Posts Tagged ‘ likelihood ’

Maximum likelihood estimates for multivariate distributions

September 22, 2012
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Maximum likelihood estimates for multivariate distributions

Consider our loss-ALAE dataset, and - as in Frees & Valdez (1998) - let us fit a parametric model, in order to price a reinsurance treaty. The dataset is the following, > library(evd) > data(lossalae) > Z=lossalae > X=Z;Y=Z ...

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Inference and autoregressive processes

September 6, 2012
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Inference and autoregressive processes

Consider a (stationary) autoregressive process, say of order 2,for some white noise with variance . Here is a code to generate such a process, > phi1=.5 > phi2=-.4 > sigma=1.5 > set.seed(1) > n=240 > WN=rnorm(n,sd=sigma) > ...

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MAT8886 a short word on profile likelihood

February 7, 2012
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MAT8886 a short word on profile likelihood

Profile likelihood is an interesting theory to visualize and compute confidence interval for estimators (see e.g. Venzon & Moolgavkar (1988)). As we will use is, we will plotBut more generally, it is possible to considerwhere . Then (...

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Hey! I made you some Wiener processes!

September 7, 2011
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Hey! I made you some Wiener processes!

Check them out. Here are thirty homoskedastic ones: > homo.wiener for (j in 1:30) {  for (i in 2:length(homo.wiener)) {          homo.wiener for (j in 1:30) {        plot( homo.wiener,           type = "l", col = rgb(.1,....

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The truncated Poisson

February 21, 2010
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The truncated Poisson

A common model for counts data is the Poisson. There are cases however that we only record positive counts, ie there is a truncation of 0. This is the truncated Poisson model. To study this model we only need the total counts and the sample size. This comes from the sufficient statistic principle as the

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