Graduation - Mortality rate or force of mortality?

[Hanna Hohner]

Hello everyone!

I'm going through past papers on CT4 in order to practice graduation tests, but I've found that in all the past questions the mortality rates (q_x) are smoothed, and not the forces of mortality (mu_x). Also, there is a different formula for the standardised deviations than in the Core Reading (it looks like a binomial model, whereas in the Core Reading, the Poisson model is used by graduation). See for example question B6 in the 2006 April paper.

Can anyone explain to me what change exactly took place in the material regarding graduation, and to what extend I would find past papers useful in this topic?

Many thanks,
Hanna

 

[Andrew Martin]

Hello

The binomial model and graduating q_x are not in the Subject CS2 syllabus (nor is graphical graduation). That being said, there is crossover with the Poisson model and graduating mu_x. So some (not all) of these questions may be possible to do. For example, in question B6 of the 2006 April paper, you can still do the goodness-of-fit test as they have given you the standardised deviations (even though they are calculated with a different formula). Once you have the standardised deviations, the process is the same as if it were mu_x instead.

If you're familiar with the CS2 content, then you should be able to try and pick out what will be helpful for your revision. There are also past paper questions where it is mu being graduated. We also have questions relating to mu in our materials if you have these.

Hope this helps

Andy

 

[Hanna Hohner]

Thank you Andy, it was really helpful!