All the clever computing and the statistical theory that drives that are from Wolfgang Viechtbauer's brilliant R package: metafor and specifically from his conv.fivenum() function.
I have left the function to use its default estimation method: 'luo/wan/shi'. The references for that, which I am sure are too sophisticated for me, can be found in the help page for the function. The background is in the comprehensive help page for the function .
I have added the plot which I hope is of some pedagogical usefulness (it helped me understand things!). The quartiles are drawn from R's dnorm() function but the minima and maxima I created by simulating 100 samples from a Gaussian distribution with the estimated mean, SD and n and taking the mean minimum and maximum across those 100 simulated samples. Clearly, the larger the n, the wider out the observed minimum and maximum will be, though the extent to which the observed limits widen with increasing n falls rapidly as n gets to sensible dataset sizes.
App created 6.iv.25 by Chris Evans PSYCTC.org
Last updated 6.iv.25: so no updates yet!
Licenced under a Creative Commons, Attribution Licence-ShareAlike Please respect that and put an acknowledgement and link back to here if re-using anything from here.
Background and related resources
This shiny app is one of a growing number in, my shiny serverThey complement:
- my Rblog of posts about using R
- the glossary linked with
- the OMbook
- the CECPfuns R package
- and it's all part of the resources of PSYCTC.org
- and linked with the CORE system web site
There is a form if you want to contact me: so do please use that if you think there is anything wrong here or anything that could be improved.
There is also now an Email announcement list, never updating more than monthly, where I will put up developments of new apps here, a summary of updates to the glossary and new posts in the Rblog. You can sign up for that here.