Sensitivity and Specificity

Sensitivity And Specificity

Sensitivity and specificity are statistical measures of the performance of a binary classification test, also known in statistics as classification function. Sensitivity (also called the true positive rate, or the recall rate in some fields) measures the proportion of actual positives which are correctly identified as such (e.g. the percentage of sick people who are correctly identified as having the condition). Specificity measures the proportion of negatives which are correctly identified as such (e.g. the percentage of healthy people who are correctly identified as not having the condition, sometimes called the true negative rate). These two measures are closely related to the concepts of type I and type II errors. A perfect predictor would be described as 100% sensitive (i.e. predicting all people from the sick group as sick) and 100% specific (i.e. not predicting anyone from the healthy group as sick); however, theoretically any predictor will possess a minimum error bound known as the Bayes error rate.

For any test, there is usually a trade-off between the measures. For example: in an airport security setting in which one is testing for potential threats to safety, scanners may be set to trigger on low-risk items like belt buckles and keys (low specificity), in order to reduce the risk of missing objects that do pose a threat to the aircraft and those aboard (high sensitivity). This trade-off can be represented graphically as a receiver operating characteristic curve.

Read more about Sensitivity And Specificity:  Definitions, Medical Examples, Worked Example, Estimation of Errors in Quoted Sensitivity or Specificity, Terminology in Information Retrieval, See Also

Other articles related to "sensitivity and specificity, sensitivity, specificity":

Sensitivity And Specificity - See Also
... with miss, Type II error sensitivity or true positive rate (TPR) eqv ... with false alarm rate, fall-out accuracy (ACC) specificity (SPC) or True Negative Rate positive predictive value (PPV) eqv ... Matthews correlation coefficient Receiver operating characteristic or ROC curve Selectivity Sensitivity index Statistical significance Youden's J statistic OpenEpi software ...
Computer-aided Diagnosis Topics - Sensitivity and Specificity
... The hit rate (sensitivity) can be up to 90% depending on system and application ... The less FPs indicated, the higher the specificity is ... A low specificity reduces the acceptance of the CAD system because the user has to identify all of these wrong hits ...

Famous quotes containing the words sensitivity and and/or sensitivity:

    The vanity of men, a constant insult to women, is also the ground for the implicit feminine claim of superior sensitivity and morality.
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    The sensitivity of men to small matters, and their indifference to great ones, indicates a strange inversion.
    Blaise Pascal (1623–1662)