Draws bars relevant to breakpoint estimates (point estimate and confidence limits) on the current device
# S3 method for segmented
lines(x, term, bottom = TRUE, shift=FALSE, conf.level = 0.95, k = 50,
pch = 18, rev.sgn = FALSE, .vcov=NULL, .coef=NULL, ...)
an object of class segmented
.
the segmented variable of the breakpoints being drawn. It may be unspecified when there is a single segmented variable.
logical, indicating if the bars should be plotted at the bottom (TRUE
) or at the top (FALSE
).
logical, indicating if the bars should be `shifted' on the y-axis before plotting. Useful for multiple breakpoints with overlapped confidence intervals.
the confidence level of the confidence intervals for the breakpoints.
a positive integer regulating the vertical position of the drawn bars. See Details.
either an integer specifying a symbol or a single character to be used
in plotting the point estimates of the breakpoints. See points
.
should the signs of the breakpoint estimates be changed before plotting? see Details.
The full covariance matrix of estimates. If unspecified (i.e. NULL
), the covariance matrix is computed internally by vcov(x)
.
The regression parameter estimates. If unspecified (i.e. NULL
), it is computed internally by coef(x)
.
further arguments passed to arrows
, for instance `col' that
can be a vector.
lines.segmented
simply draws on the current device the point estimates and relevant
confidence limits of the estimated breakpoints from a "segmented" object. The y coordinate
where the bars are drawn is computed as usr[3]+h
if bottom=TRUE
or
usr[4]-h
when bottom=FALSE
, where h=(usr[4]-usr[3])/abs(k)
and
usr
are the extremes of the user coordinates of the plotting region.
Therefore for larger values of k
the bars are plotted on the edges.
The argument rev.sgn
allows to change the sign of the breakpoints before plotting. This may
be useful when a null-right-slope constraint is set.
plot.segmented
to plot the fitted segmented lines, and
points.segmented
to add the fitted joinpoints.