Create a covariance parameter object for us with other functions.
See spmodel::randcov_params() for documentation regarding
random effect covariance parameter objects.
Usage
tailup_params(tailup_type, de, range)
taildown_params(taildown_type, de, range)
euclid_params(euclid_type, de, range, rotate, scale)
nugget_params(nugget_type, nugget)Arguments
- tailup_type
The tailup covariance function type. Available options include
"linear","spherical","exponential","mariah","epa", and"none".- de
The spatially dependent (correlated) random error variance. Commonly referred to as a partial sill.
- range
The correlation parameter.
- taildown_type
The taildown covariance function type. Available options include
"linear","spherical","exponential","mariah","epa", and"none".- euclid_type
The euclidean covariance function type. Available options include
"spherical","exponential","gaussian","cosine","cubic","pentaspherical","wave","jbessel","gravity","rquad","magnetic", and"none".- rotate
Anisotropy rotation parameter (from 0 to \(\pi\) radians) for the euclidean portion of the covariance. A value of 0 (the default) implies no rotation.
- scale
Anisotropy scale parameter (from 0 to 1) for the euclidean portion of the covariance. A value of 1 (the default) implies no scaling.
- nugget_type
The nugget covariance function type. Available options include
"nugget"or"none".- nugget
The spatially independent (not correlated) random error variance. Commonly referred to as a nugget.
References
Peterson, E.E. and Ver Hoef, J.M. (2010) A mixed-model moving-average approach to geostatistical modeling in stream networks. Ecology 91(3), 644–651.
Ver Hoef, J.M. and Peterson, E.E. (2010) A moving average approach for spatial statistical models of stream networks (with discussion). Journal of the American Statistical Association 105, 6–18. DOI: 10.1198/jasa.2009.ap08248. Rejoinder pgs. 22–24.
Examples
tailup_params("exponential", de = 1, range = 20)
#> de range
#> 1 20
#> attr(,"class")
#> [1] "tailup_exponential"
taildown_params("exponential", de = 1, range = 20)
#> de range
#> 1 20
#> attr(,"class")
#> [1] "taildown_exponential"
euclid_params("exponential", de = 1, range = 20, rotate = 0, scale = 1)
#> de range rotate scale
#> 1 20 0 1
#> attr(,"class")
#> [1] "euclid_exponential"
nugget_params("nugget", nugget = 1)
#> nugget
#> 1
#> attr(,"class")
#> [1] "nugget_nugget"