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#1001





#1003




have a stupid question for Meyers
Page 17. Table 6  Illustrative MCMC simulations I don't get why Betas in that table is between 0.5125 and 0.0518. These numbers do not follow the uniform distribution (5,5) in the model setup. What am I missing?
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#1004




I believe it's describing the prior distribution for the Bayesian methodology, which is your belief for where the values should belong before the posteriors are calculated. These are the "relatively wide prior distributions" it describes before listing the values. the method then homes in on the most likely values
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#1005




What the hell. For Mack 94, one of the chain ladder assumptions is that the variance of the expected losses is proportional to the cumulative losses to date.
Mack tests out 3 different selected LDF calculations: fk0 = C^2 weighted average LDF fk1 = C weighted average LDF (volume weighted LDF) fk2 = unweighted average LDF (simple average LDF) (C = cumulative losses) And then, states variance assumption behind each method: fk0 = Variance is proportional to 1 fk1 = Variance is proportional to C fk2 = Variance is proportional to C^2 Maybe I'm very dumb. But, I feel like the variance assumptions of fk0 and fk2 should be flipped to match how they are calculated?? Do you guys understand the logic behind this? 
#1006




Quote:
the residual equations are looking at the variance of the incremental, not the link ratio.
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Last edited by AbedNadir; 03172019 at 05:54 PM.. 
#1007




Quote:
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#1009




based on what I know about it, it's an iterative process where the parameters keep updating and shifting to maximize the likelihood of the posterior, so if your random data was produced from a normal distribution with mean 0 and sd 4 and then you gave it prior mean with range of 100150, and sd with prior 37, then if you run it enough then the mean will shift below the value of 100, the range is just to help with convergence of the posterior if you can give a close estimate
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#1010




Quote:

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brehm is my daddy, cfrf needs a forum, cs was here, firsttag, hi cs, mack 69 
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