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Unsupervised categorization of images or image parts is often needed for image and video summarization or as a preprocessing step in supervised methods for classification, tracking and segmentation. While many metric-based techniques have been applied to this problem in the vision community, often, the most natural measures of similarity (e.g., number of(More)
Clustering is a fundamental problem in machine learning and has been approached in many ways. Two general and quite different approaches include iteratively fitting a mixture model (e.g., using EM) and linking together pairs of training cases that have high affinity (e.g., using spectral methods). Pair-wise clustering algorithms need not compute sufficient(More)
MOTIVATION We address the problem of multi-way clustering of microarray data using a generative model. Our algorithm, probabilistic sparse matrix factorization (PSMF), is a probabilistic extension of a previous hard-decision algorithm for this problem. PSMF allows for varying levels of sensor noise in the data, uncertainty in the hidden prototypes used to(More)
Effective visualization of biological data is often critical for subsequent analysis. The popular clustergram/dendrogram visualization rearranges rows and columns of a data matrix so as to highlight clusters of similar responses, but assumes each row or column belongs to only one cluster and cannot associate each row or column with multiple clusters. Such(More)
A key problem of interest to biologists and medical researchers is the selection of a subset of queries or treatments that provide maximum utility for a population of targets. For example, when studying how gene deletion mutants respond to each of thousands of drugs, it is desirable to identify a small subset of genes that nearly uniquely define a drug(More)
Colorectal cancer has a high incidence of morbidity and mortality in the North American population. Elevated levels of plasmalogens have been reported in some neoplastic tissues including colon tumors, but the mechanism for this increase has not been defined. Since changes in plasmalogen level are usually associated with changes in the other phospholipid(More)