Activity Number:
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399
- ASA Statistics in Imaging Section Student Paper Competition
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Type:
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Topic Contributed
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Date/Time:
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Tuesday, August 1, 2017 : 2:00 PM to 3:50 PM
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Sponsor:
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Section on Statistics in Imaging
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Abstract #322713
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View Presentation
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Title:
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Evolutionary State-Space Model and Its Application to Time-Frequency Analysis of Local Field Potentials
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Author(s):
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Xu Gao* and Babak Shahbaba and Norbert Fortin and Hernando Ombao
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Companies:
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and University of California, Irvine and University of California, Irvine and KAUST and UC Irvine
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Keywords:
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Auto-regressive model ;
brain signals ;
spectral analysis ;
state-space models ;
time frequency analysis
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Abstract:
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We develop a model for high dimensional signals driven by sources whose properties evolve over epochs in experiments. We propose the evolutionary state space model(E-SSM) where signals are mixtures of sources having oscillatory activity at defined frequency bands. One unique feature in E-SSM is that sources are parametrized as second order autoregressive AR(2) processes. To account for non-stationarity, the AR(2) parameters are allowed to vary over epochs. In contrast to independent component analysis, our method captures the temporal structure. Compared to data-adaptive strategies such as filtering, E-SSM easily accommodates non-stationarity. To estimate our model, we use Kalman smoother, maximum likelihood and blocked resampling approaches. The E-SSM is applied to a multi-epoch LFP signals from an olfactory encoding task. Our method captures the evolution of power of different sources across encoding phases. The E-SSM model also identifies clusters of tetrodes that behave similarly.
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Authors who are presenting talks have a * after their name.