Algorithms that must deal with complicated global functions of many variables often exploit the manner in which the given functions factor as a product of \u201clocal\u201d functions, each of which depends on a subset of the variables. Such a factorization can be visualized with a bipartite graph that we call a factor graph, In this tutorial paper, we present a generic message-passing algorithm, the sum-product algorithm, that operates in a factor graph. Following a single, simple computational rule, the sum-product algorithm computes-either exactly or approximately-various marginal functions derived from the global function. A wide variety of algorithms developed in artificial intelligence, signal processing, and digital communications can be derived as specific instances of the sum-product algorithm, including the forward\/backward algorithm, the Viterbi algorithm, the iterative \u201cturbo\u201d decoding algorithm, Pearl’s (1988) belief propagation algorithm for Bayesian networks, the Kalman filter, and certain fast Fourier transform (FFT) algorithms<\/p><\/blockquote>\n
Please feel free to start the discussion in the comments section below. <\/p>\n","protected":false},"excerpt":{"rendered":"
Dear Journal Club members, Our next meeting will be on March 14th, at noon in room 3160 of the Discovery Building. For this meeting we have selected the a paper by Kschischang et al, Factor graphs and the sum-product algorithm from IEEE. The abstract is presented below. Algorithms that must deal with complicated global functions […]<\/p>\n","protected":false},"author":124,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[102,98,1],"tags":[],"_links":{"self":[{"href":"https:\/\/blogs.discovery.wisc.edu\/sysbiojournalclub\/wp-json\/wp\/v2\/posts\/366"}],"collection":[{"href":"https:\/\/blogs.discovery.wisc.edu\/sysbiojournalclub\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.discovery.wisc.edu\/sysbiojournalclub\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.discovery.wisc.edu\/sysbiojournalclub\/wp-json\/wp\/v2\/users\/124"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.discovery.wisc.edu\/sysbiojournalclub\/wp-json\/wp\/v2\/comments?post=366"}],"version-history":[{"count":2,"href":"https:\/\/blogs.discovery.wisc.edu\/sysbiojournalclub\/wp-json\/wp\/v2\/posts\/366\/revisions"}],"predecessor-version":[{"id":369,"href":"https:\/\/blogs.discovery.wisc.edu\/sysbiojournalclub\/wp-json\/wp\/v2\/posts\/366\/revisions\/369"}],"wp:attachment":[{"href":"https:\/\/blogs.discovery.wisc.edu\/sysbiojournalclub\/wp-json\/wp\/v2\/media?parent=366"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.discovery.wisc.edu\/sysbiojournalclub\/wp-json\/wp\/v2\/categories?post=366"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.discovery.wisc.edu\/sysbiojournalclub\/wp-json\/wp\/v2\/tags?post=366"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}