Abstrakt:
Mathematical models are used in many scientific researches not only in natural sciences but in social sciences. One of the basic demographic models is shown in this contribution - the mortality model. The reproduction of population is formed by two basic events - nativity and mortality. On base of survival function, the mortality intensity can be expressed as the quotient of probability density function and survival function. To estimate the mortality intensity for senior age (more 60 years) is difficult, the shape of trend function is following: I(t)=e(kt).c+z. The second problem, that was solved, is how to calculate the number of people living to certain age, when the mortality intensity is known. By the solution of differential equation we obtain the recipe ... The only problem is the shape of the function I(t). It could be difficult for senior age people. Slution for mortality intensity I(t) this category is shown in the contribution.