Interpreting box plots

[Tracy Lam]

I have some box plots that I am using to inspect outliers. I do have some outliers that fall outside of the plot. I have two outliers that are illustrated with a dot. Does each outlier dot represent a single observation or multiple observations?

Also, what is the suggested way to check for outliers besides box plots?

[Nick Cox]

Symbols plotted separately could represent multiple points. I can't see that graph box graph hbox or supports jitter() to shake them apart.

What is an outlier is more than a univariate question, but I would use something like quantile to look at individual distributions and graph matrix for bivariate views,