1. A method of searching for a query object within an object class, said method comprising: (a) accessing a collection of unique training samples of multiple training objects within said object class; (b) defining a separate training set of training item descriptors from each of said training samples; (c) extracting the training item descriptors from the separate training sets into a single composite collection of individual training item descriptors; (d) creating a hierarchical tree from said composite collection of individual training item descriptors according to relations in the individual training item descriptors, said hierarchical tree having a plurality of leaf nodes; (e) accessing registration sets of registration item descriptors, each registration set being defined from a respective registration sample obtained from a registration objects to be registered, said registration object being of said object class, individually distributing each registration item descriptor from each registration set into said hierarchical tree according to said relations defined in the creation of said hierarchical tree, indexing the registration item descriptors clustered within each leaf node to their corresponding registration samples; (f) defining a separate registration model for each registration sample based on the clustering of its corresponding registration item descriptors in each leaf node; (g) accessing a query sample from said query object, defining a query set of query item descriptors from said query sample, individually distributing each query item descriptor into said hierarchical tree according to said relations defined in the creation of said hierarchical tree; (h) defining a query model for said query sample based on the clustering of said query item descriptors in each leaf node; and (i) using the query model, x, and the registration models to identify as a potential candidate match the registration object, i, that renders the highest confidence i* of matching the query object, defined as i*=arg max i P(x|i)P(i).