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Declusters a time series

Decluster.Rd

Identify cluster maxima above a threshold, using the runs method of Smith and Weissman (1994).

Usage

Decluster(Data, u = 0.95, Thres = NA, SepCrit = 3, mu = 365.25)

Arguments

Data

Numeric vector of the time series.

u

Numeric vector of length one specifying the declustering threshold; as a quantile [0,1] of Data vector. Default is 0.95.

Thres

Threshold expressed on the original scale of the observations. Only one of u and Thres should be supplied. Default is NA.

SepCrit

Integer; specifying the separation criterion under which events are declustered. Default is 3 corresponding to a storm window of three days in the case of daily data.

mu

(average) occurrence frequency of events in Data. Numeric vector of length one. Default is 365.25, daily data.

Value

List comprising the Threshold above which cluster maxima are identified, rate of cluster maxima Rate, a vector containing the original time series Detrended and the Declustered series.

See also

Detrend

Examples

#Declustering tailwater time series at structure S20
S20T_decl = Decluster(Data=S20_T_MAX_Daily_Completed_Detrend_Declustered$Detrend)
#Plotting detrended data
plot(as.Date(S20_T_MAX_Daily_Completed_Detrend_Declustered$Date),
    S20_T_MAX_Daily_Completed_Detrend_Declustered$Detrend,
    xlab="Date",ylab="Tailwater level (ft NGVD29)",pch=16,cex=0.5)
#Declustering threshold
abline(h=quantile(S20_T_MAX_Daily_Completed_Detrend_Declustered$Detrend,0.95), col="green")
#Cluster maxima
points(S20_T_MAX_Daily_Completed_Detrend_Declustered$Date[S20T_decl$EventsMax],
       S20_T_MAX_Daily_Completed_Detrend_Declustered$Detrend[S20T_decl$EventsMax],
       col="red",pch=16,cex=0.5)