公共投資と経済成長

フィスカル•ポリシイと資源配分

抄録

The purposes of this paper are to build a new model of economic growth of mixed economy in which public investment exists and a new attempt for appreciations of three paths to full employment growth in view of efficiency of resource allocation.
The main assumptions are as follows:
1° Output capacity Q is a Cobb=Dougras function of social overhead capital Kp, private capital K, labor L and state of technique, i. e., Q=beμtKαpKβLγ.
2° Private investment I is determined by Kp, K and interest rate γ.
3° Public investment Ip increases total demand and Kp.
4° Government realizes full employment growth by the control of (a) Ip or (b) fiscal parameters which change saving ratio s (tax rate and public consumption rate) or (c) γ.
5° Complete competition in labor market.
The analysis is described in terms of output-private capital ratio x=Y/X and capital ratio y=K/Kp. The patterns of growth paths depend seriously on the policy which government uses and sign (α+β-1).
In this paper, the optimum capital ratio xop means the long-run equilibrium capital ratio β/α which maximizes discount sum of total consumption under any given constant saving ratio, and the optimum saving ratio sop means the saving ratio α+β which maximizes total consumption level approximately, and the conditions of long-run efficiency, i. e., x=xop and s=sop are studied.
Lastly, the growth path which is attained if government has accomplishment of given constant capital ratio as an object and its efficiency in view of fiscal policy are analized briefly.