Suppose we are monitoring a volcano. Let 𝐸 be the event that there is an eruption in the next six months, and 𝑆 be the event that there is seismic activity (above some threshold). From experience and previous data, we have good reason to believe that:

Eruptions are rare with Pr(𝐸)=0.046.

Seismic activity almost always occurs when there is an imminent eruption, with Pr(π‘†βˆ£πΈ)=0.914.

Seismic activity occasionally occurs when there is no eruption imminent, with Pr(π‘†βˆ£πΈβˆ)=0.207.

Find the probability that an eruption will occur in the next six months, given current seismic activity (i.e. find Pr(πΈβˆ£π‘†)). You can either use the formula for Bayes rule directly, or you can use a hypothetical contingency table to help you.

Ensure your answer is accurate to 4 DP.

asked by guest
on Mar 13, 2025 at 12:20 am



Mathbot Says...

I wasn't able to parse your question, but the HE.NET team is hard at work making me smarter.


+ Submit Question