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  2. Bootstrapping (statistics) - Wikipedia

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

    Bias-corrected bootstrap – adjusts for bias in the bootstrap distribution. Accelerated bootstrap – The bias-corrected and accelerated (BCa) bootstrap, by Efron (1987), adjusts for both bias and skewness in the bootstrap distribution. This approach is accurate in a wide variety of settings, has reasonable computation requirements, and ...

  3. Heckman correction - Wikipedia

    en.wikipedia.org/wiki/Heckman_correction

    The Heckman correction is a two-step M-estimator where the covariance matrix generated by OLS estimation of the second stage is inconsistent. [7] Correct standard errors and other statistics can be generated from an asymptotic approximation or by resampling, such as through a bootstrap. [8]

  4. Jackknife resampling - Wikipedia

    en.wikipedia.org/wiki/Jackknife_resampling

    In statistics, the jackknife (jackknife cross-validation) is a cross-validation technique and, therefore, a form of resampling . It is especially useful for bias and variance estimation. The jackknife pre-dates other common resampling methods such as the bootstrap. Given a sample of size , a jackknife estimator can be built by aggregating the ...

  5. Cluster sampling - Wikipedia

    en.wikipedia.org/wiki/Cluster_sampling

    Several solutions for the small cluster problem have been proposed. One can use a bias-corrected cluster-robust variance matrix, make T-distribution adjustments, or use bootstrap methods with asymptotic refinements, such as the percentile-t or wild bootstrap, that can lead to improved finite sample inference.

  6. Heteroskedasticity-consistent standard errors - Wikipedia

    en.wikipedia.org/wiki/Heteroskedasticity...

    An alternative to explicitly modelling the heteroskedasticity is using a resampling method such as the wild bootstrap. Given that the studentized bootstrap, which standardizes the resampled statistic by its standard error, yields an asymptotic refinement, heteroskedasticity-robust standard errors remain nevertheless useful.

  7. Bessel's correction - Wikipedia

    en.wikipedia.org/wiki/Bessel's_correction

    Bessel's correction. In statistics, Bessel's correction is the use of n − 1 instead of n in the formula for the sample variance and sample standard deviation, [1] where n is the number of observations in a sample. This method corrects the bias in the estimation of the population variance. It also partially corrects the bias in the estimation ...

  8. Oversampling and undersampling in data analysis - Wikipedia

    en.wikipedia.org/wiki/Oversampling_and_under...

    Within statistics, oversampling and undersampling in data analysis are techniques used to adjust the class distribution of a data set (i.e. the ratio between the different classes/categories represented). These terms are used both in statistical sampling, survey design methodology and in machine learning . Oversampling and undersampling are ...

  9. Ratio estimator - Wikipedia

    en.wikipedia.org/wiki/Ratio_estimator

    Correction of the mean's bias. The correction methods, depending on the distributions of the x and y variates, differ in their efficiency making it difficult to recommend an overall best method. Because the estimates of r are biased a corrected version should be used in all subsequent calculations. A correction of the bias accurate to the first ...