Oceania
The Third International Conference on Case-Based Reasoning (ICCBR 1999)
Althoff, Klaus-Dieter, Bergmann, Ralph, Branting, Karl
The Third International Conference on Case-Based Reasoning was held at the Seeon Monastery, Bavaria, 27 to 30 July 1999. About 120 researchers from 21 countries attended. The conference included 4 workshops; 3 invit-ed talks; 24 technical presentations; a poster session; and an Industry Day, where the focus was on mature technologies and applications in industry.
Review of Conceptual Spaces -- The Geometry of Thought
The second abstract concepts or theoretical predicates, this knowledge can be hand response is to build ontologies, which none of which present themselves coded into machines by experts or has appeal because the fundamental as directly observable quantities even elicited from them by an automated idea is old and tested, witness Linneaus in the databases.
RoboCup-2000: The Fourth Robotic Soccer World Championships
Stone, Peter, Asada, Minoru, Balch, Tucker, D', Andrea, Raffaelo, Fujita, Masahiro, Hengst, Bernhard, Kraetzschmar, Gerhard, Lima, Pedro, Lau, Nuno, Lund, Henrik, Polani, Daniel, Scerri, Paul, Tadokoro, Satoshi, Weigel, Thilo, Wyeth, Gordon
The Fourth Robotic Soccer World Championships (RoboCup-2000) was held from 27 August to 3 September 2000 at the Melbourne Exhibition Center in Melbourne, Australia. In total, 83 teams, consisting of about 500 people, participated in RoboCup-2000, and about 5000 spectators watched the events. RoboCup-2000 showed dramatic improvement over past years in each of the existing robotic soccer leagues (legged, small size, mid size, and simulation) and introduced RoboCup Jr. competitions and RoboCup Rescue and Humanoid demonstration events. The RoboCup Workshop, held in conjunction with the championships, provided a forum for the exchange of ideas and experiences among the different leagues. This article summarizes the advances seen at RoboCup-2000, including reports from the championship teams and overviews of all the RoboCup events.
Evolving Learnable Languages
Tonkes, Bradley, Blair, Alan, Wiles, Janet
Recent theories suggest that language acquisition is assisted by the evolution of languages towards forms that are easily learnable. In this paper, we evolve combinatorial languages which can be learned by a recurrent neural network quickly and from relatively few examples. Additionally, we evolve languages for generalization in different "worlds", and for generalization from specific examples. We find that languages can be evolved to facilitate different forms of impressive generalization for a minimally biased, general purpose learner. The results provide empirical support for the theory that the language itself, as well as the language environment of a learner, plays a substantial role in learning: that there is far more to language acquisition than the language acquisition device.
Neural System Model of Human Sound Localization
This paper examines the role of biological constraints in the human auditory localization process. A psychophysical and neural system modeling approach was undertaken in which performance comparisons between competing models and a human subject explore the relevant biologically plausible "realism constraints". The directional acoustical cues, upon which sound localization is based, were derived from the human subject's head-related transfer functions (HRTFs). Sound stimuli were generated by convolving bandpass noise with the HRTFs and were presented to both the subject and the model. The input stimuli to the model was processed using the Auditory Image Model of cochlear processing. The cochlear data was then analyzed by a time-delay neural network which integrated temporal and spectral information to determine the spatial location of the sound source.
A MCMC Approach to Hierarchical Mixture Modelling
There are many hierarchical clustering algorithms available, but these lack a firm statistical basis. Here we set up a hierarchical probabilistic mixture model, where data is generated in a hierarchical tree-structured manner. Markov chain Monte Carlo (MCMC) methods are demonstrated which can be used to sample from the posterior distribution over trees containing variable numbers of hidden units.
v-Arc: Ensemble Learning in the Presence of Outliers
Rรคtsch, Gunnar, Schรถlkopf, Bernhard, Smola, Alex J., Mรผller, Klaus-Robert, Onoda, Takashi, Mika, Sebastian
The idea of a large minimum margin [17] explains the good generalization performance of AdaBoost in the low noise regime. However, AdaBoost performs worse on noisy tasks [10, 11], such as the iris and the breast cancer benchmark data sets [1]. On the latter tasks, a large margin on all training points cannot be achieved without adverse effects on the generalization error. This experimental observation was supported by the study of [13] where the generalization error of ensemble methods was bounded by the sum of the fraction of training points which have a margin smaller than some value p, say, plus a complexity term depending on the base hypotheses and p. While this bound can only capture part of what is going on in practice, it nevertheless already conveys the message that in some cases it pays to allow for some points which have a small margin, or are misclassified, if this leads to a larger overall margin on the remaining points. To cope with this problem, it was mandatory to construct regularized variants of AdaBoost, which traded off the number of margin errors and the size of the margin 562 G. Riitsch, B. Sch6lkopf, A. J. Smola, K.-R.
Invariant Feature Extraction and Classification in Kernel Spaces
Mika, Sebastian, Rรคtsch, Gunnar, Weston, Jason, Schรถlkopf, Bernhard, Smola, Alex J., Mรผller, Klaus-Robert
In hyperspectral imagery one pixel typically consists of a mixture of the reflectance spectra of several materials, where the mixture coefficients correspond to the abundances of the constituting materials. We assume linear combinations of reflectance spectra with some additive normal sensor noise and derive a probabilistic MAP framework for analyzing hyperspectral data. As the material reflectance characteristics are not know a priori, we face the problem of unsupervised linear unmixing.
Boosting Algorithms as Gradient Descent
Mason, Llew, Baxter, Jonathan, Bartlett, Peter L., Frean, Marcus R.
Recent theoretical results suggest that the effectiveness of these algorithms is due to their tendency to produce large margin classifiers [1, 18]. Loosely speaking, if a combination of classifiers correctly classifies most of the training data with a large margin, then its error probability is small. In [14] we gave improved upper bounds on the misclassification probability of a combined classifier in terms of the average over the training data of a certain cost function of the margins.