linReg: linear regression with plotting

In berryFunctions: Function Collection Related to Plotting and Hydrology

linear regression with plotting

Description

uses lm; plots data if add=FALSE, draws the regression line with abline and writes the formula with legend

Usage

linReg(
  x,
  y = NULL,
  data = NULL,
  add = FALSE,
  digits = 2,
  quiet = FALSE,
  pch = 16,
  col = "black",
  colline = "red",
  colband = addAlpha(colline),
  level = 0.95,
  plotrange = par("usr")[1:2],
  lwd = 1,
  xlab = deparse(substitute(x)),
  ylab = deparse(substitute(y)),
  main = "linear regression",
  pos1 = "top",
  pos2 = NULL,
  inset = 0,
  legargs = NULL,
  ...
)

Arguments

x	Numeric or formula (see examples). Vector with values of explanatory variable
y	Numeric. Vector with values of dependent variable. DEFAULT: NULL
data	Dataframe. If x is a formula, the according columns from data are used as x and y. DEFAULT: NULL
add	Logical. If TRUE, line and text are added to the existing graphic. DEFAULT: FALSE (plots datapoints first and then the line.)
digits	Numeric vector of length \ge 1. Specifies number of digits a,b,r,e are rounded to in the formula "y=a*x+b \n R^2=r \n RMSE=e", respectively. If a value is negative, the complete respective entry is left away. If values are not specified, they are set equal to the first. DEFAULT: 2
quiet	Silence NA-removal warnings in rmse? DEFAULT: FALSE
pch	Point Character of datapoints, see par. DEFAULT: 16
col	Color of points. DEFAULT: "black"
colline	Color of the regression line, see par. DEFAULT: "red"
colband	Color of the confidence region band. DEFAULT: addAlpha(col)
level	Confidence level, see predict.lm. DEFAULT: 0.95
plotrange	x range for which regression line and uncertainty band should be plotted. Is passed to seqR and can hence be a vector. DEFAULT: par("usr")[1:2]
lwd	Numeric. Linewidth, see par. DEFAULT: 1
xlab	Axis label if add=FALSE. DEFAULT: deparse(substitute(x))
ylab	Axis label if add=FALSE. DEFAULT: deparse(substitute(y))
main	Title if add=FALSE. Changed (if not specified) for x=formula with data. DEFAULT: "linear regression"
pos1	xy.coords-acceptable position of the formula. DEFAULT: "top"
pos2	For numerical coordinates, this is the y-position. DEFAULT: NULL, as in legend
inset	Numeric vector of length \le 2. inset distance(s) from the margins as a fraction of the plot region when formula legend is placed by keyword. DEFAULT: 0
legargs	list of arguments passed to legend, like list(cex=0.8, xpd=TRUE, bg="white"), ... xpd specifies whether formula can be written only inside the plot region (when FALSE) or inside the figure region including mar (when TRUE) or in the entire device region including oma (when NA). DEFAULT: NULL
...	Further arguments passed to plot

Value

None, used for plotting and drawing.

Author(s)

Berry Boessenkool, [e-mail], 2011-2012, 2015

See Also

lm, mReg, expReg, legend, par, abline.

Examples

a <- 1:30
b <- a/2.345+rnorm(30,0,3)

linReg(a,b)
linReg(a,b, ylab="Hallo", pch=1, colline=3, main="Regression by Berry")
linReg(a, b, pos1=15, pos2=0) # position of topleft corner of legend
linReg(a, b, pos1=NA) # to suppress legend
linReg(a, b, plotrange=5:20) # only for plotting, all data points are used!
linReg(a,b, digits=c(2,3,2,-1) ) # Do not write RMSE into legend

# Formula specification:
linReg(b~a)
linReg(Fertility~Education, data=swiss, col="blue", colline="green")
# col is for points, colline + colband for regression line + conf.int.

# For more flexibility with the datapoints, plot first, then use linReg with add=TRUE:
plot(a,b, xlim=c(-5,45))
linReg(a, b, pos1="bottomright", add=TRUE, inset=.1) # inset: distance from plot border
linReg(a, b, digits=c(7,4,3), add=TRUE, colline=3, lty=2, lwd=4, level=0.8)
linReg(a, b, pos1="topleft", inset=c(-0.1, 0.3), legargs=list(xpd=TRUE), add=TRUE)

berryFunctions documentation built on May 29, 2024, 4:01 a.m.