As time goes along, my number of groups increases. Now, I have a lot. I really hope I can organize them in a certain way. E.g, some of them belong to"physics". Some of them belong to “statistics”. So I am wondering whether Endnote provide any functions to let me organize my groups in a hierarchical format? If it is, how?
EndNote X3 is capable of two-level nesting and there’s also the “smart group” feature which enables automatic grouping of references based on self-identified key words.
The EndNote Product Suggestions section of the forum contains suggestions to the product development team. If EndNote is currently unable to address your needs concerning groups, the “Suggestions” forum is the place to toss some ideas out.
As CrazyGecko suggests, Endnote X3 introduced a level of hiearchy for groups (“Group Sets”).
See the EnX3 manual:
"Using Custom Group Sets
Before long, you could have a large number of groups in your library. To help organize your groups, you can create up to 500 custom Group Sets. Custom group sets can contain any combination of custom groups and smart groups…"