enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    The table shown on the right can be used in a two-sample t-test to estimate the sample sizes of an experimental group and a control group that are of equal size, that is, the total number of individuals in the trial is twice that of the number given, and the desired significance level is 0.05. [4]

  3. Cohen's h - Wikipedia

    en.wikipedia.org/wiki/Cohen's_h

    Researchers have used Cohen's h as follows.. Describe the differences in proportions using the rule of thumb criteria set out by Cohen. [1] Namely, h = 0.2 is a "small" difference, h = 0.5 is a "medium" difference, and h = 0.8 is a "large" difference.

  4. Completeness (statistics) - Wikipedia

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

    This example will show that, in a sample X 1, X 2 of size 2 from a normal distribution with known variance, the statistic X 1 + X 2 is complete and sufficient. Suppose X 1 , X 2 are independent , identically distributed random variables, normally distributed with expectation θ and variance 1.

  5. Wilks' theorem - Wikipedia

    en.wikipedia.org/wiki/Wilks'_theorem

    The dimensionality of the full parameter space Θ is 2 (either of the and either of the may be treated as free parameters under the hypothesis ), and the dimensionality of is 1 (only one of the may be considered a free parameter under the null hypothesis ).

  6. Bartlett's test - Wikipedia

    en.wikipedia.org/wiki/Bartlett's_test

    This test procedure is based on the statistic whose sampling distribution is approximately a Chi-Square distribution with (k − 1) degrees of freedom, where k is the number of random samples, which may vary in size and are each drawn from independent normal distributions. Bartlett's test is sensitive to departures from normality.

  7. Scale parameter - Wikipedia

    en.wikipedia.org/wiki/Scale_parameter

    Converges as the sample size grows. Various measures of statistical dispersion satisfy these. In order to make the statistic a consistent estimator for the scale parameter, one must in general multiply the statistic by a constant scale factor. This scale factor is defined as the theoretical value of the value obtained by dividing the required ...

  8. L-moment - Wikipedia

    en.wikipedia.org/wiki/L-moment

    Download as PDF; Printable version; ... in an independent sample of size n from the distribution of X and ... ⁠ 15 / 64 ⁠ π = 0.7363 : 0 ⁠ ...

  9. Plackett–Burman design - Wikipedia

    en.wikipedia.org/wiki/Plackett–Burman_design

    Paley's method could be used to find such matrices of size N for most N equal to a multiple of 4. In particular, it worked for all such N up to 100 except N = 92. If N is a power of 2, however, the resulting design is identical to a fractional factorial design , so Plackett–Burman designs are mostly used when N is a multiple of 4 but not a ...