logi.hist.plot2 {logihist}

Plot logistic regression

Description

Plot combined graphs for logistic regressions

Usage

logi.hist.plot2(independ, depend, logi.mod = 1, type = "dit", 
boxp = TRUE, rug = FALSE, ylabel = "Probability", ylabel2 = "Frequency", 
xlabel = "", mainlabel = "", las.h = 1, counts = FALSE, cex.p = 1, 
pch.dit = 1, incre = 0.02, ...)

Arguments

independ

explanatory variable

depend

dependent variable, typically a logical vector

logi.mod

type of fitting, 1 = logistic; 2 = "gaussian" logistic

type

type of representation, "dit" = dot plot; "hist" = histogram

boxp

TRUE = with box plots, FALSE = without

rug

TRUE = with rug plots, FALSE = without

ylabel

y-axis label

ylabel2

2nd y-axis label

xlabel

x-axix label

mainlabel

overall title for plot

las.h

orientation of axes labels (0 = vertical, 1 = horizontal

counts

add counts above histogram bars

cex.p

size of points in dotplots

pch.dit

Either an integer specifying a symbol or a single character to be used as the default in plotting points. See points for possible values and their interpretation.

incre

increment, i.e., separation between neighbour points in the dotplot.

...

additional options passed to logi.hist

Value

A combined logistic regression plot

Note

This is a new version of function logi.hist.plot already available in the package popbio. In this new version, control of points in the dot plot is provided by the arguments cex.p, pch.dit and incre.

Author(s)

M. de la Cruz Rot

References

De la Cruz Rot, M. 2005. Improving the Presentation of Results of Logistic Regression with R. ESA Bulletin 86:41-48.

Examples

data(aq.trans, package="popbio")

aq.trans$survived<-aq.trans$fate!="dead"

a<-subset(aq.trans, leaf<50 & stage!="recruit", c(leaf,survived))

logi.hist.plot2(a$leaf,  a$survived, 
type="hist", boxp=FALSE, counts=TRUE, int=10, 
ylabel="Survival probability", ylabel2="Number of plants", 
 xlab="Number of leaves" )

b<-glm(survived ~ leaf, binomial, data=a)
 summary(b)