Specify p_spline method

Penalised splines is one of two optional Bayesian smoothing prior methods that can be selected and used in the model definition with EpiStrainDynamics. The main benefit of selecting the penalised spline method over random walks is that it can capture dynamical effects (fine enough temporal resolution) while not being too computationally expensive.

Usage

p_spline(spline_degree = 3, days_per_knot = 3)

Arguments

spline_degree

polynomial degree of the individual spline segments used to construct the overall curve (must be a positive whole number)

days_per_knot

number of days for each knot (must be a positive whole number)

Value

list with method and model parameters of class EpiStrainDynamics.method

See also

Other method: random_walk()

Examples

# Valid usage
p_spline(spline_degree = 2L, days_per_knot = 5L)
#> $method
#> [1] "p-spline"
#> 
#> $model_params
#> $model_params$spline_degree
#> [1] 2
#> 
#> $model_params$days_per_knot
#> [1] 5
#> 
#> 
#> attr(,"class")
#> [1] "EpiStrainDynamics.method"
p_spline(spline_degree = 3, days_per_knot = 7)
#> $method
#> [1] "p-spline"
#> 
#> $model_params
#> $model_params$spline_degree
#> [1] 3
#> 
#> $model_params$days_per_knot
#> [1] 7
#> 
#> 
#> attr(,"class")
#> [1] "EpiStrainDynamics.method"

# These will produce validation errors (as intended):
# \donttest{
# Non-positive values
try(p_spline(spline_degree = 0, days_per_knot = 5))
#> Error in validate_positive_whole_number(spline_degree, "spline_degree") : 
#>   Argument spline_degree must be a positive number
try(p_spline(spline_degree = 3, days_per_knot = -1))
#> Error in validate_positive_whole_number(days_per_knot, "days_per_knot") : 
#>   Argument days_per_knot must be a positive number

# Non-whole numbers
try(p_spline(spline_degree = 2.5, days_per_knot = 5))
#> Error in validate_positive_whole_number(spline_degree, "spline_degree") : 
#>   Argument spline_degree must be a whole number
try(p_spline(spline_degree = 3, days_per_knot = 4.2))
#> Error in validate_positive_whole_number(days_per_knot, "days_per_knot") : 
#>   Argument days_per_knot must be a whole number

# Non-numeric values
try(p_spline(spline_degree = "invalid", days_per_knot = 5))
#> Error in validate_positive_whole_number(spline_degree, "spline_degree") : 
#>   Argument spline_degree must be numeric
# }