Effects of Model Formulation on Estimates of Health in Individual Right Whales (Eubalaena glacialis)
Right whales are vulnerable to many sources of anthropogenic disturbance including ship strikes, entanglement with fishing gear, and anthropogenic noise. The effect of these factors on individual health is unclear. A statistical model using photographic evidence of health was recently built to infer the true or hidden health of individual right whales. However, two important prior assumptions about the role of missing data and unexplained variance on the estimates were not previously assessed. Here we tested these factors by varying prior assumptions and model formulation. We found sensitivity to each assumption and used the output to make guidelines on future model formulation.
KeywordsMissing data Body condition Process error Bayesian Photo identification
This work was supported by Office of Naval Research Grants N00014-10-1-0516 and N00014-12-1-0286 to Duke University and the University of St. Andrews. This work benefited from discussions with participants in a working group supported by Office of Naval Research Grants N00014-09-1-0896 to the University of California, Santa Barbara, and N00014-12-1-0274 to the University of California, Davis.
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