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  2. Stratified sampling - Wikipedia

    en.wikipedia.org/wiki/Stratified_sampling

    Proportionate allocation uses a sampling fraction in each of the strata that are proportional to that of the total population. For instance, if the population consists of n total individuals, m of which are male and f female (and where m + f = n), then the relative size of the two samples (x 1 = m/n males, x 2 = f/n females) should reflect this proportion.

  3. Neyman allocation - Wikipedia

    en.wikipedia.org/wiki/Neyman_allocation

    Neyman allocation, also known as optimum allocation, is a method of sample size allocation in stratified sampling developed by Jerzy Neyman in 1934. This technique determines the optimal sample size for each stratum to minimize the variance of the estimated population parameter for a fixed total sample size and cost.

  4. Stratified randomization - Wikipedia

    en.wikipedia.org/wiki/Stratified_randomization

    Graphic breakdown of stratified random sampling. In statistics, stratified randomization is a method of sampling which first stratifies the whole study population into subgroups with same attributes or characteristics, known as strata, then followed by simple random sampling from the stratified groups, where each element within the same subgroup are selected unbiasedly during any stage of the ...

  5. Sampling (statistics) - Wikipedia

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

    Accidental sampling (sometimes known as grab, convenience or opportunity sampling) is a type of nonprobability sampling which involves the sample being drawn from that part of the population which is close to hand. That is, a population is selected because it is readily available and convenient.

  6. Stratification (clinical trials) - Wikipedia

    en.wikipedia.org/wiki/Stratification_(clinical...

    Proportionate stratified sampling involves selecting participants from each stratum in proportions that match the general population. [1] This method can be used to improve the sample's representation of the population, by ensuring that characteristics (and their proportions) of the study sample reflect the characteristics of the population.

  7. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    In practice, the sample size used in a study is usually determined based on the cost, time, or convenience of collecting the data, and the need for it to offer sufficient statistical power. In complex studies, different sample sizes may be allocated, such as in stratified surveys or experimental designs with multiple treatment groups.

  8. List of analyses of categorical data - Wikipedia

    en.wikipedia.org/wiki/List_of_analyses_of...

    Aickin's α; Andres and Marzo's delta; Bangdiwala's B; Bennett, Alpert, and Goldstein’s S; Brennan and Prediger’s κ; Coefficient of colligation - Yule's Y; Coefficient of consistency

  9. Balanced repeated replication - Wikipedia

    en.wikipedia.org/wiki/Balanced_repeated_replication

    Consider first an idealized situation, where each stratum of our sample contains only two units. Then each half-sample will contain exactly one of these, so that the half-samples share the stratification of the full sample. If there are s strata, we would ideally take all 2 s ways of choosing the half-stratum; but if s is large, this may be ...