Worsley.Likelihood.Ratio: Worsley's Likelihood Ratio test

Description Usage Arguments Value Author(s) Source References Examples

Description

WorsleyLikelihoodRatio returns the result of Worsley's Likelihood Ratio test applied to a time series.

Usage

1
WorsleyLikelihoodRatio(yearDF, datecol=1,valcol=2, returnZk=FALSE)

Arguments

yearDF

dataframe with climate data

datecol

column with dates

valcol

column with values

returnZk

return calculated data Zk

Value

The result of Worsley's Likelihood Ratio test.

Author(s)

Jose Gama

Source

Wijngaard, J. B., Klein Tank, A. M. G. and K<c3><b6>nnen, G. P. (2003), Homogeneity of 20th century European daily temperature and precipitation series. Int. J. Climatol., 23: 679<e2><80><93>692. doi: 10.1002/joc.906

References

Wijngaard, J. B., Klein Tank, A. M. G. and K<c3><b6>nnen, G. P. (2003), Homogeneity of 20th century European daily temperature and precipitation series. Int. J. Climatol., 23: 679<e2><80><93>692. doi: 10.1002/joc.906

Examples

1
demo(demoWorsleyLR)

Example output

	demo(demoWorsleyLR)
	---- ~~~~~~~~~~~~~

> # Worsley Likelihood Ratio 
> # example based on:
> # TREND Tests in Excel Spreadsheet
> # eWater toolkit TREND Version 1.0.2
> # http://www.toolkit.net.au/Tools/TREND/documentation
> 
> test1 <- matrix(c(1940,681,
+ 1941,3661,
+ 1942,8625,
+ 1943,2475,
+ 1944,573,
+ 1945,2794,
+ 1946,10190,
+ 1947,5143,
+ 1948,4139,
+ 1949,8945,
+ 1950,7295,
+ 1951,19883,
+ 1952,12119,
+ 1953,8772,
+ 1954,8848,
+ 1955,16309,
+ 1956,16254,
+ 1957,2303,
+ 1958,7671,
+ 1959,3985,
+ 1960,13742,
+ 1961,5333,
+ 1962,4859,
+ 1963,12381,
+ 1964,12137,
+ 1965,6075,
+ 1966,4669,
+ 1967,378,
+ 1968,7507,
+ 1969,3891,
+ 1970,13046,
+ 1971,12954,
+ 1972,2445,
+ 1973,14759,
+ 1974,20200,
+ 1975,16331,
+ 1976,6922,
+ 1977,6739,
+ 1978,11629,
+ 1979,7351,
+ 1980,2445,
+ 1981,9960,
+ 1982,10,
+ 1983,11786,
+ 1984,10214,
+ 1985,11216,
+ 1986,8393,
+ 1987,10005,
+ 1988,6896,
+ 1989,11632),ncol=2,byrow=TRUE)

> colnames(test1) <- c('year','data')

> WLR <- WorsleyLikelihoodRatio(test1,returnZk=TRUE)

> cat('Worsley Likelihood Ratio\n\nYear of change =',WLR$YearChange,'\nV =',WLR$V,'\nW =',WLR$W)
Worsley Likelihood Ratio

Year of change = 1945 
V = 0.3855236 
W = 2.894757
> plot(test1[,1], WLR$Zk ,type='l',xlab='',ylab='Worsley Likelihood Ratio')

climtrends documentation built on May 29, 2017, 11:58 p.m.