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  2. Z-test - Wikipedia

    en.wikipedia.org/wiki/Z-test

    How to perform a Z test when T is a statistic that is approximately normally distributed under the null hypothesis is as follows: . First, estimate the expected value μ of T under the null hypothesis, and obtain an estimate s of the standard deviation of T.

  3. Null distribution - Wikipedia

    en.wikipedia.org/wiki/Null_distribution

    In statistical hypothesis testing, the null distribution is the probability distribution of the test statistic when the null hypothesis is true. [1] For example, in an F-test, the null distribution is an F-distribution. [2] Null distribution is a tool scientists often use when conducting experiments.

  4. Null hypothesis - Wikipedia

    en.wikipedia.org/wiki/Null_hypothesis

    In scientific research, the null hypothesis (often denoted H 0) [1] is the claim that the effect being studied does not exist. [note 1] The null hypothesis can also be described as the hypothesis in which no relationship exists between two sets of data or variables being analyzed. If the null hypothesis is true, any experimentally observed ...

  5. Test statistic - Wikipedia

    en.wikipedia.org/wiki/Test_statistic

    Test statistic is a quantity derived from the sample for statistical hypothesis testing. [1] A hypothesis test is typically specified in terms of a test statistic, considered as a numerical summary of a data-set that reduces the data to one value that can be used to perform the hypothesis test.

  6. Statistical hypothesis test - Wikipedia

    en.wikipedia.org/wiki/Statistical_hypothesis_test

    The p-value is the probability that a test statistic which is at least as extreme as the one obtained would occur under the null hypothesis. At a significance level of 0.05, a fair coin would be expected to (incorrectly) reject the null hypothesis (that it is fair) in 1 out of 20 tests on average.

  7. Wald test - Wikipedia

    en.wikipedia.org/wiki/Wald_test

    In statistics, the Wald test (named after Abraham Wald) assesses constraints on statistical parameters based on the weighted distance between the unrestricted estimate and its hypothesized value under the null hypothesis, where the weight is the precision of the estimate.

  8. Student's t-test - Wikipedia

    en.wikipedia.org/wiki/Student's_t-test

    Student's t-test is a statistical test used to test whether the difference between the response of two groups is statistically significant or not. It is any statistical hypothesis test in which the test statistic follows a Student's t-distribution under the null hypothesis.

  9. Likelihood-ratio test - Wikipedia

    en.wikipedia.org/wiki/Likelihood-ratio_test

    In statistics, the likelihood-ratio test is a hypothesis test that involves comparing the goodness of fit of two competing statistical models, typically one found by maximization over the entire parameter space and another found after imposing some constraint, based on the ratio of their likelihoods.