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  2. Coefficient of determination - Wikipedia

    en.wikipedia.org/wiki/Coefficient_of_determination

    Ordinary least squares regression of Okun's law.Since the regression line does not miss any of the points by very much, the R 2 of the regression is relatively high.. In statistics, the coefficient of determination, denoted R 2 or r 2 and pronounced "R squared", is the proportion of the variation in the dependent variable that is predictable from the independent variable(s).

  3. Void coefficient - Wikipedia

    en.wikipedia.org/wiki/Void_coefficient

    A positive void coefficient means that the reactivity increases as the void content inside the reactor increases due to increased boiling or loss of coolant; for example, if the coolant acts predominantly as neutron absorber. This positive void coefficient causes a positive feedback loop, starting with the first occurrence of steam bubbles ...

  4. Total operating characteristic - Wikipedia

    en.wikipedia.org/wiki/Total_operating_characteristic

    where is the score for a positive instance and is the score for a negative instance, and and are probability densities as defined in previous section. It can further be shown that the AUC is closely related to the Mann–Whitney U , [ 7 ] [ 8 ] which tests whether positives are ranked higher than negatives.

  5. Receiver operating characteristic - Wikipedia

    en.wikipedia.org/wiki/Receiver_operating...

    A false positive in this case occurs when the person tests positive, but does not actually have the disease. A false negative, on the other hand, occurs when the person tests negative, suggesting they are healthy, when they actually do have the disease. Consider an experiment from P positive instances and N negative instances for some condition.

  6. Positive and negative predictive values - Wikipedia

    en.wikipedia.org/wiki/Positive_and_negative...

    The positive predictive value (PPV), or precision, is defined as = + = where a "true positive" is the event that the test makes a positive prediction, and the subject has a positive result under the gold standard, and a "false positive" is the event that the test makes a positive prediction, and the subject has a negative result under the gold standard.

  7. Regression validation - Wikipedia

    en.wikipedia.org/wiki/Regression_validation

    One measure of goodness of fit is the coefficient of determination, often denoted, R 2.In ordinary least squares with an intercept, it ranges between 0 and 1. However, an R 2 close to 1 does not guarantee that the model fits the data well.

  8. List of probability distributions - Wikipedia

    en.wikipedia.org/wiki/List_of_probability...

    The log-normal distribution, describing variables which can be modelled as the product of many small independent positive variables. The Lomax distribution; The Mittag-Leffler distribution; The Nakagami distribution; The Pareto distribution, or "power law" distribution, used in the analysis of financial data and critical behavior.

  9. Effect size - Wikipedia

    en.wikipedia.org/wiki/Effect_size

    In statistics, an effect size is a value measuring the strength of the relationship between two variables in a population, or a sample-based estimate of that quantity. It can refer to the value of a statistic calculated from a sample of data, the value of one parameter for a hypothetical population, or to the equation that operationalizes how statistics or parameters lead to the effect size ...