Research on investment efficiency evaluation of mining industry in Africa based on super-efficiency DEA model

The African continent is an important mineral resource acquisition site for the our country's “go global” strategies and “the Belt and Road” initiative.A large number of Chinese mining companies have invested in Africa for more than two decades.How efficient is our country's mining investment in Africa in recent years.The authors use the super-efficiency DEA method to select 9 countries including Democratic Republic of the Congo and South Africa to conduct empirical research on our country's mining input-output data in these countries in 2014 and 2020 to reflect the efficiency data difference and trend of change of our country's mining investment in Africa.The results show that our country's mining industry investment in Africa is regionally unbalanced, and investment in minerals is too concentrated.The investment efficiency of most countries is at medium and low levels and the difference in investment efficiency is large.The overall investment efficiency is converging and the investment scale is shrinking.Therefore, it proposes to optimize investment areas, adjust investment minerals, expand investment scale, improve investment efficiency, seize opportunities in the investment adjustment period under the influence of the COVID-19, while maintaining stability and other suggestions.