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  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. Differential item functioning - Wikipedia

    en.wikipedia.org/wiki/Differential_item_functioning

    The MH procedure is a chi-squared contingency table based approach which examines differences between the reference and focal groups on all items of the test, one by one. [14] The ability continuum, defined by total test scores, is divided into k intervals which then serves as the basis for matching members of both groups. [ 15 ]

  4. Acceptance sampling - Wikipedia

    en.wikipedia.org/wiki/Acceptance_sampling

    MIL-STD-105E was cancelled in 1995 but is available in related documents such as ANSI/ASQ Z1.4, "Sampling Procedures and Tables for Inspection by Attributes". Several levels of inspection are provided and can be indexed to several AQLs. The sample size is specified and the basis for acceptance or rejection (number of defects) is provided. MIL ...

  5. Lot quality assurance sampling - Wikipedia

    en.wikipedia.org/wiki/Lot_Quality_Assurance_Sampling

    Lot quality assurance sampling (LQAS) is a random sampling methodology, originally developed in the 1920s [1] as a method of quality control in industrial production. Compared to similar sampling techniques like stratified and cluster sampling, LQAS provides less information but often requires substantially smaller sample sizes.

  6. Analytical quality control - Wikipedia

    en.wikipedia.org/wiki/Analytical_quality_control

    All analytical procedures should be validated. Identification tests are conducted to ensure the identity of an analyte in a sample through comparison of the sample to a reference standard through methods such as spectrum, chromatographic behavior, and chemical reactivity. [5] Impurity testing can either be a quantitative test or a limit test.

  7. Analysis of variance - Wikipedia

    en.wikipedia.org/wiki/Analysis_of_variance

    Reporting sample size analysis is generally required in psychology. "Provide information on sample size and the process that led to sample size decisions." [45] The analysis, which is written in the experimental protocol before the experiment is conducted, is examined in grant applications and administrative review boards.

  8. Z-test - Wikipedia

    en.wikipedia.org/wiki/Z-test

    A t-test can be used to account for the uncertainty in the sample variance when the data are exactly normal. Difference between Z-test and t-test: Z-test is used when sample size is large (n>50), or the population variance is known. t-test is used when sample size is small (n<50) and population variance is unknown.

  9. Consistency (statistics) - Wikipedia

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

    For example, records for rainfall within an area might increase in three ways: records for additional time periods; records for additional sites with a fixed area; records for extra sites obtained by extending the size of the area. In such cases, the property of consistency may be limited to one or more of the possible ways a sample size can grow.