Question

What is true postive,true negative,false positive anf false negative?

Answer 1

Sensitivity (also called the true positive rate, the recall, or probability of detection in some fields) measures the proportion of positives that are correctly identified as such (e.g. the percentage of sick people who are correctly identified as having the condition).
A true negative test result is one that does not detect the condition when the condition is absent. Definition 3. A false positive test result is one that detects the condition when the condition is absent