Question

In 70 years there have been 13 pandemics. Using this information and Poisson distribution, calculate how long until there is a 90% probability of another pandemic.

Find the average number of pandemics/year.

What formula is used to find the number of years until there is a 90% chance of another worldwide pandemic?

What is the number of years?

Answer 1

a) The average number of pandemics per year is computed here as:

= 13/70

= 0.1857

Therefore 0.1857 is the required number of pandemics/year here.

b) The waiting time for a pandemic could be modelled here as:

The probability of having a pandemic in the next t years is obtained here as:

This should be equal to 0.9.

Therefore, we have here:

Therefore 12.40 years is the required number of years here.