R help - Apr 2006 - Dotplot x-axis

Here's a small dataset:

type <-
c('hierarchical','partial','single','complete','single
+hierarchical','single+partial','partial+hierarchical','single+partial
+hierarchical')
freq <- c(1455,729,688,65,29,28,16,17)
lodds <- log(freq/(3027 - freq))
dotplot(type~lodds)

I would like to have the x-axis have ticks at nice, close to equally- 
spaced values, of the proportions rather than at round log-odds  
values, which appear as -5:0. For example: perhaps have ticks at c 
(0.007, 0.02, 0.05, 0.12, 0.27, 0.5), which are approximate values of  
exp(-5:0)/(1+exp(-5:0))

Advice?
_____________________________
Professor Michael Kubovy
University of Virginia
Department of Psychology
USPS:     P.O.Box 400400    Charlottesville, VA 22904-4400
Parcels:    Room 102        Gilmer Hall
         McCormick Road    Charlottesville, VA 22903
Office:    B011    +1-434-982-4729
Lab:        B019    +1-434-982-4751
Fax:        +1-434-982-4766
WWW:    http://www.people.virginia.edu/~mk9y/

maybe something like:

dotplot(type ~ lodds, scales = list(x = list(at = -5:0, labels = 
round(plogis(-5:0), 3))))

could do the trick; I hope it helps.

Best,
Dimitris

----
Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/(0)16/336899
Fax: +32/(0)16/337015
Web: http://www.med.kuleuven.be/biostat/
     http://www.student.kuleuven.be/~m0390867/dimitris.htm


----- Original Message ----- 
From: "Michael Kubovy" <kubovy at virginia.edu>
To: <r-help at stat.math.ethz.ch>
Sent: Friday, April 14, 2006 3:29 PM
Subject: [R] Dotplot x-axis

> Here's a small dataset:
>
> type <-
c('hierarchical','partial','single','complete','single
>
+hierarchical','single+partial','partial+hierarchical','single+partial
> +hierarchical')
> freq <- c(1455,729,688,65,29,28,16,17)
> lodds <- log(freq/(3027 - freq))
> dotplot(type~lodds)
>
> I would like to have the x-axis have ticks at nice, close to 
> equally-
> spaced values, of the proportions rather than at round log-odds
> values, which appear as -5:0. For example: perhaps have ticks at c
> (0.007, 0.02, 0.05, 0.12, 0.27, 0.5), which are approximate values 
> of
> exp(-5:0)/(1+exp(-5:0))
>
> Advice?
> _____________________________
> Professor Michael Kubovy
> University of Virginia
> Department of Psychology
> USPS:     P.O.Box 400400    Charlottesville, VA 22904-4400
> Parcels:    Room 102        Gilmer Hall
>         McCormick Road    Charlottesville, VA 22903
> Office:    B011    +1-434-982-4729
> Lab:        B019    +1-434-982-4751
> Fax:        +1-434-982-4766
> WWW:    http://www.people.virginia.edu/~mk9y/
>
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide! 
> http://www.R-project.org/posting-guide.html
> 

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