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Cobweb (clustering)
COBWEB is an incremental system for hierarchical conceptual clustering. COBWEB was invented by Professor Douglas H. Fisher, currently at Vanderbilt University. COBWEB incrementally organizes observations into a classification tree Classification chart or classification tree is a synopsis of the classification scheme, designed to illustrate the structure of any particular field. Overview Classification is the process in which ideas and objects are recognized, differentia .... Each node in a classification tree represents a class (concept) and is labeled by a probabilistic concept that summarizes the attribute-value distributions of objects classified under the node. This classification tree can be used to predict missing attributes or the class of a new object. There are four basic operations COBWEB employs in building the classification tree. Which operation is selected depends on the category utility of the classification achieved by applying it. The operations are: * Mergi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conceptual Clustering
Conceptual clustering is a machine learning paradigm for unsupervised classification that has been defined by Ryszard S. Michalski in 1980 (Fisher 1987, Michalski 1980) and developed mainly during the 1980s. It is distinguished from ordinary data clustering by generating a concept description for each generated class. Most conceptual clustering methods are capable of generating hierarchical category structures; see Categorization for more information on hierarchy. Conceptual clustering is closely related to formal concept analysis, decision tree learning, and mixture model learning. Conceptual clustering vs. data clustering Conceptual clustering is obviously closely related to data clustering; however, in conceptual clustering it is not only the inherent structure of the data that drives cluster formation, but also the Description language which is available to the learner. Thus, a statistically strong grouping in the data may fail to be extracted by the learner if the prev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Douglas H
Douglas may refer to: People * Douglas (given name) * Douglas (surname) Animals *Douglas (parrot), macaw that starred as the parrot ''Rosalinda'' in Pippi Longstocking *Douglas the camel, a camel in the Confederate Army in the American Civil War Businesses * Douglas Aircraft Company * Douglas (cosmetics), German cosmetics retail chain in Europe * Douglas (motorcycles), British motorcycle manufacturer Peerage and Baronetage * Duke of Douglas * Earl of Douglas, or any holder of the title * Marquess of Douglas, or any holder of the title * Douglas Baronets Peoples * Clan Douglas, a Scottish kindred * Dougla people, West Indians of both African and East Indian heritage Places Australia * Douglas, Queensland, a suburb of Townsville * Douglas, Queensland (Toowoomba Region), a locality * Port Douglas, North Queensland, Australia * Shire of Douglas, in northern Queensland Belize * Douglas, Belize Canada * Douglas, New Brunswick * Douglas Parish, New Brunswick * Douglas, O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Classification Tree
Classification chart or classification tree is a synopsis of the classification scheme, designed to illustrate the structure of any particular field. Overview Classification is the process in which ideas and objects are recognized, differentiated, and understood, and classification charts are intended to help create and eventually visualize the outcome. According to Brinton "in a classification chart the facts, data etc. are arranged so that the place of each in relation to all others is readily seen. Quantities need not be given, although a quantitative analysis adds to the value of a classification chart." Willard Cope Brinton, ''Graphic presentation.'' 1939. p. 43 Karsten (1923) explained, that "in all chart-making, the material to be shown must be accurately compiled before it can be charted. For an understanding of the classification chart, we must delve somewhat into the mysteries of the classification and indexing. The art of classification calls into play the power of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Category Utility
Category utility is a measure of "category goodness" defined in and . It attempts to maximize both the probability that two objects in the same category have attribute values in common, and the probability that objects from different categories have different attribute values. It was intended to supersede more limited measures of category goodness such as " cue validity" (; ) and "collocation index" . It provides a normative information-theoretic measure of the ''predictive advantage'' gained by the observer who possesses knowledge of the given category structure (i.e., the class labels of instances) over the observer who does ''not'' possess knowledge of the category structure. In this sense the motivation for the category utility measure is similar to the information gain metric used in decision tree learning. In certain presentations, it is also formally equivalent to the mutual information, as discussed below. A review of category utility in its probabilistic incarnation, with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
