ABSTRACT:
Recently, many applications for the Restricted Boltzmann Machine (RBM) have been
developed for a large variety of problems. However, RBMs are typically not
considered as stand-alone solutions to classification problems, but are instead used
as feature extractors for some other learning algorithm or to provide a good
initialization for deep feed-forward neural network classifiers.
In this talk, I will argue that an RBM can directly address the problem of
classification through its extension: the Classification Restricted Boltzmann
Machine (ClassRBM). I will present different algorithms for training the ClassRBM,
discuss the concepts of discriminative and generative learning and explain how they
can be combined to obtain improved performances. I'll also cover the standard
setting of multi-class classification as well as the semi-supervised and multi-task
(or multi-label) settings. Using these algorithms, state of the art performances can
be achieved by the ClassRBM on a variety of datasets, such as image, text document
and music audio clip classification problems.
Finally, I'll describe a further extension for vision tasks, in which simulated eye
fixations can be combined to classify images. This approach allows the model to
ignore irrelevant parts of an image and focus on its informative regions. An
application to facial expression recognition will be presented.
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