Højen-Sørensen, Pedro A. d. F. R.
Ensemble Learning and Linear Response Theory for ICA
Højen-Sørensen, Pedro A. d. F. R., Winther, Ole, Hansen, Lars Kai
Ensemble Learning and Linear Response Theory for ICA
Højen-Sørensen, Pedro A. d. F. R., Winther, Ole, Hansen, Lars Kai
We propose a general Bayesian framework for performing independent (leA) which relies on ensemble learning and linearcomponent analysis response theory known from statistical physics. We apply it to both discrete and continuous sources. For the continuous source the underdetermined (overcomplete) case is studied. The naive mean-field approach fails in this case whereas linear response theory-which gives an improved estimate of covariances-is very efficient. The examples given are for sources without temporal correlations. However, this derivation can easily to treat temporal correlations. Finally, the frameworkbe extended of generating new leA algorithms without needingoffers a simple way to define the prior distribution of the sources explicitly.
Ensemble Learning and Linear Response Theory for ICA
Højen-Sørensen, Pedro A. d. F. R., Winther, Ole, Hansen, Lars Kai
Bayesian Modelling of fMRI lime Series
Højen-Sørensen, Pedro A. d. F. R., Hansen, Lars Kai, Rasmussen, Carl Edward
We present a Hidden Markov Model (HMM) for inferring the hidden psychological state (or neural activity) during single trial tMRI activation experiments with blocked task paradigms. Inference is based on Bayesian methodology, using a combination of analytical and a variety of Markov Chain Monte Carlo (MCMC) sampling techniques. The advantage of this method is that detection of short time learning effects between repeated trials is possible since inference is based only on single trial experiments.
Bayesian Modelling of fMRI lime Series
Højen-Sørensen, Pedro A. d. F. R., Hansen, Lars Kai, Rasmussen, Carl Edward
We present a Hidden Markov Model (HMM) for inferring the hidden psychological state (or neural activity) during single trial tMRI activation experiments with blocked task paradigms. Inference is based on Bayesian methodology, using a combination of analytical and a variety of Markov Chain Monte Carlo (MCMC) sampling techniques. The advantage of this method is that detection of short time learning effects between repeated trials is possible since inference is based only on single trial experiments.
Bayesian Modelling of fMRI lime Series
Højen-Sørensen, Pedro A. d. F. R., Hansen, Lars Kai, Rasmussen, Carl Edward
We present a Hidden Markov Model (HMM) for inferring the hidden psychological state (or neural activity) during single trial tMRI activation experimentswith blocked task paradigms. Inference is based on Bayesian methodology, using a combination of analytical and a variety of Markov Chain Monte Carlo (MCMC) sampling techniques. The advantage ofthis method is that detection of short time learning effects between repeated trials is possible since inference is based only on single trial experiments.