Extended Data Fig. 6: Posterior distribution function (PDF) for Bayesian Spectrum Analysis of annual change in biomass. | Nature Ecology & Evolution

Extended Data Fig. 6: Posterior distribution function (PDF) for Bayesian Spectrum Analysis of annual change in biomass.

From: Moth biomass increases and decreases over 50 years in Britain

Extended Data Fig. 6

Bayesian Spectrum Analysis was conducted on mean values for proportional biomass change across all traps in each year, with a prior probability distribution for frequency of cycles of 2–20 years. The density of the PDF at each value of years per cycle indicates the relative likelihood that the data represents a cycle with that frequency. The results indicate a high overall chance ( > 97.5%) of there being a pattern to biomass change that exceeds two years but low certainty of its exact period. This is consistent with the hypothesis that there are perturbations and ‘return times’ rather than ‘true’ periodicity in the data.

Back to article page