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Measuring the accuracy of a classifier allows a choice to be made between two alternative classifiers. This is important both when developing a classifier and in choosing which classifier to deploy. There are however many different methods for evaluating the accuracy of a classifier and no general
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The meaning of the word 'classification' (and its synonyms) may take on one of several related meanings. It may encompass both classification and the creation of classes, as for example in 'the task of categorizing pages in
Knowledge'; this overall activity is listed under
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Classifier accuracy depends greatly on the characteristics of the data to be classified. There is no single classifier that works best on all given problems (a phenomenon that may be explained by the
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is the activity of assigning objects to some pre-existing classes or categories. This is distinct from the task of establishing the classes themselves (for example through
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As well as 'category', synonyms or near-synonyms for 'class' include 'type', 'species', 'order', 'concept', 'taxon', 'group', 'identification' and 'division'.
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method for determining which method should be used in which circumstances. Different fields have taken different approaches, even in binary classification. In
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Methodological work aimed at improving the accuracy of a classifier is commonly divided between cases where there are exactly two classes (
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Classification is a part of many different kinds of activities and is studied from many different points of view including
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scale. Thus it is possible to try to measure the accuracy of a classifier.
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