# What is the False Negative Rate?

The False Negative Rate (Miss Rate) is a performance metric that measures the probability that your model will predict *negative *when the true value is *positive*.

- It is closely related to the False Positive Rate, which is completely analogous.
- The True Positive Rate and the False Negative Rate sum up to 1.
- The False Negative Rate is the answer to the following question:
**“If the true value is positive, what share did my model predict incorrectly?”** - The False Negative Rate is calculated as follows: