| Popis: |
We propose a new method for representing data sets with a set of binary feature functions. We compute both the dyadic set structure determined by an order on the binary features together with the canonical product coefficient parameters for the associated dyadic measure and a variant of a nerve simplicial complex determined by the support of the dyadic measure together with its betti numbers. The product coefficient parameters characterize the relative skewness of the dyadic measure at dyadic scales and localities. The more abstract betti number statistics summarize the simplicial geometry of the support of the measure and satisfy a differential privacy property. Both types of statistics can be computed algorithmically from the binary feature representation of the data. This representation provides a new method for pre-processing data into automatically generated features which explicitly characterize the dyadic statistics and geometry of the data. useful for statistical fusion, decision-making, inference, multi-scale hypothesis testing and visualization. We illustrated the methods on a data quality data set. We exploit a representation lemma for dyadic measures on the unit interval (Fefferman, Kenig and Pipher) reformulated for measures on dyadic sets by Bassu, Jones, Ness and Shallcross. We prove that dyadic sets with dyadic measures have a canonical set of binary features and determine canonical nerve simplicial complexes. We compare our methods with other results for measures on sets with tree structures, recent multi-resolution theory, and persistent homology and suggest links to differential privacy, Bayesian reasoning and algebraic statistics. |
