- Working on nonparametric-bayes.
Interesting PNAS comment from Doney & Sailley, (2013) (“When an ecological regime shift is really just stochastic noise”) on the Di Lorenzo & Ohman, (2013) piece in the same issue, showing that time integrated zooplankton data correlates closely with environmental drivers: in this case, the pacific decadal oscillation (PDO) index, which would be missed by the traditional approach of direct correlations. This refutes the previous explanation of such shifts observed in the krill populations as being driven by nonlinear ecological interactions, rather than merely linearly tracking the environment ((Hare & Mantua, 2000)). While there is some mention of how this may complicate traditional assumptions of warning signals, they do not remark on the obvious converse that the integral data may be more informative of detecting such shifts (whether or not they are tracking some abiotic dynamics).
In a related vein in the same issue is Liu et. al. (2013), discussing their algorithm for inferring complex dynamics from limited observations. Seems to do a poor job of putting the method into context of the suite of related approaches to addressing this problem (hidden Markov models, POMDP, etc), let alone directly comparing to them, which makes for a somewhat frustrating read. Still, could be a gem in the method I haven’t had a chance to dig into.
- From The Cover: A Double-Integration Hypothesis to Explain Ocean Ecosystem Response to Climate Forcing. E. Di Lorenzo, M. D. Ohman, (2013) Proceedings of The National Academy of Sciences 110 10.1073/pnas.1218022110
- When an Ecological Regime Shift is Really Just Stochastic Noise. S. C. Doney, S. F. Sailley, (2013) Proceedings of The National Academy of Sciences 110 10.1073/pnas.1222736110
- Observability of Complex Systems. Y.-Y. Liu, J.-J. Slotine, A.-L. Barabasi, (2013) Proceedings of The National Academy of Sciences 110 10.1073/pnas.1215508110
- Empirical Evidence For North Pacific Regime Shifts in 1977 And 1989. Steven R Hare, Nathan J Mantua, (2000) Progress in Oceanography 47 10.1016/S0079-6611(00)00033-1