Duarte Araujo | Universidade de Lisboa (original) (raw)

Papers by Duarte Araujo

Journal of Expertise, 2021

This paper considers the study of driving skill and performance of human drivers as a key domain ... more This paper considers the study of driving skill and performance of human drivers as a key domain to improve the design and the “expertise” of self-driving cars. Concerted driving with others in roundabouts is a special kind of social expertise —understood as competence in ordinary, mundane activities— deployed by members of society. We illustrate our theoretical arguments about how human cognition works in driving contexts with the analysis of three paradigmatic examples through the lenses of the ecological framework. Based on these analyses, we discuss the need for a more robust and realist theory for developing self-driving cars as potential complications arising from interactions between human drivers and self-driving cars cannot be solved with current socio-cognitive models for decision-making and social coordination. The ecological framework considers that drivers’ exploratory activities rely on the utilization of affordances, rather than on the internal processing of information, which is currently the default assumption guiding self-driving car design. The ecological approach assumes that drivers are embedded agents that act within increasingly complex technological envelopes. Such a framework could be used to investigate how digital driving landscapes may be closely tailored to the drivers’ activities. Finally, future research on driving design should investigate how affordances can be matched with emerging digital technologies for reducing accidents and improving traffic flow.

Sports Medicine, 2013

Previous research has proposed that team coordination is based on shared knowledge of the perform... more Previous research has proposed that team coordination is based on shared knowledge of the performance context, responsible for linking teammates' mental representations for collective, internalized action solutions. However, this representational approach raises many questions including: how do individual schemata of team members become reformulated together? How much time does it take for this collective cognitive process to occur? How do different cues perceived by different individuals sustain a general shared mental representation? This representational approach is challenged by an ecological dynamics perspective of shared knowledge in team coordination. We argue that the traditional shared knowledge assumption is predicated on 'knowledge about' the environment, which can be used to share knowledge and influence intentions of others prior to competition. Rather, during competitive performance, the control of action by perceiving surrounding informational constraints is expressed in 'knowledge of' the environment. This crucial distinction emphasizes perception of shared affordances (for others and of others) as the main communication channel between team members during team coordination tasks. From this perspective, the emergence of coordinated behaviours in sports teams is based on the formation of interpersonal synergies between players resulting from collective actions predicated on shared affordances.

PloS one, 2014

Similar to other complex systems in nature (e.g., a hunting pack, flocks of birds), sports teams ... more Similar to other complex systems in nature (e.g., a hunting pack, flocks of birds), sports teams have been modeled as social neurobiological systems in which interpersonal coordination tendencies of agents underpin team swarming behaviors. Swarming is seen as the result of agent co-adaptation to ecological constraints of performance environments by collectively perceiving specific possibilities for action (affordances for self and shared affordances). A major principle of invasion team sports assumed to promote effective performance is to outnumber the opposition (creation of numerical overloads) during different performance phases (attack and defense) in spatial regions adjacent to the ball. Such performance principles are assimilated by system agents through manipulation of numerical relations between teams during training in order to create artificially asymmetrical performance contexts to simulate overloaded and underloaded situations. Here we evaluated effects of different nume...

Human Movement Science, Jan 1, 2011

Here, we report an investigation of the patterned movement behavior of players for a specific sub... more Here, we report an investigation of the patterned movement
behavior of players for a specific sub-phase of the game of futsal,
namely when the goalkeeper for the attacking team is substituted
with an extra outfield player. The movement trajectories of the ball
and players were recorded in both lateral and longitudinal direc-
tions and investigated using relative phase analysis. Some differ-
ences in phase relations between different playing dyads were
noted, indicating specificity of phase attractions, or otherwise, for
certain players. In general terms, the defenders demonstrated
strong in-phase attractions with the ball and with each other,
whereas weaker phase attractions, indicated by increased relative
phase variability, were observed for the attackers and ball, as well
as between attackers themselves. These results demonstrate differ-
ent coordination dynamics for the defending and attacking dyads,
from which we interpret evidence for different playing sub-sys-
tems consistent with different team objectives linked together in
an overarching game structure. In keeping with dynamical systems
theory for complex systems, we view this sub-phase of futsal as
being characterized by coordinated behavior patterns that emerge
as a result of self-organizing processes. These dynamic patterns are
generated within functional constraints, with players and teams
exerting mutual influence on each other.

Human Movement Science, 2015

journal hom ep ag e: www.elsevier.com/loc ate/humov have been constrained by the angular relation... more journal hom ep ag e: www.elsevier.com/loc ate/humov have been constrained by the angular relations sustained between participants relative to the scoring target. Results revealed the functionality of exploratory behaviors of participants attempting re-align spatial relations with an opponent in 1v1 sub-phases of team games.

Perceptual and motor skills, Jan 1, 2010

In 2009, Kannekens and colleagues evaluated the development of tactical skills of elite youth foo... more In 2009, Kannekens and colleagues evaluated the development of tactical skills of elite youth football players using a method based on verbal reports. Results showed no improvements in players’ tactical skills over the years of their longitudinal study. These results are based on an erroneous assumption that tactical skills and verbalizations about tactical skills are equivalent. This note comprises an explanation of why verbal reports are not a valid measure of tactical skills.

The Open Sports …, Jan 1, 2010

The main goal of performance analysis in team sports has been the identification of data frequenc... more The main goal of performance analysis in team sports has been the identification of data frequencies or sequences of actions in a temporal line, based on the assemblage of numerous discrete variables. This focus may be
deemed as not displaying the foremost team sport feature, i.e., the dynamics of the interaction between two teams. In order to better understand the dynamic patterns of the game, the methods commonly applied must be furthered in a functional perspective. Underpinned in the Ecological Dynamics approach to decision making in sport, this paper regards performance analysis as a process of synthesis and parsimonious explanation of game’s functional nature. Accordingly, we argue the importance of the following three aspects: i) game must be viewed considering different levels of analysis;
ii) there is a functional role of variability in players’ behaviour that must be included in the analysis; iii) human behaviour is better understood if we consider how the dynamics reflects individual and collective perceptual-action couplings.

This paper analyzes effects of different practice task constraints on heart rate (HR) variability... more This paper analyzes effects of different practice task constraints on heart rate (HR) variability during 4v4 smallsided football games. Participants were sixteen football players divided into two age groups (U13, Mean age: 12.4±0.5 yrs; U15: 14.6±0.5). The task consisted of a 4v4 sub-phase without goalkeepers, on a 25x15 m field, of 15 minutes duration with an active recovery period of 6 minutes between each condition. We recorded players' heart rates using heart rate monitors (Polar Team System, Polar Electro, Kempele, Finland) as scoring mode was manipulated (line goal: scoring by dribbling past an extended line; double goal: scoring in either of two lateral goals; and central goal: scoring only in one goal). Subsequently, %HR reserve was calculated with the Karvonen formula. We performed a time-series analysis of HR for each individual in each condition. Mean data for intra-participant variability showed that autocorrelation function was associated with more short-range dependence processes in the "line goal" condition, compared to other conditions, demonstrating that the "line goal" constraint induced more randomness in HR response. Relative to inter-individual variability, line goal constraints demonstrated lower %CV and %RMSD (U13: 9% and 19%; U15: 10% and 19%) compared with double goal (U13: 12% and 21%; U15: 12% and 21%) and central goal (U13: 14% and 24%; U15: 13% and 24%) task constraints, respectively. Results suggested that line goal constraints imposed more randomness on cardiovascular stimulation of each individual and lower inter-individual variability than double goal and central goal constraints.

Background and objective. In the last years, several motion analysis methods have been developed ... more Background and objective. In the last years, several motion analysis methods have been developed without considering representative contexts for sports performance. The purpose of this paper was to explain and underscore a straightforward method to measure human behavior in these contexts.
Material and methods. Procedures combining manual video tracking (with TACTO device) and bidimensional reconstruction (through direct linear transformation) using a single camera were used in order to capture kinematic data required to compute collective variable(s) and control parameter(s).
These procedures were applied to a 1vs1 association football task as an illustrative subphase of team sports and will be presented in a tutorial fashion.
Results. Preliminary analysis of distance and velocity data identified a collective variable (difference between the distance of the attacker and the defender to a target defensive area) and two nested control parameters (interpersonal distance and relative velocity).
Conclusions. Findings demonstrated that the complementary use of TACTO software and direct linear transformation permit to capture and reconstruct complex human actions in their context in a low dimensional space (information reduction)

Objectives: This study aimed to explain how defenders intercept the trajectory of a passing ball ... more Objectives: This study aimed to explain how defenders intercept the trajectory of a passing ball by understanding how they coupled their actions to critical information sources in a competitive performance
setting in team sports.
Design: Time series data on movement displacements of fifteen senior male futsal performers were recorded and digitized during nine competitive futsal games.
Method: Performance was recorded by a digital camera and digitized with TACTO software. The spatial etemporal dynamics of performers during ten intercepted and ten non-intercepted passes were compared. Time to ball interception was calculated by the difference between the time of each defender to an interception point in ball trajectory and the time of the ball’s arrival at the same interception point.
Initial distances between defenders and ball and velocity data of defenders and ball over time were also recorded.
Results: Time to ball interception revealed positive values when passes were not intercepted, and negative to zero values when passes were intercepted. At the moment of pass initiation defenders’
distances to the ball constrained their possibilities for successful interception. Analysis of defenders’ adaptations to the environment revealed that continuous changes in the defenders’ velocities constrained their success of the interception.
Conclusions: Intercepted passes seemed to be influenced by the continuous regulation of a defender’s velocity relative to the ball’s trajectory. Time to ball interception is a variable that captured the emergent functional behaviours of players attempting to intercept the trajectory of a pass in the team sport of
futsal.

This study examined the effects of manipulating relative positioning between defenders (initial d... more This study examined the effects of manipulating relative positioning between defenders (initial distance apart) on emergent decision-making
and actions in a 1 vs. 2 rugby union performance sub-phase. Twelve experienced youth players performed 80 trials of a 1 (attacker) vs. 2
(defenders) practice task in which the starting distance between defenders was systematically decreased. Movement displacement trajectories
of participants were video recorded to obtain 2D positional data. The independent variable was the starting distance between defenders and
dependent variables were: (i) performance outcome (try or tackle), (ii) mean speed of all players during performance, and (iii) time between
the first crossover and the end of the trial. Repeated measures ANOVA was used to compare the effects of different starting distances on
performance. Shorter starting distances between defenders were associated with a higher frequency of effective tackle outcomes, lower mean
speeds of all participants, and a greater time period between the first crossover and the end of the trial. Decision-making behaviours emerged
as a function of changes in participants’ spatial location during performance. This observation supports the importance of manipulating key
spatial-temporal variables in designing representative practice task constraints that induce functional player–environment interactions in team
sports training.

Previous research on coordination dynamics of 1 vs. 1 sub-phases in team sports has reported stab... more Previous research on coordination dynamics of 1 vs. 1 sub-phases in team sports has reported stable emergent patterns of coordination in the displacement trajectories of attackers and defenders. The aim of this study was to use attacker–defender interactions in competitive team match-play to investigate how the locations of the goal and ball constrain the pattern-forming dynamics of attacker–defender dyadic systems. Ten high-level futsal matches were filmed and 13 goal sequences selected for analysis. Displacements of the players and the ball were filmed and digitized from 52 attacker–defender dyadic system interactions. Results showed that, although attackers and defenders exhibited similar angular orientations to the goal, the latter always remained closer to the goal than attackers. Observations revealed that in-phase patterns of coordination emerged from changes to both the distances and angles of attackers and defenders to the goal. Attackers always remained closer to the ball than defenders, while the latter exhibited a lower angle to the ball than attackers. A pattern of in-phase coordination modes emerged between the attackers and defenders' distances and angles to the ball. This study helps us to understand interpersonal interactions in team sports by explaining how attackers and defenders use information about their relative positioning to the goal and the ball to perform successfully.

Neste estudo tivemos como objectivo investigar se o processo decisional surge através de um proce... more Neste estudo tivemos como objectivo investigar se o processo decisional surge através de um processo relacional “on-line” entre indivíduos e ambiente para a concretização de um objectivo. Para tal, utilizámos 35 situações de passe numa tarefa de Futsal onde avaliámos como evolui o contexto decisional até ao momento do passe. Neste estudo utilizámos como variáveis as distâncias interpessoais entre jogadores, as suas velocidades instantâneas e a fase relativa entre as referidas distâncias. Como resultados, verificámos que entre o momento de recepção da bola até à realização do passe, existe uma convergência nas distâncias entre os jogadores para um valor estável e uma divergência das suas velocidades. Estes resultados sugerem que a decisão para passar emerge face à afinação perceptual do indivíduo com bola à informação relevante do ambiente. Esta afinação permite a exploração e detecção de affordances, para passar a bola, definidas por uma janela espácio-temporal entre os jogadores.

Correspondência para: Bruno Travassos, brunotravassos@hotmail.com; Tel: 275320690 Os desportos co... more Correspondência para: Bruno Travassos, brunotravassos@hotmail.com; Tel: 275320690 Os desportos colectivos caracterizam-se pelas relações estabelecidas entre os jogadores, quer de colaboração, quer de oposição, num dado contexto (p.ex., jogo oficial de uma dada liga) para atingir um determinado fim (p.ex., marcar golo). Nesta perspectiva são fundamentais comportamentos de diálogo que permitam desenvolver a dinâmica entre os jogadores da mesma equipa, sob a oposição do adversário. Nesta relação de forças, torna-se fundamental um equilíbrio entre as funções a desempenhar por cada jogador, inseridas numa organização colectiva, e a capacidade que cada um tem em explorar o contexto de jogo. A exploração do contexto de jogo tem grande variabilidade, mas não é aleatória, pois visa a obtenção do objectivo da equipa para o jogo. Neste sentido, atingir o objectivo da equipa, implica criatividade nas acções do jogo, de modo a desequilibrar o adversário, mesmo durante os processos defensivos.

La reciente aplicación de las teorías de la complejidad a la actividad física nos obliga a recons... more La reciente aplicación de las teorías de la complejidad a la actividad física nos obliga a reconsiderar los métodos que a menudo se utilizan en los procesos de enseñanza-aprendizaje en la educación física. En este artículo, se presenta un ejemplo de aplicación concreta al fútbol, considerando que los procesos relacionados con la toma de decisiones que se producen son fruto de la auto-organización del alumnado con el contexto en
el cual se produce la práctica. En lugar de pretender estabilizar comportamientos, mediante la comúnmente denominada automatización, se buscará un método más acorde con el objetivo real del juego, que será justamente la desestabilización de los comportamientos del oponente.
El alumnado necesitará explorar el contexto e interactuar con él para resolver lo que demanda cada situación única. Para ello, se propone una progresión en tres fases con ejemplos de tareas concretas. En la primera, se explorarán las posibilidades de juego, creando situaciones representativas que permitan una gran variedad de comportamientos para conseguir el objetivo. En la segunda, se pretenderá la adaptación de las acciones a la información que se recibe. Por último, en la tercera, se maximizarán todas las posibilidades para conseguir un determinado objetivo.

This study investigated the influence of interpersonal coordination tendencies on performance out... more This study investigated the influence of interpersonal coordination tendencies on performance outcomes of 1-vs-1 sub-phases in youth soccer. Eight male developing soccer players (11.8±0.4 yrs; training experience: 3.6±1.1 yrs) performed an in situ simulation of 1-vs-1 sub-phase of soccer. Data from 82 trials were obtained with motion-analysis techniques, and relative phase used to measure the space-time coordination tendencies of attacker-defender dyads. Approximate entropy (ApEn) was then used to quantify the unpredictability of interpersonal interactions over trials. Results revealed how different modes of interpersonal coordination emerging from attacker-defender dyads influenced the 1-vs-1 performance outcomes. High levels of space-time synchronisation (47%) and unpredictability in interpersonal coordination processes (ApEn: 0.91±0.34) were identified as key features of an attacking player’s success. A lead-lag relation attributed to a defending player (34% in -30º bin) and a more predictable coordination mode (ApEn: 0.65±0.27, p < .001), demonstrated the coordination tendencies underlying the success of defending players in 1-vs-1 sub-phases. These findings revealed how the mutual influence of each player on the behaviour of dyadic systems shaped emergent performance outcomes.

In this study, we examined the effects of relative positioning of attacker-defender dyads to the ... more In this study, we examined the effects of relative positioning of attacker-defender dyads to the basket on interpersonal coordination tendencies in basketball. To achieve this aim, four right-hand dominant basketball players performed in a 1 vs. 1 sub-phase, at nine different playing locations relative to the basket (from 0° to 180°, in 20° increments). Performers' movement displacement trajectories were video-recorded and digitized in 162 trials. Results showed that interpersonal coordination tendencies changed according to the scaling of the relative position of performers to the basket. Stable in-phase modes of coordination were observed between performers' longitudinal and lateral displacements (50.47% and 43.02%) on the left side of the court. On the right side of the court, a shift in the dominant mode of coordination was observed to a defender lead-lag of -30°, both for longitudinal and lateral displacements (30.51% and 32.65%). These results suggest how information about dribbler hand dominance and relative position to the basket may have constrained attacker-defender coordination tendencies in 1 vs. 1 sub-phases of basketball.

This study investigated effects of manipulating the number of action possibilities in a futsal pa... more This study investigated effects of manipulating the number of action possibilities in a futsal passing task to understand the representativeness of practice tasks designs. Eight male senior futsal players performed a passing task in which uncertainty on passing direction for the player in possession of the ball was increased in four conditions and compared with passing data from a competitive match. Performance during a passing task and competitive futsal performance was compared using ball speed and passing accuracy data. Ball speed data were analysed by approximate entropy (ApEn) to capture their regularity in each of the four conditions and during competitive performance. Significantly high levels of regularity were observed in predetermined passes in comparison with emergent passes (i.e., passes with high number of possibilities for action). Similar results for ball speed regularity were observed between practice tasks with a high number of possibilities for action (i.e., emergent passes) and competitive performance. Similar results were observed for passing accuracy in practice tasks with a high number of possibilities for action compared to competitive performance. Increases in the number of action possibilities during practice improved action fidelity of tasks in relation to competitive performance.

Complex environments require effective individual/team decision making and adaptation to environm... more Complex environments require effective individual/team decision making and adaptation to environmental changes. Salas et al. (2007) consider that this process implies the development of Team Cognition. The aim of this presentation is to advocate
an Eco-Dynamic approach for developing decision making in teams. Following this approach we considered team behaviour as an emergent process brought by the interaction between the individuals, environmental and task constraints rather than being controlled by individual minds. This means that team cognition should be developed as the capacity of different players to become perceptually attuned to the relevant information of the environment. Relevant means that this information specifies goal achievement. To illustrate our perspective we present an example for training the development of emergent team decision making processes.

Research on 1vs1 sub-phases in team sports has shown how one player coordinates his/her actions w... more Research on 1vs1 sub-phases in team sports has shown how one player coordinates his/her actions with his/her opponent and the location of a target/goal to attain performance objectives. In this study, we extended this approach to analysis of 5vs5 competitive performance in the team sport of futsal to provide a performance analysis framework that explains how players coordinate their actions to create/prevent opportunities to score goals. For this purpose, we recorded all 10 futsal matches of the 2009 Lusophony Games held in Lisbon. We analysed the displacement trajectories of a shooting attacker and marking defender in plays ending in a goal, a goalkeeper's save, and a defender's interception, at four specific moments during performance: (1) assisting attacker's ball reception and (2) moment of passing, (3) shooter's ball reception, and (4), shot on goal. Statistical analysis showed that when a goal was scored, the defender's angle to the goal and to the attacker tended to decrease, the attacker was able to move to the same distance to the goal alongside the defender, and the attacker was closer to the defender and moving at the same velocity (at least) as the defender. This study identified emergent patterns of coordination between attackers and defenders under key competitive task constraints, such as the location of the goal, which supported successful performance in futsal.

Journal of Expertise, 2021

Sports Medicine, 2013

PloS one, 2014

Human Movement Science, Jan 1, 2011

Human Movement Science, 2015

Perceptual and motor skills, Jan 1, 2010

The Open Sports …, Jan 1, 2010

The combination of sports sciences theorization and social networks analysis (SNA) has offered us... more The combination of sports sciences theorization and social networks analysis (SNA) has offered useful new insights for addressing team behavior. However, SNA typically represents the dynamics of team behavior during a match in dyadic interactions and in a single cumulative snapshot. This study aims to overcome these limitations by using hypernetworks to describe illustrative cases of team behavior dynamics at various other levels of analyses. Hypernetworks simultaneously access cooperative and competitive interactions between teammates and opponents across space and time during a match. Moreover, hypernetworks are not limited to dyadic relations, which are typically represented by edges in other types of networks. In a hypernetwork, n-ary relations (with n > 2) and their properties are represented with hyperedges connecting more than two players simultaneously (the so-called simplex-plural, simplices). Simplices can capture the interactions of sets of players that may include an arbitrary number of teammates and opponents. In this qualitative study, we first used the mathematical formalisms of hypernetworks to represent a multilevel team behavior dynamics, including micro (interactions between players), meso (dynamics of a given critical event, e.g., an attack interaction), and macro (interactions between sets of players) levels. Second, we investigated different features that could potentially explain the occurrence of critical events, such as, aggregation or disaggregation of simplices relative to goal proximity. Finally, we applied hypernetworks analysis to soccer games from the English premier league (season 2010-2011) by using two-dimensional player displacement coordinates obtained with a multiple-camera match analysis system provided by STATS (formerly Prozone). Our results show that (i) at micro level the most frequently occurring simplices configuration is 1vs.1 (one attacker vs. one defender); (ii) at meso level, the dynamics of simplices transformations near the goal depends on significant changes in the players' speed and direction; (iii) at macro level, simplices are connected to one another, forming "simplices of simplices" including the goalkeeper and the goal. These results validate qualitatively that hypernetworks and related compound variables can capture and be used in the analysis of the cooperative and competitive interactions between players and sets of players in soccer matches.