support vector machine - taoualiw/My-Knowledge-Base GitHub Wiki
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Looks for a line that separates classes
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Inherently do binary classification, but may be extended
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Line that maximize distance (MARGIN) to nearest point : robustness of result
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First correct classification then maximize margin
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Ability to ignore outliers
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Decision Boundary : Line or a hyperplane. To generalize the simple idea of finding the linear separation to non-linear boundary the solution is to move to a different feature space where features are linearly separable than back to original features) using the kernel parameter. For example, by adding a feature z ($ z = x^2 + y^2 $), SVM is able to find non linear separations such as center-surround separation.
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Parameters : kernel, C, gamma
- C : controls tradeoff between smooth decision boundary (low C) and classifying training points correctly (high C)
- Gamma : defines how far the influence of a single training example reaches the boundary. (low values -far, high values - close)
- kernel: tranforms inseparable features to separable features