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. Design effect - Wikipedia

    en.wikipedia.org/wiki/Design_effect

    Table 1: Summary of notation ... The effective sample size, defined by Kish in 1965, is calculated by dividing the original sample size by the design effect. [1] ...

  4. Shewhart individuals control chart - Wikipedia

    en.wikipedia.org/wiki/Shewhart_individuals...

    The value 3.267 is taken from the sample size-specific D 4 anti-biasing constant for n=2, as given in most textbooks on statistical process control (see, for example, Montgomery [2]: 725 ). Calculation of individuals control limits

  5. Completely randomized design - Wikipedia

    en.wikipedia.org/wiki/Completely_randomized_design

    and the total sample size (number of runs) is N = k × L × n. Balance dictates that the number of replications be the same at each level of the factor (this will maximize the sensitivity of subsequent statistical t- (or F-) tests).

  6. Sample maximum and minimum - Wikipedia

    en.wikipedia.org/wiki/Sample_maximum_and_minimum

    The sample extrema can be used for a simple normality test, specifically of kurtosis: one computes the t-statistic of the sample maximum and minimum (subtracts sample mean and divides by the sample standard deviation), and if they are unusually large for the sample size (as per the three sigma rule and table therein, or more precisely a Student ...

  7. Effect size - Wikipedia

    en.wikipedia.org/wiki/Effect_size

    In statistics, an effect size is a value measuring the strength of the relationship between two variables in a population, or a sample-based estimate of that quantity. It can refer to the value of a statistic calculated from a sample of data, the value of one parameter for a hypothetical population, or to the equation that operationalizes how statistics or parameters lead to the effect size ...

  8. x̅ and R chart - Wikipedia

    en.wikipedia.org/wiki/X̅_and_R_chart

    The sample size is constant Humans must perform the calculations for the chart As with the x ¯ {\displaystyle {\bar {x}}} and s and individuals control charts , the x ¯ {\displaystyle {\bar {x}}} chart is only valid if the within-sample variability is constant. [ 4 ]

  9. Sample ratio mismatch - Wikipedia

    en.wikipedia.org/wiki/Sample_ratio_mismatch

    The expected size of each group is 500. However, the actual sizes of the treatment and control groups are 600 and 400. Using Pearson's chi-squared goodness of fit test, we find a sample ratio mismatch with a p-value of 2.54 × 10-10.