Goodness-of-fit tests for parametric circular regression with spatial dependence: an application to wave direction modeling

This paper introduces goodness-of-fit tests for parametric circular regression models with spatially correlated errors, motivated by the analysis of wave direction data in the Adriatic Sea. The proposed methodology confronts a parametric model with a local linear kernel estimator that accounts for both the circular nature of the response and the spatial dependence in the observed field. Two test statistics are introduced: one based on the raw discrepancy between the parametric and nonparametric