Francesco Martino

Improving social game engagement on facebook through enhanced socio-contextual information

In this paper we describe the results of a controlled study of a social game, Magpies, which was built on the Facebook Online Social Network (OSN) and enhanced with contextual social information in the form of a variety of social network indices. Through comparison with a concurrent control trial using an identical game without the enhanced social information, it was shown that the additional contextual data increased the frequency of social activity between players engaged in the game. Despite this increase in activity, there was little increase in growth of the player-base when compared to the control condition. These findings corroborate previous work that showed how socio-contextual enhancement can increase performance on task-driven games, whilst also suggesting that it can increase activity and engagement when provided as context for non task-driven game environments.

Eldergames project: An innovative mixed reality table-top solution to preserve cognitive functions in elderly people

Advances in new technologies can provide solutions to prevent impairments associated with normal aging, track performance at specific tasks, and provide an entertaining experience to elderly people. Based on these premises we present Eldergames, an EU funded project that aims at creating an interactive tool for preserving cognitive functions impaired by aging and affording sociability. A first prototype has recently been created and its acceptance has been tested on groups of elderly users. The prototype proved able to provide a pleasant social cognitive training because of its simplicity, usability of the interface, and multiplayer architecture.

Presence in the age of social networks: augmenting mediated environments with feedback on group activity

The present study aimed at increasing behavioral engagement in groups of networked people by providing feedback on the group activity. Each participant logged into an on-line virtual environment for four subsequent treasure-hunting sessions along with other nine players. During the game, all players communicated dyadically through textual chats, and searched for the treasures in the virtual environment. In two conditions, the participants received a visual feedback depicting the communication activity with the group based on social network analysis indices (i.e. ‘centrality’ or ‘reciprocity’). Feedback was not provided in the third condition. The underlying assumption was that if the group activity becomes more visible to the individual user through the feedback, then the behavioral engagement with the group increases. The resulting behavioral engagement was measured with two techniques, one based on the amount of messages exchanged and one based on self-reported measures. The results show that feedback improved the exchange of messages with respect to the control condition and that this effect was only partially captured by self-reported measures.

Unveiling the structure: effects of social feedback on communication activity in online multiplayer videogames

Feedback intervention in computer-mediated situations can be interpreted as a way to augment communication. According to this idea, this study investigates the effect of providing a group with a Social Network Analysis-based feedback on communication in an on-line game where players talk to each other via textual chat. Three different situations across two different sessions were compared: an Informed Group with a correct feedback, a not-Informed Group with no feedback and a mis-Informed group with an incorrect feedback. Results show that giving correct information increases the related dimensions of communication, while the absence of feedback and the incorrect feedback were not accompanied by any significant modification.

Super-feet: a wireless hand-free navigation system for virtual environments

Navigation is a fundamental task in virtual environments. Some of the metaphors that are used to determine where users want to be placed at each moment are based on physical locomotion. Usually, these techniques require the use of several sensors and complex algorithms. In this paper, we present Super-Feet, a wireless navigation system controlled by natural movements without requiring invasive methods or devices. It uses a low-cost infra-red system to detect the instantaneous position of both feet and this information is translated into a walking and rotation velocity in the environment. Preliminary results show that Super-Feet navigation is more accurate but slower than joypad based navigation systems.

Shared virtual environment (SVE): a framework for developing social games

The communication channels are changing. More and more, face to face communication is being replaced by computer mediated communication. Using mediated communication, the non-verbal communication cues that are available in face to face communication are not. PASION is a European project where mediated communication is augmented. In this paper we present the Shared Virtual Environment (SVE), the framework to be used for the development of two types of applications (social gaming and collaborative work) where augmentation will be studied. The first version of SVE has been used for the development of the first version of a pervasive game for treasure hunting, Bluenet.

Olp: an R package for optimal linear partitions of finite sets of points on the plane.

Given a set of points on the plane and an assignment of values to them, an optimal linear partition is a division of the set into two subsets which are separated by a straight line and maximally contrast with each other in the values assigned to their points. We present a method for inspecting and rating all linear partitions of a finite set, and a package of three functions in the R language for executing the computations. One function is for finding the optimal linear partitions and corresponding separating lines, another for graphically representing the results, and a third for testing how well the data comply with the linear separability condition. We illustrate the method on possible data from a psychophysical experiment (concerning the size-weight illusion) and compare its performance with that of linear discriminant analysis and multiple logistic regression, adapted to dividing linearly a set of points on the plane.

On the meaning of statements in psychophysics characterizing conditional indeterminacy of percepts

We propose a conceptual framework for the interpretation of statements in the psychophysical literature (especially concerning spatial vision) that represent a combinatorial (rather than probabilistic) way of evaluating the strength of stimulus-percept relationships. First, we introduce elementary set-theoretic guidelines (section 2), and then we explain some exemplary statements from psychophysics following those lines (section 3). After that, we discuss five basic questions which are implied by the assumptions in the conceptual framework and appear crucial for its prospects (section 4). Lastly, we highlight some peculiarities of the framework by a comparison with the probabilistic approach in vision psychophysics (section 5).

Perceptual Slant Induced through Optical Contact

Stimuli simulating a corridor with a pole inside it were presented. The positions of the ends of the pole within the ceiling and ground of the corridor were the optical contacts of concern. The main hypothesis was that a difference between the simulated distances of these optical contacts may influence the apparent slant in depth of the pole. Two experiments were conducted, with 30 and 20 participants (university students). The tasks were a choice between three alternative responses (upward, downward, or no apparent slant) in the first experiment and matching by adjustment in the second. The results supported the hypothesized dependence of apparent slant on differences in optical contacts. The results also revealed a dependence of apparent slant on the interaction between the optical tilt of the pole and its position to the right or left of the vertical median through the stimulus. Comparisons between both effects showed that they combine in a cumulative way and that the former is weightier than the latter. Further findings were a privileged association between null optical tilt of the pole and the no apparent slant response and a bias (for poles with nonnull optical tilt) in favor of the upward apparent slant response.