title: The geometry of expertise.
abstract: Theories of expertise based on the acquisition of chunk and templates suggest a differential geometric organization of perception between experts and novices. It is implied that expert representation is less anchored by spatial (Euclidean) proximity and may instead be dictated by the intrinsic relation in the structure and grammar of the specific domain of expertise. Here we set out to examine this hypothesis. We used the domain of chess which has been widely used as a tool to study human expertise. We reasoned that the movement of an opponent piece to a specific square constitutes an external cue and the reaction of the player to this "perturbation" should reveal his internal representation of proximity. We hypothesized that novice players will tend to respond by moving a piece in closer squares than experts. Similarly, but now in terms of object representations, we hypothesized weak players will more likely focus on a specific piece and hence produce sequence of actions repeating movements of the same piece. We capitalized on a large corpus of data obtained from internet chess servers. Results showed that, relative to experts, weaker players tend to (1) produce consecutive moves in proximal board locations, (2) move more often the same piece and (3) reduce the number of remaining pieces more rapidly, most likely to decrease cognitive load and mental effort. These three principles might reflect the effect of expertise on human actions in complex setups.
authors.affiliation: Laboratorio de Neurociencia Integrativa, Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires Buenos Aires, Argentina ; IFIBA, CONICET Buenos Aires, Argentina.
authors.forename: María J
authors.initials: MJ
authors.lastname: Leone
authors.affiliation: Departamento de Computación, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires Buenos Aires, Argentina.
authors.forename: Diego
authors.initials: D
authors.lastname: Fernandez Slezak
authors.affiliation: Computational Biology Center, T.J. Watson Research Center, International Business Machines Yorktown Heights, NY, USA.
authors.forename: Guillermo A
authors.initials: GA
authors.lastname: Cecchi
authors.affiliation: Laboratorio de Neurociencia Integrativa, Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires Buenos Aires, Argentina ; IFIBA, CONICET Buenos Aires, Argentina ; Universidad Torcuato Di Tella Buenos Aires, Argentina.
authors.forename: Mariano
authors.initials: M
authors.lastname: Sigman
keywords: attentional control; chess expertise; chunks; object representation; spatial proximity