Too little or too much R&D?

According to the first generation models of endogenous growth based on expanding product variety, the market economy unambiguously generates too little R&D. Later, by disentangling returns to specialization from the market power parameter, it was shown that with sufficiently low returns to specialization too much R&D can occur. The present paper takes a step further, disentangling the market power parameter from the capital share in final output. At a theoretical level this helps finding too much R&D as well. On the other hand, in view of the empirically realistic order of magnitude between the parameters, disentangling market power and capital share tends to diminish the scope for excess R&D. Finally, by differentiating between net and gross returns to specialization we demonstrate what drives the differing inefficiency results in this literature.