05). Moreover, the internal consistency reliability between observers showed that the
responses scored were statistically consistent (! = 0.889; p <
0.05).
Concerning the construct validity of the clips, the results
obtained illustrated that when the experts watched again the
projection of the 41 clips the values of the Likert-point scale
were strongly reproduced (Z = 0; p = 1).
DISCUSSION
The aim of the present study was to set representative
attacking sequences trials for further use in the research of
perceptual-cognitive skills for playing soccer. According to
the results of the present study the panel of expert coaches
agreed that the entire footage was representative of a real
soccer situation which ends with a correct offensive event.
Therefore, it seems useful tool to be used in perceptual-
The Open Sports Sciences Journal, 2012, Volume 5
163
cognitive research, namely under controlled laboratory tasks.
The design of the different game patterns used in this study
was developed according to the three main categories of
problems brought by team sports, which are: (i) space and
time, (ii) information, and (iii) organization [21]. So, we
have been constantly concerned with a tactical / strategic
purpose, during the prescription of the game patterns and the
practicing situations, as well.
Even the final event of the player in possession of the
ball was sustained in Hughes et al. [22] reports. They defined a perturbation in soccer as an incident that changes the
rhythmic flow of attacking and defending, leading to a shooting opportunity. For example, a perturbation could be identified from a penetrating pass, a dribble, a change of pace or
any skill that creates a disruption in the defense and allows
an attacker a shooting opportunity. In some cases, a perturbation of the defense may not result in a shot, owing to defensive skills or a lack of skill in attack. The clip stopped before
the player in ball possession was either doing pass, shot at
goal or retain possession. Both, pass and shot at goal have
been associated with teams that has a higher percentage of
success [23, 24] and the retain possession is being classified
as the main goal to reach the truly purpose of the game, to
score a goal. Bell-Walker et al. [24] reported that the successful teams at World Cup 2006, who were better able to
hold ball possession, created more attempts at goal from
open play and they also suggested that these teams had more
positive attacking attitude.
Regarding to the duration of a video clip, McRobert et al.
[25] noted that the perceptual and cognitive skills are inferred from the quality, speed and accuracy of an individual’s performance, with minimal attempt to explain the cognitive processes involved during anticipation. Another scientific finding was reported by Ericsson and Simon [26] as
they pointed out that subjects were able to recall accurately
and completely the sequence of thoughts, cognitive information, after a 0.5 – 10s task performance.
Although the video presentations reduce a threedimensional setting to a reality of two-dimensional scenarios, we tried to give to the subjects enough references of
depth and width by elevating the film recording position and
by using a 16 by 9 video camera, respectively. Another advantage of film projection is that it enables sequences of
action to be reproduced in a consistent manner from trial to
trial [27].
The results of the valid values of the Likert-point scale
demonstrated that the panel of experts agreed with the representativeness of the clips. An exception of last decision of
the player in ball possession was reported by three coaches
in the clip number 41, when the player did not pass the ball
to a team-mate in a better position/space to receive it (see
Table 2). Although being the game scenario included in clip
41 a common situation in soccer matches, the lower degree
of total agreement between experts regarding the appropriate
decision of the player in possession of the ball might preclude it’s utilization as a scenario for assessment perceptualcognitive skill, since it could influence components such as
advanced visual cue utilization, pattern recall and recogni
tion, visual search behaviour and the knowledge of
164 The Open Sports Sciences Journal, 2012, Volume 5
Table 2.
Casanova et al.
Offensive Event in Each Clip
Event
Clip
Pass (To Which Player)
1
X (Right Winger)
2
X (Left Winger)
3
X (Center Midfielder)
Shot at Goal
4
5
Retain Possession
X
X (Center Midfielder)
6
X
7
X
8
X (Left Winger)
9
X (Striker)
10
11
X
X (Striker)
12
X
13
X
14
X (Left Midfielder)
15
X (Striker)
16
X (Left Midfielder)
17
X
18
X
19
X
20
X
21
X (Left Winger)
22
X (Right Midfielder)
23
24
X
X (Left Midfielder)
25
26
X
X (Left Midfielder)
27
X
28
X
29
X (Center Midfielder)
30
X
31
X (Right Winger)
32
X (Striker)
33
X (Center Midfielder)
34
35
X
X (Left Winger)
Representativeness of Offensive Scenarios to Evaluate Perceptual-Cognitive
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165
Table 2. Contd.....
Event
Clip
Pass (To Which Player)
Table 3.
36
X (Left Winger)
37
X (Right Midfielder)
38
X (Striker)
39
X (Left Winger)
40
X (Right Winger)
41
X (Left Back)
Shot at Goal
Retain Possession
Mean Valid Values of the Likert-point Scale (± SD) Pointed out by the Coaches, in Both Moments of Evaluation
Coach
Test
Re-Test
A
4.98 ± 0.16
4.98 ± 0.16
B
5±0
5±0
C
4.98 ± 0.16
4.98 ± 0.16
D
4.98 ± 0.16
4.98 ± 0.16
situational probabilities. In addition, previous published
investigations support the use of this type of instrument to
assess perceptual-cognitive performance [7, 10, 28-31].
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The authors confirm that this article content has no conflicts of interest.
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