Function returns the occurrence part of iETS model with the specified probability update and model types.
oes(y, model = "MNN", persistence = NULL, initial = "o",
initialSeason = NULL, phi = NULL, occurrence = c("fixed", "general",
"odds-ratio", "inverse-odds-ratio", "direct", "auto", "none"),
ic = c("AICc", "AIC", "BIC", "BICc"), h = 10, holdout = FALSE,
bounds = c("usual", "admissible", "none"), silent = c("all", "graph",
"legend", "output", "none"), xreg = NULL, regressors = c("use",
"select"), initialX = NULL, ...)
The object of class "occurrence" is returned. It contains following list of values:
model
- the type of the estimated ETS model;
timeElapsed
- the time elapsed for the construction of the model;
fitted
- the fitted values for the probability;
fittedModel
- the fitted values of the underlying ETS model, where applicable
(only for occurrence=c("o","i","d"));
forecast
- the forecast of the probability for h
observations ahead;
forecastModel
- the forecast of the underlying ETS model, where applicable
(only for occurrence=c("o","i","d"));
lower
- the lower bound of the interval if interval!="none"
;
upper
- the upper bound of the interval if interval!="none"
;
lowerModel
- the lower bound of the interval of the underlying ETS model
if interval!="none"
;
upperModel
- the upper bound of the interval of the underlying ETS model
if interval!="none"
;
states
- the values of the state vector;
logLik
- the log-likelihood value of the model;
nParam
- the number of parameters in the model (the matrix is returned);
residuals
- the residuals of the model;
y
- actual values of occurrence (zeros and ones).
persistence
- the vector of smoothing parameters;
phi
- the value of the damped trend parameter;
initial
- initial values of the state vector;
initialSeason
- the matrix of initials seasonal states;
occurrence
- the type of the occurrence model;
updateX
- boolean, defining, if the states of exogenous variables were
estimated as well.
initialX
- initial values for parameters of exogenous variables.
persistenceX
- persistence vector g for exogenous variables.
transitionX
- transition matrix F for exogenous variables.
accuracy
- The error measures for the forecast (in case of holdout=TRUE
).
B
- the vector of all the estimated parameters (in case of "odds-ratio",
"inverse-odds-ratio" and "direct" models).
The function estimates probability of demand occurrence, using the selected ETS state space models.
For the details about the model and its implementation, see the respective
vignette: vignette("oes","smooth")
Svetunkov, I., Boylan, J.E., 2023a. iETS: State Space Model for Intermittent Demand Forecastings. International Journal of Production Economics. 109013. tools:::Rd_expr_doi("10.1016/j.ijpe.2023.109013")
Teunter R., Syntetos A., Babai Z. (2011). Intermittent demand: Linking forecasting to inventory obsolescence. European Journal of Operational Research, 214, 606-615.
Croston, J. (1972) Forecasting and stock control for intermittent demands. Operational Research Quarterly, 23(3), 289-303.
adam, oesg, es
y <- rpois(100,0.1)
oes(y, occurrence="auto")
oes(y, occurrence="f")
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