Learning analytics is focused on the educational challenge of optimizing opportunities for meaningful learning. Assessment deeply influences learning, but at the same time data about assessment are rarely considered and utilized by learning analytics. Current approaches to analysis and reasoning about peerassessment lack rigor and appropriate measures of reliability assessment. Our paper addres...

Taxicab service plays a vital role in public transportation by offering passengers quick personalized destination service in a semiprivate and secure manner. Taxicabs cruise the road network looking for a fare at designated taxi stands or alongside the streets. However, this service is often inefficient due to a low ratio of live miles (miles with a fare) to cruising miles (miles without a fare...

BACKGROUND Driving a taxicab remains one of the most dangerous occupations in the United States, with leading homicide rates. Although safety equipment designed to reduce robberies exists, it is not clear what effect it has on reducing taxicab driver homicides. FINDINGS Taxicab driver homicide crime reports for 1996 through 2010 were collected from 20 of the largest cities (>200,000) in the U...

We describe algorithmic results for two crucial aspects of allocating resources on computational hardware devices with partial reconfigurability. By using methods from the field of computational geometry, we derive a method that allows correct maintainance of free and occupied space of a set of n rectangular modules in optimal time Θ(n log n); previous approaches needed a time of O(n) for corre...

This paper studies how firms reorganize following diversification, proposing that firms use outsourcing, or vertical disintegration, to manage diseconomies of scope. We also consider the origins of scope diseconomies, showing how different underlying mechanisms generate contrasting predictions about the link between within-firm task heterogeneity and the incentive to outsource following diversi...

We study the Cauchy problem for a strictly hyperbolic n×n system of conservation laws in one space dimension: ut + f(u)x = 0, u(0, x) = ū(x). The initial data ū is a small BV perturbation of a single rarefaction wave with an arbitrary strength. All characteristic fields are assumed to be genuinely nonlinear or linearly degenerate in the vicinity of the reference rarefaction curve. We prove that...

In this paper, we develop an analytic solution for the best one-sided approximation of polynomials under L1 norm, that is, we 0nd two polynomials with lower degree which bound the given polynomial such that the areas between the bounding polynomials and the given polynomial attain minimum. The key ingredient of our technique is a characterization for one-sided approximations based on orthogonal...

Recently, In [Phys. Rev. Lett. 104, 018701 (2010)] the authors studied a spatial network which is constructed from a regular lattice by adding long-range edges (shortcuts) with probability Pij ∼ r −α ij , where rij is the Manhattan length of the long-range edges. The total length of the additional edges is subject to a cost constraint ( ∑ r = C). These networks have fixed optimal exponent α for...

The Canberra distance is the sum of absolute values of the differences between ranks divided by their sum, thus it is a weighted version of the L1 distance. As a metric on permutation groups, the Canberra distance is a measure of disarray for ranked lists, where rank differences in top positions need to pay higher penalties than movements in the bottom part of the lists. Here we describe the di...

For d ∈ N and Ω 6= ∅ an open set in R, we consider the eigenfunctions Φ of the Dirichlet Laplacian −∆Ω of Ω. If Φ is associated with an eigenvalue below the essential spectrum of −∆Ω we provide estimates for the L1-norm of Φ in terms of its L2-norm and spectral data. These L1estimates are then used in the comparison of the heat content of Ω at time t > 0 and the heat trace at times t′ > 0, wher...