Classification (machine Learning) - Relation To Other Problems

Relation To Other Problems

Classification and clustering are examples of the more general problem of pattern recognition, which is the assignment of some sort of output value to a given input value. Other examples are regression, which assigns a real-valued output to each input; sequence labeling, which assigns a class to each member of a sequence of values (for example, part of speech tagging, which assigns a part of speech to each word in an input sentence); parsing, which assigns a parse tree to an input sentence, describing the syntactic structure of the sentence; etc.

A common subclass of classification is probabilistic classification. Algorithms of this nature use statistical inference to find the best class for a given instance. Unlike other algorithms, which simply output a "best" class, probabilistic algorithms output a probability of the instance being a member of each of the possible classes. The best class is normally then selected as the one with the highest probability. However, such an algorithm has numerous advantages over non-probabilistic classifiers:

  • It can output a confidence value associated with its choice (in general, a classifier that can do this is known as a confidence-weighted classifier)
  • Correspondingly, it can abstain when its confidence of choosing any particular output is too low
  • Because of the probabilities output, probabilistic classifiers can be more effectively incorporated into larger machine-learning tasks, in a way that partially or completely avoids the problem of error propagation.

Read more about this topic:  Classification (machine Learning)

Famous quotes containing the words relation to, relation and/or problems:

    The foregoing generations beheld God and nature face to face; we, through their eyes. Why should not we also enjoy an original relation to the universe? Why should not we have a poetry and philosophy of insight and not of tradition, and a religion by revelation to us, and not the history of theirs?
    Ralph Waldo Emerson (1803–1882)

    Concord is just as idiotic as ever in relation to the spirits and their knockings. Most people here believe in a spiritual world ... in spirits which the very bullfrogs in our meadows would blackball. Their evil genius is seeing how low it can degrade them. The hooting of owls, the croaking of frogs, is celestial wisdom in comparison.
    Henry David Thoreau (1817–1862)

    The problems of all of humanity can only be solved by all of humanity.
    Friedrich Dürrenmatt (1921–1990)