enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Poisson distribution - Wikipedia

    en.wikipedia.org/wiki/Poisson_distribution

    In probability theory and statistics, the Poisson distribution (/ ˈ p w ɑː s ɒ n /; French pronunciation:) is a discrete probability distribution that expresses the probability of a given number of events occurring in a fixed interval of time if these events occur with a known constant mean rate and independently of the time since the last event. [1]

  3. c-chart - Wikipedia

    en.wikipedia.org/wiki/C-chart

    The Poisson distribution is the basis for the chart and requires the following assumptions: [2] The number of opportunities or potential locations for nonconformities is very large; The probability of nonconformity at any location is small and constant; The inspection procedure is same for each sample and is carried out consistently from sample ...

  4. u-chart - Wikipedia

    en.wikipedia.org/wiki/U-chart

    Monitoring the number of nonconformities per lot of raw material received where the lot size varies; Monitoring the number of new infections in a hospital per day; Monitoring the number of accidents for delivery trucks per day; As with the c-chart, the Poisson distribution is the basis for the chart and requires the same assumptions.

  5. Poisson regression - Wikipedia

    en.wikipedia.org/wiki/Poisson_regression

    In statistics, Poisson regression is a generalized linear model form of regression analysis used to model count data and contingency tables. [1] Poisson regression assumes the response variable Y has a Poisson distribution, and assumes the logarithm of its expected value can be modeled by a linear combination of unknown parameters.

  6. Cumulant - Wikipedia

    en.wikipedia.org/wiki/Cumulant

    The limiting case n −1 = 0 is a Poisson distribution. The negative binomial distributions, (number of failures before r successes with probability p of success on each trial). The special case r = 1 is a geometric distribution. Every cumulant is just r times the corresponding

  7. Poisson sampling - Wikipedia

    en.wikipedia.org/wiki/Poisson_sampling

    The probability of being included in a sample during the drawing of a single sample is denoted as the first-order inclusion probability of that element (). If all first-order inclusion probabilities are equal, Poisson sampling becomes equivalent to Bernoulli sampling , which can therefore be considered to be a special case of Poisson sampling.

  8. Poisson-type random measure - Wikipedia

    en.wikipedia.org/wiki/Poisson-type_random_measure

    Poisson-type random measures are a family of three random counting measures which are closed under restriction to a subspace, i.e. closed under thinning. They are the only distributions in the canonical non-negative power series family of distributions to possess this property and include the Poisson distribution, negative binomial distribution, and binomial distribution. [1]

  9. Ratio estimator - Wikipedia

    en.wikipedia.org/wiki/Ratio_estimator

    where N is the population size, n is the sample size, m x is the mean of the x variate and s x 2 and s y 2 are the sample variances of the x and y variates respectively. These versions differ only in the factor in the denominator (N - 1). For a large N the difference is negligible. If x and y are unitless counts with Poisson distribution a ...