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  2. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    The table shown on the right can be used in a two-sample t-test to estimate the sample sizes of an experimental group and a control group that are of equal size, that is, the total number of individuals in the trial is twice that of the number given, and the desired significance level is 0.05. [4]

  3. Probability-proportional-to-size sampling - Wikipedia

    en.wikipedia.org/wiki/Probability-proportional...

    [4]: 250 So, for example, if we have 3 clusters with 10, 20 and 30 units each, then the chance of selecting the first cluster will be 1/6, the second would be 1/3, and the third cluster will be 1/2. The pps sampling results in a fixed sample size n (as opposed to Poisson sampling which is similar but results in a random sample size with ...

  4. Bernoulli sampling - Wikipedia

    en.wikipedia.org/wiki/Bernoulli_sampling

    Scaled f(k, n, 0.2) for four values of n. A percentage of 20%, say, is usually expressed as a probability p=0.2. In that case, random variates are generated in the unit interval. After running the algorithm, a sample of size k will have been selected.

  5. Sampling (statistics) - Wikipedia

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

    Steps for using sample size tables: Postulate the effect size of interest, α, and β. Check sample size table [20] Select the table corresponding to the selected α; Locate the row corresponding to the desired power; Locate the column corresponding to the estimated effect size. The intersection of the column and row is the minimum sample size ...

  6. Random walk - Wikipedia

    en.wikipedia.org/wiki/Random_walk

    A Wiener process is the scaling limit of random walk in dimension 1. This means that if there is a random walk with very small steps, there is an approximation to a Wiener process (and, less accurately, to Brownian motion). To be more precise, if the step size is ε, one needs to take a walk of length L/ε 2 to approximate a Wiener length of L ...

  7. Systematic sampling - Wikipedia

    en.wikipedia.org/wiki/Systematic_sampling

    We then generate a random start from a uniform distribution between 0 and 1, and move along the number line in steps of 1. Example: We have a population of 5 units (A to E). We want to give unit A a 20% probability of selection, unit B a 40% probability, and so on up to unit E (100%).

  8. Sampling distribution - Wikipedia

    en.wikipedia.org/wiki/Sampling_distribution

    In statistics, a sampling distribution or finite-sample distribution is the probability distribution of a given random-sample-based statistic.If an arbitrarily large number of samples, each involving multiple observations (data points), were separately used in order to compute one value of a statistic (such as, for example, the sample mean or sample variance) for each sample, then the sampling ...

  9. Simple random sample - Wikipedia

    en.wikipedia.org/wiki/Simple_random_sample

    It is a process of selecting a sample in a random way. In SRS, each subset of k individuals has the same probability of being chosen for the sample as any other subset of k individuals. [ 1 ] Simple random sampling is a basic type of sampling and can be a component of other more complex sampling methods.