Physical Sciences and Mathematics Commons^™

Spatial Models To Account For Variation In Observer Effort In Bird Atlases, Andrew M. Wilson, Daniel W. Brauning, Caitlin Carey, Robert S. Mulvihill

Environmental Studies Faculty Publications

To assess the importance of variation in observer effort between and within bird atlas projects and demonstrate the use of relatively simple conditional autoregressive (CAR) models for analyzing grid-based atlas data with varying effort. Pennsylvania and West Virginia, United States of America. We used varying proportions of randomly selected training data to assess whether variations in observer effort can be accounted for using CAR models and whether such models would still be useful for atlases with incomplete data. We then evaluated whether the application of these models influenced our assessment of distribution change between two atlas projects separated by twenty …