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  2. Heckman correction - Wikipedia

    en.wikipedia.org/wiki/Heckman_correction

    The Heckman correction is a statistical technique to correct bias from non-randomly selected samples or otherwise incidentally truncated dependent variables, a pervasive issue in quantitative social sciences when using observational data. [1]

  3. Observational error - Wikipedia

    en.wikipedia.org/wiki/Observational_error

    Systematic errors are errors that are not determined by chance but are introduced by repeatable processes inherent to the system. [5] Sources of systematic errors include errors in equipment calibration, uncertainty in correction terms applied during experimental analysis, errors due the use of approximate theoretical models.

  4. Randomized controlled trial - Wikipedia

    en.wikipedia.org/wiki/Randomized_controlled_trial

    Regardless of the statistical methods used, important considerations in the analysis of RCT data include: Whether an RCT should be stopped early due to interim results. For example, RCTs may be stopped early if an intervention produces "larger than expected benefit or harm", or if "investigators find evidence of no important difference between ...

  5. Jackknife resampling - Wikipedia

    en.wikipedia.org/wiki/Jackknife_resampling

    The jackknife pre-dates other common resampling methods such as the bootstrap. Given a sample of size n {\displaystyle n} , a jackknife estimator can be built by aggregating the parameter estimates from each subsample of size ( n − 1 ) {\displaystyle (n-1)} obtained by omitting one observation.

  6. Stepped-wedge trial - Wikipedia

    en.wikipedia.org/wiki/Stepped-wedge_trial

    An RCT is a scientific experiment that is designed to reduce bias when testing a new medical treatment, a social intervention, or another testable hypothesis. In a traditional RCT, the researcher randomly divides the experiment participants into two groups at the same time: One group receives the treatment (the "treatment group")

  7. Blocking (statistics) - Wikipedia

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

    However, the different methods share the same purpose: to control variability introduced by specific factors that could influence the outcome of an experiment. The roots of blocking originated from the statistician, Ronald Fisher , following his development of ANOVA .

  8. Approximation error - Wikipedia

    en.wikipedia.org/wiki/Approximation_error

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  9. Experimental uncertainty analysis - Wikipedia

    en.wikipedia.org/wiki/Experimental_uncertainty...

    Implicitly, all the analysis has been for the Method 2 approach, taking one measurement (e.g., of T) at a time, and processing it through Eq(2) to obtain an estimate of g. To use the various equations developed above, values are needed for the mean and variance of the several parameters that appear in those equations.