chron: Build Mean Value Chronology
In dplR: Dendrochronology Program Library in R

Description Usage Arguments Details Value Author(s) References See Also Examples

This function builds a mean value chronology, typically from a data.frame of detrended ring widths as produced by detrend.

1	chron(x, prefix = "xxx", biweight = TRUE, prewhiten = FALSE, ...)

`x`	a `data.frame` of ring widths with `rownames(x)` containing years and `colnames(x)` containing each series ID such as produced by `read.rwl`
`prefix`	a `character` string with less than 4 characters. Defaults to `"xxx"`
`biweight`	`logical` flag. If TRUE then a robust mean is calculated using `tbrm.`
`prewhiten`	`logical` flag. If TRUE each series is whitened using `ar` prior to averaging.
`...`	Arguments passed to `ar` when `prewhiten` is `TRUE`. For example, use `aic` and `order.max` to control the order of the AR model.

This either averages the rows of the data.frame using a mean or a robust mean (the so-called standard chronology) or can do so from the residuals of an AR process (the residual chronology).

A data.frame with the standard chronology, residual chronology (if prewhitening was performed), and the sample depth.

Andy Bunn. Patched and improved by Mikko Korpela.

Cook, E. R. and Kairiukstis, L. A., editors (1990) Methods of Dendrochronology: Applications in the Environmental Sciences. Springer. ISBN-13: 978-0-7923-0586-6.

Fritts, H. C. (2001) Tree Rings and Climate. Blackburn. ISBN-13: 978-1-930665-39-2.

read.rwl, detrend, ar, crn.plot

library(graphics)
library(utils)
data(ca533)
ca533.rwi <- detrend(rwl = ca533, method = "ModNegExp")
ca533.crn <- chron(ca533.rwi, prefix = "CAM")
plot(ca533.crn,xlab="Year",ylab="RWI")
## With residual chron
ca533.crn <- chron(ca533.rwi, prefix = "CAM", prewhiten = TRUE)