Exponential distribution

probability distribution

The exponential distribution with rate , written ,[1] is a probability distribution defined only on the positive real numbers. It is the continuous analogue of geometric distribution.[2] Exponential distribution is used in reliability applications,[3] and its main use is to assess the duration of random time intervals. Examples where it can be used include:

  • Time length of a telephone call
  • How long does it take to perform a service (for example, to fix something at a service point)
  • Amount of time between two phone calls
  • Half life of atoms (radioactive decay)
  • Expected lifetime of electronic (or other) parts, if wearing is not considered (this is called Mean Time Between Failures, MTBF)
  • Age of plants or animals
  • Very simple model used by insurance companies
Typical exponential distribution curves

Related pagesEdit


  1. "List of Probability and Statistics Symbols". Math Vault. 2020-04-26. Retrieved 2020-09-22.
  2. Weisstein, Eric W. "Exponential Distribution". mathworld.wolfram.com. Retrieved 2020-09-22.
  3. " Exponential Distribution". itl.nist.gov. Retrieved 2020-09-22.

Other websitesEdit