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  2. Loss functions for classification - Wikipedia

    en.wikipedia.org/wiki/Loss_functions_for...

    A loss function is said to be classification-calibrated or Bayes consistent if its optimal is such that / = ⁡ (()) and is thus optimal under the Bayes decision rule. A Bayes consistent loss function allows us to find the Bayes optimal decision function by directly minimizing the expected risk and without having to explicitly model the ...

  3. Logistic regression - Wikipedia

    en.wikipedia.org/wiki/Logistic_regression

    Log loss is always greater than or equal to 0, equals 0 only in case of a perfect prediction (i.e., when = and =, or = and =), and approaches infinity as the prediction gets worse (i.e., when = and or = and ), meaning the actual outcome is "more surprising". Since the value of the logistic function is always strictly between zero and one, the ...

  4. Decision tree learning - Wikipedia

    en.wikipedia.org/wiki/Decision_tree_learning

    Decision tree learning is a method commonly used in data mining. [3] The goal is to create a model that predicts the value of a target variable based on several input variables. A decision tree is a simple representation for classifying examples.

  5. Decision tree model - Wikipedia

    en.wikipedia.org/wiki/Decision_tree_model

    Decision Tree Model. In computational complexity theory, the decision tree model is the model of computation in which an algorithm can be considered to be a decision tree, i.e. a sequence of queries or tests that are done adaptively, so the outcome of previous tests can influence the tests performed next.

  6. Decision tree - Wikipedia

    en.wikipedia.org/wiki/Decision_tree

    Decision trees, influence diagrams, utility functions, and other decision analysis tools and methods are taught to undergraduate students in schools of business, health economics, and public health, and are examples of operations research or management science methods. These tools are also used to predict decisions of householders in normal and ...

  7. Cross-entropy - Wikipedia

    en.wikipedia.org/wiki/Cross-entropy

    This is also known as the log loss (or logarithmic loss [4] or logistic loss); [5] the terms "log loss" and "cross-entropy loss" are used interchangeably. [ 6 ] More specifically, consider a binary regression model which can be used to classify observations into two possible classes (often simply labelled 0 {\displaystyle 0} and 1 ...

  8. Loss function - Wikipedia

    en.wikipedia.org/wiki/Loss_function

    In many applications, objective functions, including loss functions as a particular case, are determined by the problem formulation. In other situations, the decision maker’s preference must be elicited and represented by a scalar-valued function (called also utility function) in a form suitable for optimization — the problem that Ragnar Frisch has highlighted in his Nobel Prize lecture. [4]

  9. Kullback–Leibler divergence - Wikipedia

    en.wikipedia.org/wiki/Kullback–Leibler_divergence

    This example uses the natural log with base e, ... is itself such a measurement (formally a loss function), ... Information gain in decision trees;