This discussion paper resulted in a publication in the <I>Journal of Economic Dynamics and Control</I> (2013), 37(12), 2729-2754.<P> Existing models of R&D are not easily reconciled with four observable aspects of R&D: initial technologies ('ideas') need to be developed further, only a minority of initial...</p></i>

In this paper, we consider deterministic (both fluid and discrete) polling systems with N queues with infinite buffers and we show how to compute the best polling sequence (minimizing the average total workload). With two queues, the best polling sequence is always periodic when the system is...

This paper derives and estimates rules for fiscal policy that prescribe the optimal response to changes in unemployment and debt. We combine the reduced form model of the economy from a linear VAR with a non-linear welfare function and obtain analytic solutions for optimal policy. The variables...