Stability of Growth Models with Generalised Lag Structures

This paper considers the lag structures of dynamic models in economics, arguing that the standard approach is too simple to capture the complexity of actual lag structures arising, for example, from pro- duction and investment decisions. It is argued that recent (1990s) developments in the the theory of functional di¤erential equations provide a means to analyse models with generalised lag structures. The stability and asymptotic stability of two growth models with gen- eralised lag structures are analysed. The paper’s penultimate section includes a speculative discussion of time-varying parameters.