The principle of permissible intervals and extreme challenges in adjustment for macroeconomic systems

The article substantiates the fruitfulness of the application of the principle of permissible intervals for the study of dynamics of macroeconomic systems. On the basis of achievements of predecessors, the authors trace the cognitive trend, in which the formulation and solution of traditional extreme problems associated with the optimization of the values of key macroparameters becomes insufficient — this is only the first step to identify the range of acceptable, sustainable values of those parameters. The application of the principle of permissible intervals is illustrated by the example of such a key indicator as the annual inflation rate for the Russian economy for the period 2001–2018. Based on the regression analysis of time series, middle-run trends are constructed, expressing the functional relationship between the annual rate of inflation and some macroeconomic parameters. Comparing the obtained extreme points, we come to the fact that the permissible values of the annual rate of inflation should be maintained, tend to lie in the range of 7,38% and 16,10%. In addition, studying the middle-run dependencies between the inflation rate and annual GDP increments found by the method of moving intervals, we combine the extreme points of the middle-run trends into one dynamic series and find a long-run envelope of those trends. In conclusion, the connection of the principle of permissible intervals with the tasks of ensuring the stability and security of economic systems is discussed, the advantages of this principle in comparison with the traditional optimization problems are shown, and the directions of further research in this area are outlined.