lag.plot {stats}

R Documentation

Time Series Lag Plots

Description

Plot time series against lagged versions of themselves. Helps visualizing ‘auto-dependence’ even when auto-correlations vanish.

Usage

lag.plot(x, lags = 1, layout = NULL, set.lags = 1:lags,
         main = NULL, asp = 1,
         diag = TRUE, diag.col = "gray", type = "p", oma = NULL,
         ask = NULL, do.lines = (n <= 150), labels = do.lines,
         ...)

Arguments

x	time-series (univariate or multivariate)
lags	number of lag plots desired, see arg set.lags.
layout	the layout of multiple plots, basically the mfrow par() argument. The default uses about a square layout (see n2mfrow such that all plots are on one page.
set.lags	vector of positive integers allowing specification of the set of lags used; defaults to 1:lags.
main	character with a main header title to be done on the top of each page.
asp	Aspect ratio to be fixed, see plot.default.
diag	logical indicating if the x=y diagonal should be drawn.
diag.col	color to be used for the diagonal if(diag).
type	plot type to be used, but see plot.ts about its restricted meaning.
oma	outer margins, see par.
ask	logical or NULL; if true, the user is asked to confirm before a new page is started.
do.lines	logical indicating if lines should be drawn.
labels	logical indicating if labels should be used.
...	Further arguments to plot.ts. Several graphical parameters are set in this function and so cannot be changed: these include xlab, ylab, mgp, col.lab and font.lab: this also applies to the arguments xy.labels and xy.lines.

Details

If just one plot is produced, this is a conventional plot. If more than one plot is to be produced, par(mfrow) and several other graphics parameters will be set, so it is not (easily) possible to mix such lag plots with other plots on the same page.

If ask = NULL, par(ask = TRUE) will be called if more than one page of plots is to be produced and the device is interactive.

Note

It is more flexible and has different default behaviour than the S version. We use main = instead of head = for internal consistency.

Author(s)

Martin Maechler

See Also

plot.ts which is the basic work horse.

Examples

require(graphics)

lag.plot(nhtemp, 8, diag.col = "forest green")
lag.plot(nhtemp, 5, main="Average Temperatures in New Haven")
## ask defaults to TRUE when we have more than one page:
lag.plot(nhtemp, 6, layout = c(2,1), asp = NA,
         main = "New Haven Temperatures", col.main = "blue")

## Multivariate (but non-stationary! ...)
lag.plot(freeny.x, lags = 3)
## Not run: 
no lines for long series :
lag.plot(sqrt(sunspots), set = c(1:4, 9:12), pch = ".", col = "gold")

## End(Not run)

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