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  2. Standard error - Wikipedia

    en.wikipedia.org/wiki/Standard_error

    For correlated random variables the sample variance needs to be computed according to the Markov chain central limit theorem.. Independent and identically distributed random variables with random sample size

  3. Central limit theorem - Wikipedia

    en.wikipedia.org/wiki/Central_limit_theorem

    The input into the normalized Gaussian function is the mean of sample means (~50) and the mean sample standard deviation divided by the square root of the sample size (~28.87/ √ n), which is called the standard deviation of the mean (since it refers to the spread of sample means).

  4. Fisher's exact test - Wikipedia

    en.wikipedia.org/wiki/Fisher's_exact_test

    Fisher's exact 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. It is named after its inventor, Ronald Fisher, and is one of a class of exact tests, so called because the significance of the deviation ...

  5. Sampling error - Wikipedia

    en.wikipedia.org/wiki/Sampling_error

    The cost of increasing a sample size may be prohibitive in reality. ... of an estimator against the predicted cost of taking a larger sample. Bootstrapping and ...

  6. Student's t-test - Wikipedia

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

    where n is the sample size, x is the vector of column means and S is an m × m sample covariance matrix. For a two-sample multivariate test, the hypothesis is that the mean vectors (μ 1, μ 2) of two samples are equal. The test statistic is Hotelling's two-sample t 2:

  7. Margin of error - Wikipedia

    en.wikipedia.org/wiki/Margin_of_error

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  8. Standard deviation - Wikipedia

    en.wikipedia.org/wiki/Standard_deviation

    The standard deviation σ of X is defined as which can be shown to equal. Using words, the standard deviation is the square root of the variance of X . The standard deviation of a probability distribution is the same as that of a random variable having that distribution. Not all random variables have a standard deviation.

  9. Unbiased estimation of standard deviation - Wikipedia

    en.wikipedia.org/wiki/Unbiased_estimation_of...

    Bias in standard deviation for autocorrelated data. The figure shows the ratio of the estimated standard deviation to its known value (which can be calculated analytically for this digital filter), for several settings of α as a function of sample size n. Changing α alters the variance reduction ratio of the filter, which is known to be