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  2. Luhn algorithm - Wikipedia

    en.wikipedia.org/wiki/Luhn_algorithm

    Luhn algorithm. The Luhn algorithm or Luhn formula, also known as the " modulus 10" or "mod 10" algorithm, named after its creator, IBM scientist Hans Peter Luhn, is a simple check digit formula used to validate a variety of identification numbers. It is described in US patent 2950048A, granted on 23 August 1960. [ 1]

  3. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    Sample size determination or estimation is the act of choosing the number of observations or replicates to include in a statistical sample. The sample size is an important feature of any empirical study in which the goal is to make inferences about a population from a sample. In practice, the sample size used in a study is usually determined ...

  4. Power (statistics) - Wikipedia

    en.wikipedia.org/wiki/Power_(statistics)

    Power (statistics) In frequentist statistics, power is a measure of the ability of an experimental design and hypothesis testing setup to detect a particular effect if it is truly present. In typical use, it is a function of the test used (including the desired level of statistical significance ), the assumed distribution of the test (for ...

  5. Binomial distribution - Wikipedia

    en.wikipedia.org/wiki/Binomial_distribution

    The binomial distribution is the PMF of k successes given n independent events each with a probability p of success. Mathematically, when α = k + 1 and β = n − k + 1, the beta distribution and the binomial distribution are related by [clarification needed] a factor of n + 1 :

  6. Confidence interval - Wikipedia

    en.wikipedia.org/wiki/Confidence_interval

    A confidence interval for the parameter , with confidence level or coefficient , is an interval determined by random variables and with the property: The number , whose typical value is close to but not greater than 1, is sometimes given in the form (or as a percentage ), where is a small positive number, often 0.05.

  7. Ratio estimator - Wikipedia

    en.wikipedia.org/wiki/Ratio_estimator

    The ratio estimator is a statistical estimator for the ratio of means of two random variables. Ratio estimates are biased and corrections must be made when they are used in experimental or survey work. The ratio estimates are asymmetrical and symmetrical tests such as the t test should not be used to generate confidence intervals.

  8. Kuder–Richardson formulas - Wikipedia

    en.wikipedia.org/wiki/Kuder–Richardson_formulas

    The name of this formula stems from the fact that is the twentieth formula discussed in Kuder and Richardson's seminal paper on test reliability. [1] It is a special case of Cronbach's α, computed for dichotomous scores. [2] [3] It is often claimed that a high KR-20 coefficient (e.g., > 0.90) indicates a homogeneous test. However, like ...

  9. Resident Identity Card - Wikipedia

    en.wikipedia.org/wiki/Resident_Identity_Card

    The Resident Identity Card ( Chinese: 居民身份证; pinyin: Jūmín Shēnfènzhèng) is an official identity document for personal identification in the People's Republic of China. According to the second chapter, tenth clause of the Resident Identity Card Law, residents are required to apply for resident identity cards from the local Public ...