Jump to content

  • Log in with Facebook Log in with Twitter Log in with Windows Live Log In with Google      Sign In   
  • Create Account

Submit your paper to J Biol Methods today!
- - - - -

How to denote letters to mark significant differences in a bar chart plot

Biostatistics Data Interpretation Life Science

  • Please log in to reply
2 replies to this topic




  • Active Members
  • Pip
  • 15 posts

Posted 25 December 2012 - 04:02 AM

Need your help to find a solution for my problem to indicate significant differences in a bar chart plot. The data of the statistical test is available in the following format:


Bar1-bar3:not significant

I want to mark significant differences between two bars with different letters (like bar1:a and bar2: b. If there is no significant differences between two bars they get the same letter (like bar1:a and bar3:a). Sort the right letters to the bars gets much more complex when the number of bars increases. I have several hundreds of statistical comparisons here and have to find a computer program that can generate the letters from the data for me.

Anybody an idea which programme can help me?

I have added an example plot with letter-coded significant differences to illustrate what I want to do.

*** If any one can help me to obtain a good reference material that guide to Interpretation and analysis of biological research data would be much grateful.

Attached a sample e.g.

Attached Thumbnails

  • file.PostFileLoader (1).jpg
  • file.PostFileLoader (3).jpg

Edited by Akila Wijerathna Yapa, 25 December 2012 - 04:03 AM.

#2 pcrman



  • Global Moderators
  • PipPipPipPipPipPipPipPipPipPip
  • 1,165 posts

Posted 25 December 2012 - 05:47 AM

To my best knowledge, there is no such program that can automatically add letters, draw lines between comparisons. I do this in photoshop after pasting the bar figures from Excel. I am not sure whether R package can be of help if you have lots of figures to work with.

#3 hobglobin


    Growing old is mandatory, growing up is optional...

  • Global Moderators
  • PipPipPipPipPipPipPipPipPipPip
  • 5,604 posts

Posted 25 December 2012 - 05:49 AM

Yes it becomes complicated, but not only for you but also for the reader....it would be a good idea to reduce the complexity in a way that a reader has a chance to get an idea about these results in reasonable time.

One must presume that long and short arguments contribute to the same end. - Epicurus
...except casandra's that did belong to the funniest, most interesting and imaginative (or over-imaginative?) ones, I suppose.

Home - About - Terms of Service - Privacy - Contact Us

©1999-2013 Protocol Online, All rights reserved.