Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
Drexel University or The Math Forum.



Simulating number of occurrence Neg Binomial
Posted:
Apr 25, 2013 10:15 PM


Hi, I have a question regarding how to simulate the number of random occurrence for tornado outbreak.
Say if I have mean annual occurrence rate of 0.3, I can put that parameter in Poisson and simulate the number of outcome for 100k years. nSims = 100000; lambda=0.3; nOcc=poissrnd(lambda,[nSims, 1]); sum(nOcc)/nSims % close to input lambda
I read that I can also simulate the random number of occurrence using negative binomial. My question is what R parameter should be. Below I use 1, but clearly the average number is way too large compared to lambda. nOcc= nbinrnd( 1,lambda, nSims, 1); sum(nOcc)/nSims
ans = 2.3341 % on average we will see 2.3 Tornado per year?
Do I understand it correctly?



