logit

The inverse of the sigmoid or logistic function used in mathematics, especially in statistics. The logit of a number p between 0 and 1 is given by the formula:

Noun

  1. The inverse of the sigmoid or logistic function used in mathematics, especially in statistics. The logit of a number p between 0 and 1 is given by the formula:
    • operatorname logit(p)= log (p/(1-p))= log (p)- log (1-p).!,
    • The relation of the logit formula to the distribution of unobserved utility (as opposed to the characteristics of choice probabilities) was developed by Marley, as cited by Luce and Suppes (1965), who showed that the...
    • Improvements in computer speed and in our understanding of simulation methods have allowed the full power of mixed logits to be utilized. - 2002, chapter 6, in Behavioral Models, UC Berkeley, archived from the original...
  2. A logistic regression, which applies such a mathematical function.

Origin

Blend of logistic + unit, by analogy with probit, coined by American statistician Joseph Berkson in 1944: “I use this term [logit] for ln p/q following Bliss, who called the analogous function which is linear on x for the normal curve ‘probit.’”

Forms

logits

Related

probit bit