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1School of Informatics, University of Edinburgh, Edinburgh EH1 2QL, UK. c.k.i.williams@ed.ac.uk
Neural Computation
|March 23, 2005
Summary
This study explains how "independent" augmented observations, derived from nearby data points, can be coherently modeled. It shows their use in autoregressive processes and the products of experts model.
Area of Science:
- Machine Learning
- Data Modeling
- Statistical Analysis
Background:
- Augmenting data with differences of nearby observations is common in areas like speech recognition and image analysis.
- These augmented observations are frequently modeled as independent, raising questions about their coherence.
Purpose of the Study:
- To provide two interpretations for the coherent modeling of augmented observations.
- To demonstrate how these augmented observations relate to autoregressive processes and expert models.
Main Methods:
- Mathematical derivation showing likelihood computation for autoregressive processes using "independent" augmented observations.
- Application of the products of experts model to provide a coherent framework for augmented observations.
Main Results:
- Demonstrated that the likelihood of autoregressive data can be computed using "independent" augmented observations.
- Established a coherent treatment for augmented observations within the products of experts framework.
Conclusions:
- The apparent independence of augmented observations can be reconciled with underlying data generation processes.
- Provides a theoretical basis for using differenced, "independent" features in complex data modeling tasks.
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