# What is the False Discovery Rate?

Given a *positive *prediction, the **False Discovery Rate **(FDR) is the performance metric that tells you the probability that the true value is *negative*.

- It is closely related to the False Omission Rate, which is completely analogous.
- The complement of the False Discovery Rate is the Positive Predictive Value. Consequently, they add up to 1.
- The False Discovery Rate answers the question:
**“If the prediction is positive, what share of my prediction is truly negative?”** - The False Discovery Rate is calculated as follows:

\frac{FP}{TP+FP} = \frac{FP}{P} = FDR