Animal spirits and the composition of innovation in a lab-equipment R&D model with transition

We study the effect of animal spirits on the composition of aggregate R&D, the consumption level and economic growth in a tournament model of horizontal and vertical R&D. By considering a full lab-equipment specification, the model predicts a positive effect of animal spirits on the balanced-growth-path (BGP) level of per-capita consumption without impacting on economic growth and on aggregate vertical R&D. However, transition is slower under “waves of enthusiasm”, implying a longer period in which growth rates are higher than the BGP level. An economy that is subject to expectations shocks then converges at a time-varying speed. On average over time, transition is longer but less “painful”—i.e., with higher per-capita consumption levels—than otherwise.