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  2. Unbiased estimation of standard deviation - Wikipedia

    en.wikipedia.org/wiki/Unbiased_estimation_of...

    In statistics and in particular statistical theory, unbiased estimation of a standard deviation is the calculation from a statistical sample of an estimated value of the standard deviation (a measure of statistical dispersion) of a population of values, in such a way that the expected value of the calculation equals the true value.

  3. Standard deviation - Wikipedia

    en.wikipedia.org/wiki/Standard_deviation

    This defines a point P = (x 1, x 2, x 3) in R 3. Consider the line L = {(r, r, r) : r ∈ R}. This is the "main diagonal" going through the origin. If our three given values were all equal, then the standard deviation would be zero and P would lie on L. So it is not unreasonable to assume that the standard deviation is related to the distance ...

  4. Spot analysis - Wikipedia

    en.wikipedia.org/wiki/Spot_analysis

    Spot analysis, spot test analysis, or spot test is a chemical test, a simple and efficient technique where analytic assays are executed in only one, or a few drops, of a chemical solution, preferably in a great piece of filter paper, without using any sophisticated instrumentation.

  5. Statistical dispersion - Wikipedia

    en.wikipedia.org/wiki/Statistical_dispersion

    A measure of statistical dispersion is a nonnegative real number that is zero if all the data are the same and increases as the data become more diverse.. Most measures of dispersion have the same units as the quantity being measured.

  6. Robust measures of scale - Wikipedia

    en.wikipedia.org/wiki/Robust_measures_of_scale

    Robust measures of scale can be used as estimators of properties of the population, either for parameter estimation or as estimators of their own expected value.. For example, robust estimators of scale are used to estimate the population standard deviation, generally by multiplying by a scale factor to make it an unbiased consistent estimator; see scale parameter: estimation.

  7. Strictly standardized mean difference - Wikipedia

    en.wikipedia.org/wiki/Strictly_standardized_mean...

    For quality control, one index for the quality of an HTS assay is the magnitude of difference between a positive control and a negative reference in an assay plate. For hit selection, the size of effects of a compound (i.e., a small molecule or an siRNA) is represented by the magnitude of difference between the compound and a negative reference ...

  8. Best Buy broadly misses earnings estimates as consumers pull ...

    www.aol.com/finance/best-buy-expected-see...

    As of the market close on Monday, shares were up nearly 19% year to date, trailing behind the S&P 500's 25% gain. The earnings breakdown Here's what Best Buy posted for the third quarter, compared ...

  9. Bessel's correction - Wikipedia

    en.wikipedia.org/wiki/Bessel's_correction

    The sum of the entries in the last column (b 2) is the sum of squared distances between the measured sample mean and the correct population mean Every single row now consists of pairs of a 2 (biased, because the sample mean is used) and b 2 (correction of bias, because it takes the difference between the "real" population mean and the ...