rggplot2traminer

Sequence index plots in ggplot2 using geom_tile( )

I'm trying to use ggplot to create sequence plots, for the sake of keeping the same visual style within my paper using sequence analysis. I do:

library(ggplot2)
library(TraMineR)
library(dplyr)
library(tidyr)    
data(mvad)    
mvad_seq<-seqdef(mvad,15:length(mvad))
mvad_trate<-seqsubm(mvad_seq,method="TRATE")
mvad_dist<-seqdist(mvad_seq,method="OM",sm=mvad_trate)
cluster<-cutree(hclust(d=as.dist(mvad_dist),method="ward.D2"),k=6)
mvad$cluster<-cluster
mvad_long<-gather(select(mvad,id,contains("."),-matches("N.Eastern"),-matches("S.Eastern")),
                    key="Month",value="state",
                    Jul.93, Aug.93, Sep.93, Oct.93, Nov.93, Dec.93, Jan.94, Feb.94, Mar.94,
                    Apr.94, May.94, Jun.94, Jul.94, Aug.94, Sep.94, Oct.94, Nov.94, Dec.94, Jan.95,
                    Feb.95, Mar.95, Apr.95, May.95, Jun.95, Jul.95, Aug.95, Sep.95, Oct.95, Nov.95,
                    Dec.95, Jan.96, Feb.96, Mar.96, Apr.96, May.96, Jun.96, Jul.96, Aug.96, Sep.96,
                    Oct.96, Nov.96, Dec.96, Jan.97, Feb.97, Mar.97, Apr.97, May.97, Jun.97, Jul.97,
                    Aug.97, Sep.97, Oct.97, Nov.97, Dec.97, Jan.98, Feb.98, Mar.98, Apr.98, May.98,
                    Jun.98, Jul.98, Aug.98, Sep.98, Oct.98, Nov.98, Dec.98, Jan.99, Feb.99, Mar.99,
                    Apr.99, May.99, Jun.99)

mvad_long<-left_join(mvad_long,select(mvad,id,cluster))
ggplot(data=mvad_long,aes(x=Month,y=id,fill=state))+geom_tile()+facet_wrap(~cluster)

I try to plot the sequences by cluster, and this gives me the following plot:Sequence index plot with ggplot

As you can see, there are gaps for the ids that don't belong to the cluster represented by each facet. I would like to get rid of these gaps, so that the sequences show up stacked just as with the seqIplot() function of TraMineR as in the next figure: SeqIplot

Any suggestions of how to proceed?

Solution

  • Two small changes:

    mvad_long$id <- as.factor(mvad_long$id)
ggplot(data=mvad_long,aes(x=Month,y=id,fill=state))+
       geom_tile()+facet_wrap(~cluster,scales = "free_y")

    ggplot was treating id as a numerical variable, rather than a factor, and then the scales were fixed.