An Empirical Study On The Impact Of Population Age Structure On Economic Growth In Hefei City

In recent years,the city of Hefei has experienced rapid economic development and has been successfully ranked among the new first-tier cities.The rapid economic development is accompanied by a series of population age structure problems such as deepening aging.On the one hand,economic development has attracted more and more young talents to work;on the other hand,the influx of excessive labor has changed the age structure of the population.In the context of national macro-regulation of fertility policy,this paper analyzes the current situation of population and economy in Hefei,understands the influence of different age structures on economic development and proposes countermeasures in response to the research results to continuously improve the positive effect of population on economy.The research content is as follows:(1)The regression analysis of population age structure indicators and external indicators on the level of savings and the level of science and technology innovation,which indirectly affect the economy,is conducted.Firstly,a ridge regression model is established to eliminate the effect of multiple cointegration for the savings level;a random forest model(RF)is established to rank the importance of the influencing factors and explore the magnitude of the influence of each influencing factor on the savings level.The fitting accuracy of the models is compared and it is found that the random forest has the highest fitting accuracy.Second,for STI level,the effect of population age structure on STI level is obtained using principal component analysis to eliminate the effect of multicollinearity.It is found that the juvenile dependency ratio is negatively related to the savings rate but the increase in the elderly dependency ratio has a positive effect on the savings rate;the working-age population share and the elderly population share have a significant positive effect on the STI level and contribute to the improvement of the STI level.(2)To explore the direct impact of population age structure on economic development through time series analysis.A VAR model was built to conduct impulse response analysis to explore the direct impact of population age structure on economic growth.The ARIMA model is constructed for forecasting,and improved on this basis by introducing a random forest model to extract nonlinear influences and constructing a combined ARIMA-RF model.It is found that the working-age population share and total dependency ratio act directly on the level of economic development and contribute to it;the prediction effect of the combined ARIMA-RF model is better than that of the VAR or ARIMA models.Considering that the old-age dependency ratio has a certain role in promoting the level of savings,the level of science and technology innovation and economic development,this paper proposes countermeasures and suggestions that are conducive to the coordinated development of population and economy in Hefei from three aspects:improving the efficiency of labor force utilization and science and technology innovation capacity,developing the elderly power resources through flexible retirement and developing the aging industry to cope with aging.