4 Default ageprior

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4.1 Default

The default ageprior used during parentage assignment is flat and minimally informative: it only specifies that parent and offspring cannot have an age difference of 0 (\(\alpha_{A,R}=0\) for \(A=0\) and \(R=M\) or \(R=P\), black in Figure 4.1) and that all other age / relationship combinations are allowed (\(\alpha_{A,R}=1\), pale green).

MakeAgePrior(LifeHistData = LH_HSg5)

## Ageprior: Flat 0/1, overlapping generations, MaxAgeParent = 6,6

Figure 4.1: Default minimally informative ageprior

##   M P FS MS PS
## 0 0 0  1  1  1
## 1 1 1  1  1  1
## 2 1 1  1  1  1
## 3 1 1  1  1  1
## 4 1 1  1  1  1
## 5 1 1  1  1  1
## 6 1 1  0  0  0
## 7 0 0  0  0  0

The range of possible age differences is taken from LifeHistData:

table(LH_HSg5$BirthYear)

## 
## 2000 2001 2002 2003 2004 2005 
##   40  192  192  192  192  192

The maximum age of parents MaxAgeParent is initially set to the maximum age difference possible among individuals in LifeHistData (here 2005-2000 = 5 years) \(+1\). This ensures that all pairs are age-wise considered as potential siblings ¹; the age difference between siblings can never be larger than MaxAgeParent \(-1\).

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1. Up to version 2.0, initial MaxAgeParent was set to diff(BYrange), but sibling relationships were also allowed at this age difference, so this change (probably) won’t affect parentage assignment or full pedigree reconstruction.↩︎