dplR (version 1.2.4)

series.rwl.plot: Compute Correlation between a Series and a Master Chronology

Description

Compute correlation between a tree-ring series and a master chronology by segment.

Usage

series.rwl.plot(rwl,series,series.yrs=as.numeric(names(series)),
  seg.length=100,bin.floor=100,n=NULL, prewhiten = TRUE, biweight=TRUE, ...)

Arguments

rwl

a data.frame with series as columns and years as rows such as that produced by read.rwl.

series

a numeric vector. Usually a tree-ring series.

series.yrs

a numeric vector giving the years of series. Defaults to as.numeric(names(series)).

seg.length

an even integer giving length of segments in years (e.g., 20, 50, 100 years).

bin.floor

a positive integer giving the base for locating the first segment (e.g.,.1600, 1700, 1800 AD). Typically 0, 10, 50, 100, etc.

n

NULL or an integer giving the filter length for the hanning filter used for removal of low frequency variation.

prewhiten

logical flag. If TRUE each series is whitened using ar.

biweight

logical flag. If TRUE then a robust mean is calculated using tbrm.

...

other arguments passed to plot.

Value

• A list containing the filtered vectors series and master.

Details

The function is typically invoked to produce a plot showing a time series plot of the series and the master as well as a scatterplot of series vs. master. The series and master are returned as well. Each series (inlcuding those in the rwl object) is optionally detrended as the residuals from a hanning filter with weight n. The filter is not applied if n is NULL. Detrending can also be done via prewhitening where the residuals of an ar model are added to each series mean. This is the default. The master chronology is computed as the mean of rwl object using tbrm if biweight=TRUE and rowMeans if not. Note that detrending can change the length of the series. E.g., a hanning filter will shorten the series on either end by floor(n/2). The effects of detrending can be seen with series.rwl.plot.

See Also

corr.rwl.seg corr.series.seg skel.plot ccf.series.rwl

Examples

data(co021)
  dat=co021
  flagged=dat$'646244'
  names(flagged)=rownames(dat)
  dat$'646107'=NULL
  foo=series.rwl.plot(rwl=dat,series=flagged,seg.length=100,n=5)
  #note effect of n on first year in the series
  foo=series.rwl.plot(rwl=dat,series=flagged,seg.length=100,n=13,prewhiten=FALSE)
  bar=series.rwl.plot(rwl=dat,series=flagged,seg.length=100,n=7,prewhiten=FALSE)
  head(foo$series)
  head(bar$series)