Hertog, R. den

innovation market firm size intensity industry structure audretsch result small-firm r &d intensity coefficient difference capital intensity market structure concentration growth small-firm innovation rate variable influence labour value determinant market growth capital product innovation rate economic market structure variables profitability small-firm innovation research business measure production value market concentration number ratio activity level study market structure determinants production model approach paper effect evidence four-firm concentration ratio r &d intensities r &d activities table r &d employment stage employment small-firm r &d entry opportunity regression rothwell change manufacturing dutch journal profit employee kleinknecht netherland power university barrier labour costs time periods growth stages entry favour innovation market structure data market structure characteristics schumpeterian hypothesis project dodgson ex-post market power