I am having difficulty (and my textbook is of no help!) figuring out when to treat a problem as a linear death process with death parameters $\mu n$h vs. a pure death process with death parameter $\mu$h. Is there anything we need to look out for in questions to signify which one to use? Thanks for the help!
Differentiate between linear death process and pure death process
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2 Answers
Think of it this way. Given there are n individuals alive now, approximately how many do you expect to die in the next $\Delta t$ of time? If different individuals' deaths are independent (which is the typical situation when the individuals are people or animals), this should be proportional to $n$ - there are more deaths per day in a big city than there are in a small village. So then you want $\mu n \Delta t$. On the other hand, you could have cases where the expected number of deaths does not depend on $n$. For example, you might imagine a situation where deaths in an animal population occur only because at random times a hunter will come along and shoot one member of the population. The hunter will not shoot more when there are more animals. So in this case you would use $\mu \Delta t$.
But, i think a death process with death parameter $\mu_n$ is called pure death process and a death process with death parameter $\mu$ will poisson death process?
Where $\mu n$ is linear death process?