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Tail Probability and Survival Function

Tail probabilities capture exceedance risk and are central to reliability, anomalies, and statistical testing.

Try This In The Plotter

Jump directly into the tail risk workflow and apply this guide on a live distribution chart.

Open Interactive Tail Risk

What Is Tail Probability?

Tail probability asks how likely values are beyond a threshold, such as P(X > x).

Right tails quantify high-end risk, and left tails quantify low-end extremes.

Survival Function

The survival function is S(x) = 1 − F(x).

It is a direct way to read exceedance probabilities and often easier than subtracting CDF values manually.

Where It Matters

Tail metrics appear in quality control, reliability engineering, fraud detection, and hypothesis tests.

Log-scale survival plots are especially useful for rare-event comparison.