The rank problem in succinct data structures asks to preprocess an array A[1 . . n] of bits into a data structure using as close to n bits as possible, and answer queries of the form Rank(k) = ∑k i=1 A[i]. The problem has been intensely studied, and features as a subroutine in a majority of succinct data structures. We show that in the cell probe model with w-bit cells, if rank takes t time, th...

A distinctive feature of a clustered observational study is its multilevel or nested data structure arising from the assignment of treatment, in a non-random manner, to groups or clusters of units or individuals. Examples are ubiquitous in the health and social sciences including patients in hospitals, employees in firms, and students in schools. What is the optimal matching strategy in a clust...

Harmful Algal Blooms (HAB) events may have serious economic consequences for shellfish farmers. When toxic algae blooms threaten human health, public authorities decide to shut down the farming business a while, i.e. ranging from few days several weeks or months, according severity of risks. The impact closures being temporally and spatially distributed, farmers can avoid risky zones develop ad...

This work exploits the resemblance between content-based image retrieval and image analysis with respect to the design of image descriptors and their effectiveness. In this context, two shape descriptors are proposed: contour saliences and segment saliences. Contour saliences revisits its original definition, where the location of concave points was a problem, and provides a robust approach to ...

The bipartite matching model was born in the work of Gale and Shapley, who proposed the stable marriage problem in the 1960s. In this paper we consider a dynamic setting, modeled as a multi-class queueing network or MDP model. The goal is to compute a policy for the matching model that is optimal in the average cost sense. Computation of an optimal policy is not possible in general, but we obta...

Matching on the propensity score is a commonly used analytic method for estimating the effects of treatments on outcomes. Commonly used propensity score matching methods include nearest neighbor matching and nearest neighbor caliper matching. Rosenbaum (1991) proposed an optimal full matching approach, in which matched strata are formed consisting of either one treated subject and at least one ...

Les documents de travail ne reflètent pas la position de l'INSEE et n'engagent que leurs auteurs. Working papers do not reflect the position of INSEE but only the views of the authors. 1 This working paper is a reflection on the conditions required to use optimal matching (OM) in social sciences. Despite its striking success in biology, optimal matching was not invented to solve biological ques...