Of Thresholds, Invasions, and Regime Shifts

Ecological thresholds and regime shifts: approaches to identification.

There is an apparent gap between the prominence of present theoretical frameworks involving ecological thresholds and regime shifts, and the paucity of efforts to conduct simple tests and quantitative inferences on the actual appearance of such phenomena in ecological data. A wide range of statistical methods and analytical techniques are now available that render these questions tractable, som...

The Characteristics of Epid Invasions with Thresholds

In this paper we report the development of a ing the principal characteristics (velocity, lead sions or epidemics described by determinis whose dynamics include a threshold or Allee e the correct results for single-component mode and then demonstrate by numerical experimen class of epidemic and invasion models includ Rosenzweig McArthur predator prey model. consider the atto fox effect in the c...

Regime Shifts and Volatility Spillovers

A standard capital asset pricing model is extended to allow for stochastic shifts in the volatility of the news process. This model is then estimated on bivariate stock market data to separate two exogenous news processes – a world and a domestic. The results indicate that the influence of the world news process on the Swedish stock market has increased significantly over the period 1970-1995. ...

Macroeconomic Regimes and Regime Shifts

Red noise and regime shifts

The analysis of interdecadal physical and biological variability is made challenging by the relative shortness of available time series. It has been suggested that rapid temporal changes of the most energetic empirical orthogonal function of North Pacific sea surface temperature (sometimes called the Pacific Decadal Oscillation or PDO) represents a ‘‘regime shift’’ between states with otherwise...