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  2. Kaplan–Meier estimator - Wikipedia

    en.wikipedia.org/wiki/Kaplan–Meier_estimator

    The Kaplan–Meier estimator, [1][2] also known as the product limit estimator, is a non-parametric statistic used to estimate the survival function from lifetime data. In medical research, it is often used to measure the fraction of patients living for a certain amount of time after treatment. In other fields, Kaplan–Meier estimators may be ...

  3. Interpolation - Wikipedia

    en.wikipedia.org/wiki/Interpolation

    In the mathematical field of numerical analysis, interpolation is a type of estimation, a method of constructing (finding) new data points based on the range of a discrete set of known data points. [1][2] In engineering and science, one often has a number of data points, obtained by sampling or experimentation, which represent the values of a ...

  4. Central limit theorem - Wikipedia

    en.wikipedia.org/wiki/Central_limit_theorem

    The scaled sum of a sequence of i.i.d. random variables with finite positive variance converges in distribution to the normal distribution. In probability theory, the central limit theorem (CLT) states that, under appropriate conditions, the distribution of a normalized version of the sample mean converges to a standard normal distribution.

  5. Instrumental variables estimation - Wikipedia

    en.wikipedia.org/wiki/Instrumental_variables...

    In statistics, econometrics, epidemiology and related disciplines, the method of instrumental variables (IV) is used to estimate causal relationships when controlled experiments are not feasible or when a treatment is not successfully delivered to every unit in a randomized experiment. [1]

  6. Bias of an estimator - Wikipedia

    en.wikipedia.org/wiki/Bias_of_an_estimator

    In statistics, the bias of an estimator (or bias function) is the difference between this estimator 's expected value and the true value of the parameter being estimated. An estimator or decision rule with zero bias is called unbiased. In statistics, "bias" is an objective property of an estimator. Bias is a distinct concept from consistency ...

  7. Calibration curve - Wikipedia

    en.wikipedia.org/wiki/Calibration_curve

    A calibration curve plot showing limit of detection (LOD), limit of quantification (LOQ), dynamic range, and limit of linearity (LOL).. In analytical chemistry, a calibration curve, also known as a standard curve, is a general method for determining the concentration of a substance in an unknown sample by comparing the unknown to a set of standard samples of known concentration. [1]

  8. x̅ and s chart - Wikipedia

    en.wikipedia.org/wiki/X̅_and_s_chart

    Use variable-width control limits [6] Each observation plots against its own control limits as determined by the sample size-specific values, n i, of A 3, B 3, and B 4: Use control limits based on an average sample size [7] Control limits are fixed at the modal (or most common) sample size-specific value of A 3, B 3, and B 4

  9. Maximum likelihood estimation - Wikipedia

    en.wikipedia.org/wiki/Maximum_likelihood_estimation

    Maximum likelihood estimation. In statistics, maximum likelihood estimation (MLE) is a method of estimating the parameters of an assumed probability distribution, given some observed data. This is achieved by maximizing a likelihood function so that, under the assumed statistical model, the observed data is most probable.