[R] Plot binomial regression line

[Uwe Ligges]

On 26.05.2011 10:45, Jörgen Svan wrote:
> Dear all,
>
> I am quite new with R and I have a problem with plotting a binomial
> regression line in a plot.
>
> This is what I type in:
>> model<-glm(Para~Size,binomial)
>> par(mfrow=c(1,1))
>> xv<-seq(3.2,4.5,0.01)
>> yv<-predict(model,list(area=xv),type="response")
>> plot(Size,Para)
>> lines(xv,yv)

Several things I'd improve, hence the whole code:

dat <- read.table("clipboard", header=TRUE)
dat$Para <- factor(dat$Para)
model <- glm(Para ~ Size, data=dat, family="binomial")
xv <- seq(3.2,4.5,0.01)
yv <- predict(model, newdata=data.frame(Size=xv), type="response")
with(dat, plot(Size, as.integer(Para)-1))
lines(xv, yv)

Best,
Uwe Ligges



> The error message that I get is:
>
>> Error in xy.coords(x, y) : 'x' and 'y' lengths differ
>
> My txt-file is attached. Could someone please help me to find out what I did
> wrong.
>
> Thank you on beforehand,
> Jörgen
>
>
> PerBinom.txt
>
>
> Para	Size
> 1	4.464285714
> 1	4.196428571
> 1	4.151785714
> 1	4.151785714
> 1	3.973214286
> 1	4.285714286
> 1	4.0625
> 1	4.241071429
> 1	4.0625
> 1	4.017857143
> 1	4.0625
> 1	4.017857143
> 1	4.241071429
> 1	4.151785714
> 1	4.0625
> 1	4.285714286
> 1	4.196428571
> 1	4.107142857
> 1	4.0625
> 1	4.330357143
> 1	4.375
> 1	4.196428571
> 1	4.196428571
> 1	3.928571429
> 1	4.0625
> 1	4.0625
> 1	4.107142857
> 1	4.196428571
> 1	3.928571429
> 1	4.151785714
> 1	3.705357143
> 1	3.75
> 1	4.107142857
> 1	3.839285714
> 1	3.616071429
> 1	4.0625
> 1	3.75
> 1	4.017857143
> 1	3.571428571
> 1	4.151785714
> 1	3.883928571
> 1	3.705357143
> 1	4.017857143
> 1	4.0625
> 1	4.0625
> 1	4.196428571
> 1	3.839285714
> 1	4.107142857
> 1	4.017857143
> 1	3.839285714
> 1	3.526785714
> 1	4.196428571
> 1	4.017857143
> 1	3.883928571
> 1	4.0625
> 1	4.107142857
> 1	4.285714286
> 1	3.928571429
> 1	3.794642857
> 1	4.107142857
> 1	4.107142857
> 1	3.839285714
> 1	4.241071429
> 1	4.285714286
> 1	4.375
> 0	4.115044248
> 0	3.495575221
> 0	4.203539823
> 0	3.982300885
> 0	4.026548673
> 0	4.07079646
> 0	3.805309735
> 0	4.07079646
> 0	3.982300885
> 0	4.247787611
> 0	4.203539823
> 0	3.982300885
> 0	3.849557522
> 0	4.115044248
> 0	3.849557522
> 0	4.07079646
> 0	4.203539823
> 0	3.849557522
> 0	4.247787611
> 0	4.026548673
> 0	4.07079646
> 0	4.203539823
> 0	4.026548673
> 0	3.982300885
> 0	4.026548673
> 0	3.584070796
> 0	4.026548673
> 0	3.982300885
> 0	3.761061947
> 0	3.230088496
> 0	3.495575221
> 0	3.982300885
> 0	3.938053097
> 0	3.849557522
> 0	3.982300885
> 0	3.849557522
> 0	4.026548673
> 0	3.938053097
> 0	4.159292035
> 0	3.849557522
> 0	4.026548673
> 0	3.672566372
> 0	4.159292035
> 0	3.761061947
> 0	4.247787611
> 0	4.115044248
> 0	3.539823009
> 0	3.89380531
> 0	4.115044248
> 0	3.849557522
> 0	4.115044248
> 0	4.115044248
> 0	4.07079646
> 0	3.584070796
> 0	3.407079646
> 0	4.203539823
>
>
>
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