Analysis of dual sports performance typically involves observational techniques to gather data samples during actual competition. These techniques are limited by the amount of data that can be collected and the need to define the observable variables in advance. Today's advanced technologies have considerably overcome these limitations, enabling high‐volume data collection for post‐recording analysis. The present study was based on the three‐dimensional kinematic data recorded by the automated ball‐tracking Hawk‐Eye system between the 2003 and 2008 seasons in elite tennis tournaments, which provided a database of 262 596 points. The analysis consisted of an examination of the relationships between the various characteristics of the serve summed up by the resulting ball trajectory and winning‐point probabilities. The influence of factors such as serve speed, serve location, court surface, gender differences, and spin intensity on the winning‐point rate was assessed to gain insight into efficient serve tendencies in world‐class tennis. The implications for practitioners are highlighted and directions for future research in tennis performance analysis based on automatic ball tracking are proposed. © 2016 Wiley Periodicals, Inc. Statistical Analysis and Data Mining: The ASA Data Science Journal, 2016

The Senses Considered as Perceptual Systems (J. J. Gibson, 1966) remains a landmark achievement. In it, Gibson rejected major portions of classical theory on perception, offering in their place qualitatively new arguments. Yet, Gibson's rejection of classical assumptions was not complete. In this article, our focus is on relations between the senses. We argue that the 1966 book contains two different theories about relations between the senses. At some places in the book, Gibson advocated a view of intersensory relations that was similar to arguments offered by Aristotle. However, at other places in the book, Gibson offered a different interpretation, one that is incompatible with the Aristotelian view. We claim that these two views are incompatible, that is, we argue that Gibson made assertions that are mutually exclusive. We argue that Gibson's Aristotelian view should be rejected, and that it is incompatible with the concepts of specification and direct perception. In addition, we claim that, taken to its logical conclusion, Gibson's novel, non-Aristotelian argument mandates a broader, more general, more unitary and, ultimately, more successful view of perception, in which the senses operate as a single, irreducible, perceptual system.

Body movement influences the structure of multiple forms of ambient energy, including optics and gravito-inertial force. Some researchers have argued that egocentric distance is derived from inferential integration of visual and non-visual stimulation. We suggest that accurate information about egocentric distance exists in perceptual stimulation as higher-order patterns that extend across optics and inertia. We formalize a pattern that specifies the egocentric distance of a stationary object across higher-order relations between optics and inertia. This higher-order parameter is created by self-generated movement of the perceiver in inertial space relative to the illuminated environment. For this reason, we placed minimal restrictions on the exploratory movements of our participants. We asked whether humans can detect and use the information available in this higher-order pattern. Participants judged whether a virtual object was within reach. We manipulated relations between body movement and the ambient structure of optics and inertia. Judgments were precise and accurate when the higher-order optical-inertial parameter was available. When only optic flow was available, judgments were poor. Our results reveal that participants perceived egocentric distance from the higher-order, optical-inertial consequences of their own exploratory activity. Analysis of participants’ movement trajectories revealed that self-selected movements were complex, and tended to optimize availability of the optical-inertial pattern that specifies egocentric distance. We argue that accurate information about egocentric distance exists in higher-order patterns of ambient energy, that self-generated movement can generate these higher-order patterns, and that these patterns can be detected and used to support perception of egocentric distance that is precise and accurate.