Just at the moment it is maps. I have been pursuing poetry (of the twentieth century in English, mostly UK writers) though the means of anthologies. Those collections come in a number of kinds: Modernist Poetry's Greatest Hits, Now That's What I Call Poetry About Domestic Animals 14, These Love Verses You Have Loved, Some Poems By My Friends And Some of Mine Too. I exaggerate, but I'm sure the point is clear: one can expect to get some sort of map out of collections of poems (of poets) grouped in some way, but first one has to discriminate in order to get data which deserves to be taken collectively.
That a map is sought after seems clear: http://www.bigbridge.org/lmfulcrum.htm on the position in 2002. All those big fat books prompted by the millennial milestone, and the situation for poetry is still less clear than, for example, with popular music even in today's fragmented state. There are 'tribal' loyalties within groups of poets, national classifications which may or may not matter much, a huge number of published poets (well into five figures, I guess) and of course not enough success to go around just like in the academic world to which poetry has become closer.
There is something that works, for me: the importance of the minor poet. Seemed like serendipity but I now have a map in working form. Like this: from nearly 50 anthologies chosen on a principled basis (representing a period or a personal taste of a poet) look for poets who are represented in exactly two. Draw the graph (vertices = anthologies, edges = minor poets) and you have your map. Well, I have mine, and most interesting too. Seems there was a real blockage in British poetry mid-century, represented by the taste of Philip Larkin (the so-called Movement Poets' top guy); and the way round was difficult except via surrealist poetry and American influence.
All highly questionable no doubt, but at least much less subjective than what you read in the introductions to the books themselves. Why does this do anything at all? Anthologies as collections are typically 'group portraits' or 'acts of criticism': they represent the poetry of a certain place and time, or poems with some attributes valued by the compiler. Major poets will force themselves into large numbers of anthologies, so in a map will represent whole regions. Having 'enough' minor poets to fill in the details of the map seems not to be a problem in the twentieth century, a comment on education and the influence, doubtless, of some major stars such as Yeats and Eliot and Auden.
So this all depends, I guess, on two factors: definite taste and discrimination by critical compilers, so that they are mapping out a distinctive corner rather than just compiling celebrities; and the plenitude of poets so that potential linkages are realised. As an example, the Yeats 'Oxford Book of Modern Verse' is seen to have little in common with a standard 1914-18 War Poets collection. It isn't hard to understand why that might be; but it does suggest that the general 'Georgian' label applied to British poets from 1910 needs close scrutiny.
So much for one tangle. It's really a story of the least obvious connections carrying a heavy information-theoretic load. --CharlesMatthews
See also EarlyPoetryAndWiki.