GDP Forecast Of Shandong Province Based On Variable Selection And ARIMAX Model

GDP is a comprehensive core indicator of national accounts,and it also considered as the best indicator to measure the economic situation and development level of a country or region.It reflects the economic strength and market scale of a country or region.The economic development level of Shandong Province has been in the leading position in China,and its important feature is "stability".In recent years,it has occupied the third place in the GDP ranking list of all provinces in China.It is an economic province next to Guangdong and Jiangsu,which has a significant impact on the total national economy.However,since 2017,the GDP growth of Shandong Province has encountered many challenges,the downward pressure on the economy has increased,and the problems caused by the lack of vitality of economic growth in Shandong Province have further emerged,specifically,the difficulties in the development of the real economy,the slowdown in the growth of domestic demand,and the gap period for the transformation of new and old kinetic energy.In this context,it is of great signif icance to study and forecast the GDP of Shandong Province.At the same time,in view of the high degree of agreement between Shandong Province and the national macroeconomic policy,the research can also reflect the development trend of China's GDP and predict the overall economic trend of the country in the future.In this paper,we first select 11 socio-economic indicators related to GDP and macro-economic development through reference and relevant research,and use lasso method to select variables,excluding multiple collinearity among variables.After programming and calculation with R language,two indicators that have the most impact on the GDP development of Shandong Province are finally selected:the total output value of agriculture,forestry,animal husbandry and fishery and the total output value of industry.These two indicators analyze the current economic development status and some problems in Shandong Province.The first and the second industries have a significant impact on GDP.The third industry service industry,including commerce,finance,transportation and emerging industries,such as Internet industry,lacks development.The business level in Shandong Province needs greater development,the business environment needs to be further strengthened,and the entrepreneurship culture needs to be improved.The necessity and urgency of industrial upgrading and the transformation of new and old driving forces are urgent.Emerging industries need to be introduced and developed,and the ability of economic innovation needs to be strengthened.According to the national economic data in recent years,the scale of service industry is growing,the quality and efficiency are greatly improved,and new industries and new formats emerge in endlessly.At present,the service industry in Shandong Province needs further development,which can bring many new economic growth points,such as productive service industry,which has great potential in fine development;private fund raising of financial service industry,cultural tourism industry,Internet economic industry,such as big data,cloud computing,artificial intelligence,e-commerce,etc.At the same time,the development of service industry can also better improve and support the manufacturing industry and agriculture which are the main part of Shandong Province.In the face of the new economic situation and the impact of Sino US trade war,we should fully expand the excavation of domestic demand,constantly activate the development of small and micro enterprises of private enterprises,and create new economic growth points.Based on the selection of variables,SAS software is used to program and respond to these problems The ARIMA model is established for variables and explanatory variables respectively.At the same time,it forecasts itself according to the ARIMA model of response variables.After that,the ARIMAX model with input variables is established,and finally the GDP of Shandong Province is predicted.The prediction results show that ARIMAX model with input variables is more accurate than ARIMA model,and the prediction effect is more stable.