On a comparison between the effects of productivity and survival rate on national population

The national population is increased by the improvements in industrial productivity and/or survival rate. This paper compares the effects of these two causes using a mathematical model. The increases in the populations of the age-groups are described by a system of linear recurrence relations whose coefficients consist of those parameters such as productivity per capita and survival rate. So far as the values of these parameters remain small, the age group populations, and hence, the total population converge to their limit values, which are regarded as the final state of the national population. It is estimated numerically that the effect of the unit of percentage change in survival rate on this final population is equivalent to 1.5 times of that in productivity. Moreover, it is observed that this estimation is almost independent of the values of parameters in approximate terms. [In Japanese.]