ABSTRACT
This chapter reviews the ideas of "chaotic" dynamics, and their possible applications to economics. It presents a very brief survey of nonlinear dynamics and possible applications to economics. The chapter discusses how to extract ergodic parameters from time series. It focuses on the delicate problem of predictions. The chapter shows that economists try to make time evolutions more manageable by "detrending". It is quite clear that aperiodic time evolutions may arise and do arise in several rather different manners. Free trade introduces a coupling between the different national economics which will tend to introduce nontrivial time dependence, possibly with sensitive dependence on the initial condition. Quantitative help appears also possible in the analysis of time series which are sufficiently long and accurate. The most desirable thing to extract from the study of time series in economics and finance is a reliable prediction of the future.
