Efficient Second-Order Shape-Constrained Function Fitting



Durfee, David, Gao, Yu, Rao, Anup B and Wild, Sebastian ORCID: 0000-0002-6061-9177
(2019) Efficient Second-Order Shape-Constrained Function Fitting. .

Warning
There is a more recent version of this item available.
[thumbnail of 1905.02149v2.pdf] Text
1905.02149v2.pdf - Submitted version

Download (720kB) | Preview

Abstract

We give an algorithm to compute a one-dimensional shape-constrained function that best fits given data in weighted-L∞$$L_{\infty }$$ norm. We give a single algorithm that works for a variety of commonly studied shape constraints including monotonicity, Lipschitz-continuity and convexity, and more generally, any shape constraint expressible by bounds on first- and/or second-order differences. Our algorithm computes an approximation with additive error ϵ$$\epsilon $$ in OnlogUϵ$$O\left( n \log \frac{U}{\epsilon } \right) $$ time, where U captures the range of input values. We also give a simple greedy algorithm that runs in O(n) time for the special case of unweighted L∞$$L_{\infty }$$ convex regression. These are the first (near-)linear-time algorithms for second-order-constrained function fitting. To achieve these results, we use a novel geometric interpretation of the underlying dynamic programming problem. We further show that a generalization of the corresponding problems to directed acyclic graphs (DAGs) is as difficult as linear programming.

Item Type: Conference Item (Unspecified)
Additional Information: accepted for WADS 2019; (v2 fixes various typos)
Uncontrolled Keywords: 46 Information and Computing Sciences
Depositing User: Symplectic Admin
Date Deposited: 15 Aug 2019 14:38
Last Modified: 13 May 2025 17:20
DOI: 10.1007/978-3-030-24766-9_29
Related Websites:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3051854

Available Versions of this Item