BrainBasher: a BCI Game

Brain-computer interaction (BCI) is starting to focus on healthy subjects. This research adresses the effects of using this novel input modality to control a simple game, and also looks into the beneficial effects of bringing game elements into BCI experiments. A simple BCI game has been developed and evaluated with fifteen subjects using the Game Experience Questionnaire (GEQ) developed at the Eindhoven Game Experience Lab. Three variations of the game were evaluated for comparison: the original game with BCI input, one with keyboard input, and one with a more clinical look leaving out all extraneous information. The keyboard-controlled game was considered easy and boring, whereas using BCI for input resulted in a more challenging, immersive and richer experience. The design and additional information presented by the game also resulted in higher immersion compared to the clinical design

Is there a single frontier in a single European banking market?

This paper attempts to estimate comparable efficiency scores for European banks operating in the Single Market in the EU. Using a data set of more than 5000 large commercial banks from all major European banking markets over the period 1993-2004, the application of meta-frontiers enables us to assess the existence of a single and integrated European banking market. We find evidence in favor of a single European banking market characterized by cost and profit meta-frontiers. However, compared to the meta-frontier estimations, pooled frontier estimations tend to underestimate efficiency levels and correlate poorly with country-specific frontier efficiency ranks. JEL Classification: G21, L11, L22, L23banking, meta-frontiers, stochastic frontiers, technology gap ratios, X-efficiency

Actual and Imagined Movement in BCI Gaming

Most research on Brain-Computer Interfaces (BCI) focuses\ud on developing ways of expression for disabled people who are\ud not able to communicate through other means. Recently it has been\ud shown that BCI can also be used in games to give users a richer experience\ud and new ways to interact with a computer or game console.\ud This paper describes research conducted to find out what the differences\ud are between using actual and imagined movement as modalities\ud in a BCI game. Results show that there are significant differences\ud in user experience and that actual movement is a more robust way of\ud communicating through a BCI

Wess-Zumino-Witten model off criticality

We study the renormalization group flow properties of the Wess-Zumino-Witten model in the region of couplings between $g^2=0$ and $g^2=4\pi/k$, by evaluating the two-loop Zamolodchikov's $c$-function. We also discuss the region of negative couplings.Comment: 8 page

How much control is enough? Optimizing fun with unreliable input

Brain-computer interfaces (BCI) provide a valuable new input modality within human- computer interaction systems, but like other body-based inputs, the system recognition of input commands is far from perfect. This raises important questions, such as: What level of control should such an interface be able to provide? What is the relationship between actual and perceived control? And in the case of applications for entertainment in which fun is an important part of user experience, should we even aim for perfect control, or is the optimum elsewhere? In this experiment the user plays a simple game in which a hamster has to be guided to the exit of a maze, in which the amount of control the user has over the hamster is varied. The variation of control through confusion matrices makes it possible to simulate the experience of using a BCI, while using the traditional keyboard for input. After each session the user �lled out a short questionnaire on fun and perceived control. Analysis of the data showed that the perceived control of the user could largely be explained by the amount of control in the respective session. As expected, user frustration decreases with increasing control. Moreover, the results indicate that the relation between fun and control is not linear. Although in the beginning fun does increase with improved control, the level of fun drops again just before perfect control is reached. This poses new insights for developers of games wanting to incorporate some form of BCI in their game: for creating a fun game, unreliable input can be used to create a challenge for the user

Origin of Lagrangian Intermittency in Drift-Wave Turbulence

The Lagrangian velocity statistics of dissipative drift-wave turbulence are investigated. For large values of the adiabaticity (or small collisionality), the probability density function of the Lagrangian acceleration shows exponential tails, as opposed to the stretched exponential or algebraic tails, generally observed for the highly intermittent acceleration of Navier-Stokes turbulence. This exponential distribution is shown to be a robust feature independent of the Reynolds number. For small adiabaticity, algebraic tails are observed, suggesting the strong influence of point-vortex-like dynamics on the acceleration. A causal connection is found between the shape of the probability density function and the autocorrelation of the norm of the acceleration

Cross-lingual Question Answering with QED

We present improvements and modifications of the QED open-domain question answering system developed for TREC-2003 to make it cross-lingual for participation in the CrossLinguistic Evaluation Forum (CLEF) Question Answering Track 2004 for the source languages French and German and the target language English. We use rule-based question translation extended with surface pattern-oriented pre- and post-processing rules for question reformulation to create and English query from its French or German original. Our system uses deep processing for the question and answers, which requires efficient and radical prior search space pruning. For answering factoid questions, we report an accuracy of 16% (German to English) and 20% (French to English), respectively