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  2. Accuracy and precision - Wikipedia

    en.wikipedia.org/wiki/Accuracy_and_precision

    In the language of statistics: Accuracy is a description of systematic errors, a measure of bias. Precision is a description of random errors, a measure of variability. In the context of observations made on a ratio or interval scale, a statistical sample can be said to be accurate if its average is close to the true value of the quantity being ...

  3. Precision and recall - Wikipedia

    en.wikipedia.org/wiki/Precision_and_recall

    To calculate the recall for a given class, we divide the number of true positives by the prevalence of this class (number of times that the class occurs in the data sample). The class-wise precision and recall values can then be combined into an overall multi-class evaluation score, e.g., using the macro F1 metric .

  4. Precision (statistics) - Wikipedia

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

    Precision (statistics) For broader coverage of this topic, see Accuracy and precision. In statistics, the precision matrix or concentration matrix is the matrix inverse of the covariance matrix or dispersion matrix, . [1] [2] [3] For univariate distributions, the precision matrix degenerates into a scalar precision, defined as the reciprocal of ...

  5. F-score - Wikipedia

    en.wikipedia.org/wiki/F-score

    F-score. In statistical analysis of binary classification and information retrieval systems, the F-score or F-measure is a measure of predictive performance. It is calculated from the precision and recall of the test, where the precision is the number of true positive results divided by the number of all samples predicted to be positive ...

  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. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    Sample size determination or estimation is the act of choosing the number of observations or replicates to include in a statistical sample. 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 ...

  8. Confidence interval - Wikipedia

    en.wikipedia.org/wiki/Confidence_interval

    Informally, in frequentist statistics, a confidence interval ( CI) is an interval which is expected to typically contain the parameter being estimated. More specifically, given a confidence level (95% and 99% are typical values), a CI is a random interval which contains the parameter being estimated % of the time. [ 1][ 2] The confidence level ...

  9. Estimation statistics - Wikipedia

    en.wikipedia.org/wiki/Estimation_statistics

    Estimation statistics, or simply estimation, is a data analysis framework that uses a combination of effect sizes, confidence intervals, precision planning, and meta-analysis to plan experiments, analyze data and interpret results. [ 1] It complements hypothesis testing approaches such as null hypothesis significance testing (NHST), by going ...