Page 114 - Contributed Paper Session (CPS) - Volume 8

CPS2210 Justyna Majewska et al.

In a two-population model, we expect certain behaviour from its
parameters. In a perfect situation the common parameters should be able to
capture the true global mortality trend, in both age and time, amongst the
populations as a whole (Enchev et al., 2015). If the underlying philosophy of
the model is correct, then we would expect that the country specific period
effects all fluctuate around some constant level in the long term (Enchev et al.,
2015). Significant differences from this level, in either range or shape would
mean that this particular population is somehow different from the other
populations.
Presented results are limited to the age-specific component, because
parameters α(x) for each pair of countries exhibit the same values and manifest
the expected general shape of mortality schedule across ages. Besides, almost
a similar downward trend is observed in the κ(t) values. Figures 3-6 present

values of estimated parameters β(x) for the independent LC model (each
country separetly) and for augmented common factor model. Parameter β(x)
reflects the relative change of mortality rate.

Fig. 3. Age-specific parameter bx for individual LC model fitted to pairs of male populations for
ages 0-100 (5-year age groups) and the period 1950-2015

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