Autoregressive spatial smoothing and temporal spline smoothing for mappingrates

This article proposes generalized additive mixed models for the analysis of geographic and temporal variability of mortality rates. This class of mode ls accommodates random spatial effects and fixed and random temporal compon ents. Spatiotemporal models that use autoregressive local smoothing across the spatial dimension and B-spline smoothing over the temporal dimension ar e developed. The objective is the identification of temporal trends and the production of a series of smoothed maps from which spatial patterns of mor tality risks can be monitored over time. Regions with consistently high rat e estimates may be followed for further investigation. The methodology is i llustrated by analysis of British Columbia infant mortality data.