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International Journal of
            Population Studies                                                  The use of multiregional life tables in Italy




                         A                                      B


























                  Figure 1. Regional and macroregional borders of Italy (A) and diagram of origin and destination of internal migration trajectories (B)
            and destination of migration flows (j) with j ≠ i. This is the   b T (y)
                                                                     ( ) =
            1  time that an Italian multiregional table has been built   ix b ey  ix j                     (I)
             st
                                                                    j
                                                                           b
            while taking into account the macroregion of birth.           ix . l (y)
              Once the rates were obtained, it was possible to apply        3  b T (y)
                                                                             = ix j
                                                                  b
                                                                   ey
            the passage formulas to measure the probability series   ix .  ( ) =   ∑ j1                    (II)
                                                                            b
            (death, emigration, and permanence). In our approach,           ix . l (y)
            consideration was also given to the probability of   To grasp the role played by age (x) in relation to
            emigrants dying if they remained in a mentioned territory   migration between macroregions, a measurement of
            ( p ).                                             “temporary life expectancy” (Arriaga, 1984) has been
             b
              i,i
              Clearly,  since  death  is  unavoidable,  the  matrix  of   constructed. This indicator represents the life expectancy
                                                               between two age groups and can be represented with the
            probabilities has been closed by making the probability of   following formula:
            death equal to 1 for the final open age class (70 and older
            years) and, of course, the remaining probabilities equal to   b e(x)  =  b  −T(x)  b  + T(x n)  (III)
            0 (emigration and permanence).                        i           b l( )x
              After these preliminary calculations, we calculated the   In this case, “n” is a generic number of years.
            survivors’ series (l), the deaths of the table (d), the total   The last three variables indicated represent the
            number of years (L) lived in the macroregion j (or k)   main measures on which the analyses proposed in this
            among the ages y and y+1 by individuals observed in the   contribution will focus.
            macroregion j (or k) at age y who lived in the macroregion
            i at age x applying Rogers’ (1973; 2015) formulas.   3. Results
            Therefore, “j” and “k” indicate two different macroregions   3.1. The survivorship history of the birth cohort
            of destination. The point (.) is used to signify that all the
            macroregions are jointly considered. This procedure,   The construction of the multiregional table has allowed us
            consistent with the traditional Rogers’ model (2015), has   to follow the survivorship and the migration history of four
            assured us greater confidence of the results.      birth cohorts in relation to the four Italian macroregions
                                                               (northwest, northeast, center, and south) from 2002 to
              Finally, after the calculation of the total number of   2013 (survivors and life expectancy by age, gender, and
            years lived (T) using Rogers’ (1973) approach, the life   macroregion of residence). As already stated, according
            expectancy (e) from the age y in the macroregion j of the   to international literature, the place-of-birth-dependent
            cohort formed in i at x age was obtained as follows:  approach  is  of  higher  accuracy.  This  approach  enables


            Volume 10 Issue 3 (2024)                        6                         https://doi.org/10.36922/ijps.1898
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