5. A system according to claim 1 , wherein the central processing unit generates one such spine group by arranging two or more clusters of documents along a spine based on concepts of the clusters and grafting at least one other spine of clusters to one of the clusters arranged along the spine.
5. A system according to claim 1 , wherein the central processing unit generates one such spine group by arranging two or more clusters of documents along a spine based on concepts of the clusters and grafting at least one other spine of clusters to one of the clusters arranged along the spine. 8. A system according to claim 5 , wherein the central processing unit places a different spine of clusters having less similarity to the clusters arranged along the spine adjacent one of the clusters arranged along with spine that is most similar to the different spine of clusters.