Wolff, P. de

tinbergen change income production policy theory development investment order model problem economic distribution investment goods price welfare cycle planning country result market research economist equation period wolff business labor income distribution measurement phenomena economy relation value labour netherland dutch continuity amsterdam volume study increase experience world consumer nation system choice analysis science method factor unemployment physics business cycles coefficient integration employment product number respect trade keyne example calculation difference institution demand synthesis testing industry depreciation labour market labor productivity approach bureau subject professor tinbergen university element