enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Median test - Wikipedia

    en.wikipedia.org/wiki/Median_test

    Median test (also Mood’s median-test, Westenberg-Mood median test or Brown-Mood median test) is a special case of Pearson's chi-squared test. It is a nonparametric test that tests the null hypothesis that the medians of the populations from which two or more samples are drawn are identical. The data in each sample are assigned to two groups ...

  3. Zero-inflated model - Wikipedia

    en.wikipedia.org/wiki/Zero-inflated_model

    Count data can take values of 0, 1, 2, … (non-negative integer values). [2] Other examples of count data are the number of hits recorded by a Geiger counter in one minute, patient days in the hospital, goals scored in a soccer game, [3] and the number of episodes of hypoglycemia per year for a patient with diabetes. [4]

  4. Index of dispersion - Wikipedia

    en.wikipedia.org/wiki/Index_of_dispersion

    In probability theory and statistics, the index of dispersion, [1] dispersion index, coefficient of dispersion, relative variance, or variance-to-mean ratio (VMR), like the coefficient of variation, is a normalized measure of the dispersion of a probability distribution: it is a measure used to quantify whether a set of observed occurrences are clustered or dispersed compared to a standard ...

  5. Median - Wikipedia

    en.wikipedia.org/wiki/Median

    1, 2, 2, 2, 3, 14. The median is 2 in this case, as is the mode, and it might be seen as a better indication of the center than the arithmetic mean of 4, which is larger than all but one of the values. However, the widely cited empirical relationship that the mean is shifted "further into the tail" of a distribution than the median is not ...

  6. Central tendency - Wikipedia

    en.wikipedia.org/wiki/Central_tendency

    The function corresponding to the L 0 space is not a norm, and is thus often referred to in quotes: 0-"norm". In equations, for a given (finite) data set X , thought of as a vector x = ( x 1 ,…, x n ) , the dispersion about a point c is the "distance" from x to the constant vector c = ( c ,…, c ) in the p -norm (normalized by the number of ...

  7. Median absolute deviation - Wikipedia

    en.wikipedia.org/wiki/Median_absolute_deviation

    In statistics, the median absolute deviation (MAD) is a robust measure of the variability of a univariate sample of quantitative data.It can also refer to the population parameter that is estimated by the MAD calculated from a sample.

  8. Weighted median - Wikipedia

    en.wikipedia.org/wiki/Weighted_median

    The lower weighted median is 2 with partition sums of 0.49 and 0.5, and the upper weighted median is 3 with partition sums of 0.5 and 0.25. In the case of working with integers or non-interval measures, the lower weighted median would be accepted since it is the lower weight of the pair and therefore keeps the partitions most equal. However, it ...

  9. Sample mean and covariance - Wikipedia

    en.wikipedia.org/wiki/Sample_mean_and_covariance

    The sample mean is the average of the values of a variable in a sample, which is the sum of those values divided by the number of values. Using mathematical notation, if a sample of N observations on variable X is taken from the population, the sample mean is: