Detecting Parameter Redundancy in Ecological State-Space Models Diana Cole and Rachel McCrea National Centre for Statistical Ecology, University of Kent
Lapwing Example
Symbolic Method for Detecting Parameter Redundancy
Parameter Redundancy in State-Space Models
Lapwing Example State-Space Model
Integrated Models
Lapwing Example State-Space Model Combined with Ring-Recovery Data
Extended Symbolic Method
Multi-Site Model McCrea et al (2010) consider a multi-site state-space model for great cormorants (Phalacrocorax carbo). Census data consisted of annual nest counts at 2 different sites (simplification of 3 sites). State-space model, where 1,k survival prob. of immature animals, 2,k survival prob. of breeders, ρ k productivity, k prob. becoming a breeder and kj transition prob. (site k). new born immature breeders
Multi-Site Model
Discussion Parameter redundancy of state-space models can be investigate by expanding the expectation of the observation process. It is not always necessary to combine state-space models with other types of data, even when not all states are observed. It is often possible to estimate more than expected. It is possible to investigate parameter redundancy in integrated models by combining exhaustive summaries for each data set. The reparameterisation theorem and extension theorem have been combined to create a simpler method to investigate parameter redundancy in integrated models.
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