How to increase the size of numbers (mean and stdev (xxx xxx) inside the box plot bar; or the P-value size on graph?

[#1]

[#2]

Welcome to the community.  I'm not certain on this particular plot, but right click is your friend.  Try right clicking on the graph, you get a menu of options including customize.  This may allow you to change font characteristics.

[#3]

I haven't seen a way to do it, but others at my company have expressed interest in this feature. If it really isn't available, it might be a good idea for the wish list.  https://community.jmp.com/t5/JMP-Wish-List/idb-p/jmp-wish-list

[#4]

I am not sure where this plot appears in JMP. I used Graph Builder to make a similar plot and add the 'five-point summary' to it. Afterward, I right-clicked in the plot frame and selected Customize. I selected on of the Text items in the list on the left side, clicked Font, and changed the size. Here is the result for my example:

[#5]

Sorry, in my earlier comment, I thought the original post was referencing a Graph Builder output, but that may not be the case.

In Graph Builder, I suppose it depends on the Graph Builder output type.  For boxplots, I see I can right click and customize the text for the 5 point summary as Mark mentions. This appears to be the only labeling apart from hover labels.  For a bar charts, which I use for pareto plots, there's an option to add a label (label by value, for example).  I don't see an option to customize this text.