Graph to show that very few classes has maximum best performers

Hello

I need help for the following:

my data is
class no. best performers
101      10
102      21
103       1
104       3
105       5
106    190
...    ...
...    ...
...    ...
...    ...

I want to plot a graph using R, to show that very few classes has maximum
best performers. can someone guide me for this? I tried using cumulative
frequencies and then plotting a graph but it does not serve the purpose.
   

Hi Sunita,
Maybe this will do what you want:

sundat
   class_no best_performers
1      101              10
2      102              21
3      103               1
4      104               3
5      105               5
6      106             190

library(plotrix)
staircase.plot(sundat$best_performers,
  labels=paste("Class",sundat$class_no),
  inc.col="blue",direction="s",
  totals=c(TRUE,rep(FALSE,dim(sundat)[1]-1)),
  main="Best performers by class")

Jim

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Hello Jim

This seems to work but the problem is my dataset is very large so the 
image is not coming clear, its all mixed up. my dataset contains 150 
rows. in such case what has to be done?

Hi Sunita,
I don't think that staircase.plot will be suitable for 150 values unless 
you define a very large device of almost a meter in the direction of 
plotting. Try this and see how you like it:

x11(width=15,height=4)
plot(sundat$class_no,sundat$best_performers,
  type="h",xaxt="n",xlab="Class number",
  ylab="Number of best performers",
  main="Best performers by class")
library(plotrix)
staxlab(at=class_no,labels=class_no,
  nlines=3,line.spacing=0.5,cex=0.5)

Jim