Algorithms

SynHydro implements the following stochastic generation and disaggregation methods.

Generation Methods

Algorithm	Class	Type	Frequency	Sites
Thomas-Fiering AR(1)	ThomasFieringGenerator	Parametric	Monthly	Single
Kirsch Bootstrap	KirschGenerator	Nonparametric	Monthly	Multi
Matalas MAR(1)	MATALASGenerator	Parametric	Monthly	Multi
Phase Randomization	PhaseRandomizationGenerator	Nonparametric	Daily	Single
WARM	WARMGenerator	Parametric	Annual	Single
Multi-Site HMM	MultiSiteHMMGenerator	Parametric	Annual	Multi
ARFIMA	ARFIMAGenerator	Parametric	Monthly/Annual	Single
KNN Bootstrap	KNNBootstrapGenerator	Nonparametric	Monthly/Annual	Single/Multi
Gaussian/t-Copula	GaussianCopulaGenerator	Parametric	Monthly	Multi
Vine Copula	VineCopulaGenerator	Parametric	Monthly	Multi

Disaggregation Methods

Algorithm	Class	Type	Frequency
Nowak KNN	NowakDisaggregator	Nonparametric	Monthly-to-Daily
Valencia-Schaake	ValenciaSchaakeDisaggregator	Parametric	Annual-to-Monthly
Grygier-Stedinger	GrygierStedingerDisaggregator	Parametric	Annual-to-Monthly

Key Properties Preserved

Property	Thomas-Fiering	Kirsch	Matalas	Phase Random	WARM	HMM	ARFIMA	KNN Bootstrap	Copula	Vine Copula
Monthly means/stds	x	x	x	-	-	-	x	x	x	x
Temporal correlation	x	x	x	x	x	x	x	x	x	x
Spatial correlation	-	x	x	-	-	x	-	x	x	x
Long-range persistence	-	-	-	-	x	-	x	-	-	-
Non-stationarity	-	-	-	-	x	-	-	-	-	-
Drought states	-	-	-	-	-	x	-	-	-	-
Power spectrum	-	-	-	x	x	-	x	-	-	-
Empirical distribution	-	x	-	-	-	-	-	x	x	x
Tail dependence	-	-	-	-	-	-	-	-	x (t-copula)	x (asymmetric)