@inbook {IOPORT.05960463, author = {Dalalyan, Arnak S. and Salmon, Joseph}, title = {Competing against the best nearest neighbor filter in regression.}, year = {2011}, booktitle = {Algorithmic learning theory. 22nd international conference, ALT 2011, Espoo, Finland, October 5--7, 2011. Proceedings}, isbn = {978-3-642-24411-7}, pages = {129-143}, publisher = {Berlin: Springer}, doi = {10.1007/978-3-642-24412-4_13}, abstract = {Summary: Designing statistical procedures that are provably almost as accurate as the best one in a given family is one of central topics in statistics and learning theory. Oracle inequalities offer then a convenient theoretical framework for evaluating different strategies, which can be roughly classified into two classes: selection and aggregation strategies. The ultimate goal is to design strategies satisfying oracle inequalities with leading constant one and rate-optimal residual term. In many recent papers, this problem is addressed in the case where the aim is to beat the best procedure from a given family of linear smoothers. However, the theory developed so far either does not cover the important case of nearest-neighbor smoothers or provides a suboptimal oracle inequality with a leading constant considerably larger than one. In this paper, we prove a new oracle inequality with leading constant one that is valid under a general assumption on linear smoothers allowing, for instance, to compete against the best nearest-neighbor filters.}, identifier = {05960463}, }