If the values of Precision and recall are the same then what are the reasons behind that similarity. Also, I want to know what is precision and recall tradeoff and when it occurred?
These indicators are in a contradiction - the higher the value of Sensitivity (Recall), the lower the value of Specificity (Precision) and vice versa. In order to optimize algorithm, sometimes use F-measure (
F = 2/(1/precision + 1/recall) ) or the breakeven point (point, where precision = recall).