Prof. David Horn (TAU) Date: Apr. 26, 2009 Title: Finding structures in data Abstract: Given a set of data-points (instances) in a general parameter-space (features) one may be interested in finding relationships among the data (e.g. clustering) or establishing which are the most relevant parameters (feature selection). These are typical problems in biology and medicine as well as in many other fields. After an introduction to preprocessing techniques, we will discuss two novel methods, UFF (unsupervised feature filtering) and DQC (dynamic quantum clustering), and exhibit their results on various examples. UFF ranks features according to their contribution to an entropy-measure of the eigenvalues of the correlation matrix. DQC maps data points into states of an Hilbert-space. Based on an appropriately chosen potential function, it allows the user to trace the motion of these states in a time-dependent Schrodinger equation and deduce relationships among data-points accordingly.