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  2. Z-test - Wikipedia

    en.wikipedia.org/wiki/Z-test

    The term " Z -test" is often used to refer specifically to the one-sample location test comparing the mean of a set of measurements to a given constant when the sample variance is known. For example, if the observed data X1, ..., Xn are (i) independent, (ii) have a common mean μ, and (iii) have a common variance σ 2, then the sample average X ...

  3. Sobel test - Wikipedia

    en.wikipedia.org/wiki/Sobel_test

    In statistics, the Sobel test is a method of testing the significance of a mediation effect. The test is based on the work of Michael E. Sobel, [1][2] and is an application of the delta method. In mediation, the relationship between the independent variable and the dependent variable is hypothesized to be an indirect effect that exists due to ...

  4. Paired difference test - Wikipedia

    en.wikipedia.org/wiki/Paired_difference_test

    A paired difference test is designed for situations where there is dependence between pairs of measurements (in which case a test designed for comparing two independent samples would not be appropriate). That applies in a within-subjects study design, i.e., in a study where the same set of subjects undergo both of the conditions being compared.

  5. Permutation test - Wikipedia

    en.wikipedia.org/wiki/Permutation_test

    A permutation test (also called re-randomization test or shuffle test) is an exact statistical hypothesis test making use of the proof by contradiction. A permutation test involves two or more samples. The null hypothesis is that all samples come from the same distribution . Under the null hypothesis, the distribution of the test statistic is ...

  6. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    Sample size determination. Sample size determination or estimation is the act of choosing the number of observations or replicates to include in a statistical sample. The sample size is an important feature of any empirical study in which the goal is to make inferences about a population from a sample. In practice, the sample size used in a ...

  7. Binomial test - Wikipedia

    en.wikipedia.org/wiki/Binomial_test

    The binomial test is useful to test hypotheses about the probability ( ) of success: where is a user-defined value between 0 and 1. If in a sample of size there are successes, while we expect , the formula of the binomial distribution gives the probability of finding this value: {\displaystyle \Pr (X=k)= {\binom {n} {k}}p^ {k} (1-p)^ {n-k}}

  8. PSPP - Wikipedia

    en.wikipedia.org/wiki/PSPP

    PSPP. PSPP is a free software application for analysis of sampled data, intended as a free alternative for IBM SPSS Statistics. It has a graphical user interface [2] and conventional command-line interface. It is written in C and uses GNU Scientific Library for its mathematical routines. The name has "no official acronymic expansion".

  9. Sequential analysis - Wikipedia

    en.wikipedia.org/wiki/Sequential_analysis

    In a randomized trial with two treatment groups, group sequential testing may for example be conducted in the following manner: After n subjects in each group are available an interim analysis is conducted. A statistical test is performed to compare the two groups and if the null hypothesis is rejected the trial is terminated; otherwise, the ...