Dik Kin Wong

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While magnetoencephalography (MEG) is widely used to identify spatial locations of brain activations associated with various tasks, classification of single trials in stimulus-locked experiments remains an open subject. Very significant single-trial classification results have been published using electroencephalogram (EEG) data, but in the MEG case, the(More)
The idea of a hierarchical structure of language constituents of phonemes, syllables, words, and sentences is robust and widely accepted. Empirical similarity differences at every level of this hierarchy have been analyzed in the form of confusion matrices for many years. By normalizing such data so that differences are represented by conditional(More)
Significant results for individual trials were achieved in recognizing brain waves using singlechannel perceptron-based classifiers (SCC) on electroencephalography (EEG) data generated by visual sentences as stimuli. By the use of a multichannel classifier (MCC), classification rates were greatly improved for the subjects with bipolar settings, while the(More)
In brain-imaging research, we are often interested in making quantitative claims about effects across subjects. Given that most imaging data consist of tens to thousands of spatially correlated time series, inter-subject comparisons are typically accomplished with simple combinations of inter-subject data, for example methods relying on group means.(More)
Regularization is useful for extending learning models to be effective for classifications. Given the success of regularized-perceptron-based (one-layer neural network) methods, a similar kind of regularization is introduced for two global-optimum approaches recently proposed by Castillo et al., which combined the degree of freedom of using nonlinear(More)
We have previously shown that classification of single-trial electroencephalographic (EEG) recordings is improved by the use of either a niultichannel classifier or the best independent component over a single channel classifier. In this paper, we introduce a classifier that makes explicit use of multiple independent components. Two models are compared. The(More)
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