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#42




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#44




Is it going to be offered then?
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#45




I think I have more study material than I need.
I got the new ASM manual and ADAPT exam questions, just found out that the ASM manual also has access to online practice questions. Has anyone here used the question bank from the ASM printed manuals? Same question bank right? I've only had acess to ADAPT for 5 days and I think it might be too late to ask for a partial refund. 
#46




Here's a question that I want to know how to calculate Var(Y) correctly using the inverse gamma if possible.
X follows a gamma distribution with parameters a=2.5 and theta=10 Y=(1/X) evaluate Var(Y) I did it and got 88.88888889 instead of .008888889 
#47




When you transform a variable, you also have to transform the scale parameter. If X has scale parameter theta = 10, then 1/X has scale parameter 1/10. I suspect you are still using 10 instead of 1/10.
To see why, if X is Gamma with theta = 10, then X = 10 * W, where W is Gamma with theta = 1. 1/W is inverse Gamma with theta =1. But 1/X = 1/(10W) = (1/10) * 1/W, so 1/X is inverse Gamma with theta = (1/10) * 1 = 1/10. 
#48




If X is Gamma with parameters alpha' and theta', then Y = 1 / X is Inverse Gamma with parameters alpha = alpha' and theta = 1 / theta'.
Here alpha' = 2.5 and theta' = 10 for the Gamma X, so alpha = 2.5 and theta = 1 / 10 = 0.1 for the Inverse Gamma Y. From the tables, E[Y^2] = (0.1)^2 / [(2.5  1) (2.5  2)] = 0.04 / 3, while E[Y] = (0.1) / (2.5  1) = 1 / 15. Then Var[Y] = (0.04 / 3)  (1 / 15)^2 = 0.00888... .
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Jim Daniel Jim Daniel's Actuarial Seminars www.actuarialseminars.com jimdaniel@actuarialseminars.com Last edited by Jim Daniel; 08102018 at 09:15 PM.. Reason: Typo 
#49




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#50




I am going over some of the ASM problems for chainladder and I really feel like they missed some details. I calculated loss reserves on problem 7.7 in the manual and when I compare my solution to the book's I see that they subtract 1 from one of the development factors. I don't know why because the reading doesn't say this, I'm guessing because it wasn't developed to 12/31 of the final CY, because it does this again in chain ladder problems that don't give a date. It has me frustrated right now.
Last edited by A Pimp Named Slickback; 08152018 at 05:44 PM.. 
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