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  2. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    It is usually determined on the basis of the cost, time or convenience of data collection and the need for sufficient statistical power. For example, if a proportion is being estimated, one may wish to have the 95% confidence interval be less than 0.06 units wide. Alternatively, sample size may be assessed based on the power of a hypothesis ...

  3. Statistical significance - Wikipedia

    en.wikipedia.org/wiki/Statistical_significance

    We conclude, based on our review of the articles in this special issue and the broader literature, that it is time to stop using the term "statistically significant" entirely. Nor should variants such as "significantly different," " p ≤ 0.05 {\displaystyle p\leq 0.05} ," and "nonsignificant" survive, whether expressed in words, by asterisks ...

  4. 68–95–99.7 rule - Wikipedia

    en.wikipedia.org/wiki/68–95–99.7_rule

    In statistics, the 68–95–99.7 rule, also known as the empirical rule, and sometimes abbreviated 3sr or 3 σ, is a shorthand used to remember the percentage of values that lie within an interval estimate in a normal distribution: approximately 68%, 95%, and 99.7% of the values lie within one, two, and three standard deviations of the mean ...

  5. Power (statistics) - Wikipedia

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

    To make this more concrete, a typical statistical test would be based on a test statistic t calculated from the sampled data, which has a particular probability distribution under . A desired significance level α would then define a corresponding "rejection region" (bounded by certain "critical values"), a set of values t is unlikely to take ...

  6. p-value - Wikipedia

    en.wikipedia.org/wiki/P-value

    In 2016, the American Statistical Association (ASA) made a formal statement that "p-values do not measure the probability that the studied hypothesis is true, or the probability that the data were produced by random chance alone" and that "a p-value, or statistical significance, does not measure the size of an effect or the importance of a ...

  7. Estimation statistics - Wikipedia

    en.wikipedia.org/wiki/Estimation_statistics

    While historical data-group plots (bar charts, box plots, and violin plots) do not display the comparison, estimation plots add a second axis to explicitly visualize the effect size. [28] The Gardner–Altman plot. Left: A conventional bar chart, using asterisks to show that the difference is 'statistically significant.'

  8. Validity (statistics) - Wikipedia

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

    Validity is based on the strength of a collection of different types of evidence (e.g. face validity, construct validity, etc.) described in greater detail below. In psychometrics , validity has a particular application known as test validity : "the degree to which evidence and theory support the interpretations of test scores" ("as entailed by ...

  9. Statistical conclusion validity - Wikipedia

    en.wikipedia.org/wiki/Statistical_conclusion...

    Statistical conclusion validity is the degree to which conclusions about the relationship among variables based on the data are correct or "reasonable". This began as being solely about whether the statistical conclusion about the relationship of the variables was correct, but now there is a movement towards moving to "reasonable" conclusions that use: quantitative, statistical, and ...