Semi-endogenous or fully endogenous growth? A unified theory
提出一个统一理论，将半内生和完全内生增长机制结合，分析长期增长率的决定因素，并给出判断半内生增长是否必要的标准，对增长经济学研究者有参考价值。
Is growth ultimately fully endogenous or semi-endogenous? Three decades of theoretical and empirical growth economics have kept both possibilities open. Here, R & D-driven growth is a general combination of both semi-endogenous and fully endogenous mechanisms. I demonstrate that if the semi-endogenous growth component is indispensable to the actual growth mechanism, the long-run growth rate follows the semi-endogenous growth predictions. Conversely, if the semi-endogenous growth is non-essential and the world population experiences slow growth, the fully endogenous growth mechanism could dictate the long run, even if it is not essential. If no other (third) growth mechanism exists, a criterion sufficient to ascertain the essentiality of semi-endogenous growth is that reduced research consistently leads to fewer innovations. If an unknown third growth engine exists, the steady state remains semi-endogenous, provided the essentiality criterion is met. Regardless of how this third factor impacts short-term growth, semi-endogenous growth will prevail in the long run.