psych (version 1.0-17)

error.crosses: Plot x and y error bars

Description

Given two vectors of data, plot the means and show standard errors in both X and Y directions.

Usage

error.crosses(x, y, labels = NULL, pos = NULL, arrow.len = 0.2, ...)

Arguments

x

A vector of summary statistics (from Describe)

y

A second vector of summary statistics (also from Describe)

labels

name the pair

pos

Labels are located where with respect to the mean?

arrow.len

Arrow length

...

Other parameters for plot

Details

For an example of two way error bars describing the effects of mood manipulations upon positive and negative affect, see http://personality-project.org/revelle/publications/happy-sad-appendix/FIG.A-6.pdf)

Examples

#desc <- describe(attitude)
#x <- desc[1,]
#y <- desc[2,]
#plot(x$mean,y$mean)   #in graphics window
#error.crosses(x,y)    #in graphics window

## The function is currently defined as

function (x,y,labels=NULL,pos=NULL,arrow.len=.2,...)  # x  and y are data frame with 
    {z <- dim(x)[1]
     if (length(pos)==0) {locate <- rep(1,z)} else {locate <- pos}
     if (length(labels)==0) lab <- rep("",z) else lab <-labels
        for (i in 1:z)  
    	{xcen <- x$mean[i]
    	 ycen <- y$mean[i]
    	 xse  <- x$se[i]
    	 yse <-  y$se[i]
    	 arrows(xcen-xse,ycen,xcen+xse,ycen,length=arrow.len, angle = 90,
    	 code=3,col = par("fg"), lty = NULL, lwd = par("lwd"), xpd = NULL)
    	 arrows(xcen,ycen-yse,xcen,ycen+yse,length=arrow.len, angle = 90,
    	 code=3,col = par("fg"), lty = NULL, lwd = par("lwd"), xpd = NULL)
    	text(xcen,ycen,labels=lab[i],pos=pos[i],cex=1,offset=arrow.len+1) 
    	#puts in labels for all points
    	}	
   }