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  2. Design effect - Wikipedia

    en.wikipedia.org/wiki/Design_effect

    This quantity reflects what would be the sample size that is needed to achieve the current variance of the estimator (for some parameter) with the existing design, if the sample design (and its relevant parameter estimator) were based on a simple random sample. [10] A related quantity is the effective sample size ratio, which can be calculated ...

  3. Completely randomized design - Wikipedia

    en.wikipedia.org/wiki/Completely_randomized_design

    The model for the response is , = + + with Y i,j being any observation for which X 1 = i (i and j denote the level of the factor and the replication within the level of the factor, respectively) μ (or mu) is the general location parameter; T i is the effect of having treatment level i

  4. Design matrix - Wikipedia

    en.wikipedia.org/wiki/Design_matrix

    The design matrix has dimension n-by-p, where n is the number of samples observed, and p is the number of variables measured in all samples. [4] [5]In this representation different rows typically represent different repetitions of an experiment, while columns represent different types of data (say, the results from particular probes).

  5. Surrogate model - Wikipedia

    en.wikipedia.org/wiki/Surrogate_model

    A surrogate model is an engineering method used when an outcome of interest cannot be easily measured or computed, so an approximate mathematical model of the outcome is used instead. Most engineering design problems require experiments and/or simulations to evaluate design objective and constraint functions as a function of design variables.

  6. Design of experiments - Wikipedia

    en.wikipedia.org/wiki/Design_of_experiments

    Design of experiments with full factorial design (left), response surface with second-degree polynomial (right) The design of experiments , also known as experiment design or experimental design , is the design of any task that aims to describe and explain the variation of information under conditions that are hypothesized to reflect the variation.

  7. Sampling (statistics) - Wikipedia

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

    Choice-based sampling or oversampling is one of the stratified sampling strategies. In choice-based sampling, [13] the data are stratified on the target and a sample is taken from each stratum so that rarer target classes will be more represented in the sample. The model is then built on this biased sample. The effects of the input variables on ...

  8. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    The sample size is an important feature of any empirical study in which the goal is to make inferences about a population from a sample. 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 ...

  9. Repeated measures design - Wikipedia

    en.wikipedia.org/wiki/Repeated_measures_design

    Repeated measures design is a research design that involves multiple measures of the same variable taken on the same or matched subjects either under different conditions or over two or more time periods. [1] For instance, repeated measurements are collected in a longitudinal study in which change over time is assessed.