We describe here preliminary results of our Comet implementation of generic abstractions for Very LargeScale Neighborhoods. These neighborhoods are used in local search. Their size is exponential but the best neighbor can be computed in polynomial time. They have proven to be very efficient on a large set of problems. However designing such neighborhoods requires high development efforts. Our o...

In the Euclidean TSP with neighborhoods (TSPN) problem we seek a shortest tour that visits a given set of n neighborhoods. The Euclidean TSPN generalizes the standard TSP on points. We present the first constant-factor approximation algorithm for TSPN on an arbitrary set of disjoint, connected neighborhoods in the plane. Prior approximation bounds were O(log n), except in special cases. Our app...

We tested the hypothesis that neighborhoods with hazardous waste sites may no longer be undesirable places to live if they have been at least partly remediated. We collected 377 questionnaires (42% response rate) administered from within one-half mile of the number 1, 4, and 12 hazardous waste sites on the National Priority List (Superfund). These neighborhoods were rated higher quality than ne...

The geographic concentration and diffusion of crime deviancy are longstanding criminological inquiries, yet few studies have examined how certain illicit behaviors transcend neighborhood borders connect neighborhoods in patterns deviancy. A structural interdependence may account for the enduring nature spread crime, making it critical to understand connected guide prevention disruption efforts....

We evaluate the relationship between job proximity and male joblessness at the neighborhood level in Cleveland and Milwaukee. Using two tract-level measures of proximity to employment (i.e., physical distance and commute time), we Žnd mixed evidence for the spatial mismatch hypothesis. As expected, we Žnd that predominantly black neighborhoods in both cities have higher rates of male joblessnes...

Fertility levels remain high in most of sub-Saharan Africa, despite recent declines, and even in a large capital city such as Accra, Ghana, women are having children at a pace that is well above replacement level and this will contribute to significant levels of future population growth in the city. Our purpose in this paper is to evaluate the way in which neighborhood context may shape reprodu...

The purpose of this study was to determine whether the availability and accessibility of physical activity resources differed by neighborhood socioeconomic status (SES) in a small U.S. city (population = 133,046). U.S. census tracts (N =32) were used to represent neighborhoods and categorized into high, medium, or low SES on the basis of the percentage of unemployed individuals, per capita inco...

APrIl 2017 IZA DP No. 10697 The Effects of Physical Restructuring on the Socioeconomic Status of Neighborhoods: Selective Migration and Upgrading In the last few decades, urban restructuring programs have been implemented in many Western European cities with the main goal of combating a variety of socioeconomic problems in deprived neighborhoods. The main instrument of restructuring has been ho...

Indexing methods for the approximate string matching problem spend a considerable effort generating condensed neighborhoods. Condensed neighborhoods, however, are not a minimal representation of a pattern neighborhood. Super condensed neighborhoods, proposed in this work, are smaller, provably minimal and can be used to locate approximate matches that can later be extended by on-line search. We...

This study examined the association of census level, observational, and parent-reported neighborhood characteristics on the verbal and behavioral competencies of a national sample of Canadian preschoolers (N = 3,350). Children's verbal ability scores were positively associated with residing in neighborhoods with affluent residents and negatively associated with residing in neighborhoods with po...