Contents
What does the principle of maximum entropy mean?
The principle of maximum entropy states that the probability distribution which best represents the current state of knowledge about a system is the one with largest entropy, in the context of precisely stated prior data (such as a proposition that expresses testable information).
Why is entropy not a measure of disorder?
The first section shows why the connection isn’t always appropriate. The second section asks: If entropy isn’t a measure of disorder, how did so many scientists get that impression?
A closely related quantity, the relative entropy, is usually defined as the Kullback–Leibler divergence of p from q (although it is sometimes, confusingly, defined as the negative of this). The inference principle of minimizing this, due to Kullback, is known as the Principle of Minimum Discrimination Information .
Is the maximum entropy classifier used in machine learning?
For the classifier in machine learning, see maximum entropy classifier. For other uses, see maximum entropy (disambiguation). This article includes a list of general references, but it remains largely unverified because it lacks sufficient corresponding inline citations. Please help to improve this article by introducing more precise citations.
When to choose the least informative entropy distribution?
According to the principle of maximum entropy, if nothing is known about a distribution except that it belongs to a certain class (usually defined in terms of specified properties or measures), then the distribution with the largest entropy should be chosen as the least-informative default.
Is the maximum entropy distribution an exponential distribution?
In the case of distributions supported on [0,∞), the maximum entropy distribution depends on relationships between the first and second moments. In specific cases, it may be the exponential distribution, or may be another distribution, or may be undefinable.
When does the entropy reach an extremum?
The entropy attains an extremum when the functional derivative is equal to zero: It is an exercise for the reader that this extremum is indeed a maximum. Therefore, the maximum entropy probability distribution in this case must be of the form (
Is the principle of maximum entropy compatible with bayes’theorem?
Giffin and Caticha (2007) state that Bayes’ theorem and the principle of maximum entropy are completely compatible and can be seen as special cases of the “method of maximum relative entropy”. They state that this method reproduces every aspect of orthodox Bayesian inference methods.
Can a Shannon entropy be used for continuous distributions?
For continuous distributions, the Shannon entropy cannot be used, as it is only defined for discrete probability spaces. Instead Edwin Jaynes (1963, 1968, 2003) gave the following formula, which is closely related to the relative entropy (see also differential entropy ).