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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. Z-test - Wikipedia

   en.wikipedia.org/wiki/Z-test

   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. There is no universal constant at which the sample size is generally considered large enough to justify use of the plug-in test. Typical ...

4. PS Power and Sample Size - Wikipedia

   en.wikipedia.org/wiki/PS_Power_and_Sample_Size

   The program provides methods that are appropriate for matched and independent t-tests, [2] survival analysis, [5] matched [6] and unmatched [7] [8] studies of dichotomous events, the Mantel-Haenszel test, [9] and linear regression. [3] The program can generate graphs of the relationships between power, sample size and the detectable alternative ...

5. Power (statistics) - Wikipedia

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

   According to this formula, the power increases with the values of the effect size and the sample size n, and reduces with increasing variability . In the trivial case of zero effect size, power is at a minimum ( infimum ) and equal to the significance level of the test α , {\displaystyle \alpha \,,} in this example 0.05.

6. Sampling (statistics) - Wikipedia

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

   A probability sample is a sample in which every unit in the population has a chance (greater than zero) of being selected in the sample, and this probability can be accurately determined. The combination of these traits makes it possible to produce unbiased estimates of population totals, by weighting sampled units according to their ...

7. Z-factor - Wikipedia

   en.wikipedia.org/wiki/Z-factor

   The Z-factor defines a characteristic parameter of the capability of hit identification for each given assay. The following categorization of HTS assay quality by the value of the Z-Factor is a modification of Table 1 shown in Zhang et al. (1999); [2] note that the Z-factor cannot exceed one.

8. Fisher's exact test - Wikipedia

   en.wikipedia.org/wiki/Fisher's_exact_test

   Fisher's exact test (also Fisher-Irwin test) is a statistical significance test used in the analysis of contingency tables. [ 1 ] [ 2 ] [ 3 ] Although in practice it is employed when sample sizes are small, it is valid for all sample sizes.

9. Rayleigh test - Wikipedia

   en.wikipedia.org/wiki/Rayleigh_test

   Rayleigh test can refer to: a test for periodicity in irregularly sampled data, [ 1 ] a derivation of the above to test for non-uniformity (as unimodal clustering) of a set of points on a circle (e.g. compass directions), [ 2 ] sometimes known as the Rayleigh z test.