Relationship between education, health and crime: fable, fallacy or fact

The study is an empirical evaluation of specific criminal activities. The relationship of criminal activities with inflation, unemployment, investment, education and health are examined through an annual data set from 1980 to 2007. To test the order of integration, Augmented Dickey Fuller test and Philips Perron are used. To find the evidences of long run relationship, Cointegrating Regression Durban Watson, Engle Granger two step procedure and Johansen and Juselis method is used. Results show that education and health have a positive and significant relationship with most of the criminal activities in the study. Another unusual finding is that inflation and unemployment are insignificant in case of two out of three crimes, however, investment is found highly significant and negatively related with these crimes. The study indicates that an educated, healthy and legally employed person can also be involved in unsophisticated blue collar criminal activities.Education; health; Crime

Intertemporal and interspatial comparisons of income : the meaning of relative prices

The conceptual issues confronting compilers of price indices have not changed much over the years. They include the intractability of basic index-number problems, the practical difficulties of sampling and matching prices, and the uncertainties about the appropriate weighting scheme for comparing events in specific locales over time and across locales. The author considers inconsistencies in some measures of time-to-time and place-to-place comparisons of income. He argues for a method that harmonizes price work across generally recognized national price compilations, such as consumer price indices (CPSs), the International Comparison Programme (ICP), and national accounting. Modern economies tend to be more open, so relative prices should be more similar, but it is increasingly apparent that price levels and trends can differ considerably even within a nation - particularly those encompassing economically heterogeneous areas. The global ICP exercise has provided useful insights into the issues involved. At the same time, international comparisons of the type ICP aims to facilitate are now seen as being more sensitive than expected to changes in relative prices. ICP has given little attention to this issue, but there is a rich literature on the subject with respect to CPS. The common ground for the two logics is essentially national accounts, broadly defined. Through conceptual and practical work done by the World Bank on the topic, the author suggests that harmonizing the various methods is essential to a proper interpretation of the market signals that prices send to economic agents. He also explains how a better synthesis reduces the overall cost of collecting relevant information and disseminating it to users.Environmental Economics&Policies,Economic Theory&Research,Information Technology,Markets and Market Access,Access to Markets

Contracting Boundaries of CAT(0) Spaces

As demonstrated by Croke and Kleiner, the visual boundary of a CAT(0) group is not well-defined since quasi-isometric CAT(0) spaces can have non-homeomorphic boundaries. We introduce a new type of boundary for a CAT(0) space, called the contracting boundary, made up rays satisfying one of five hyperbolic-like properties. We prove that these properties are all equivalent and that the contracting boundary is a quasi-isometry invariant. We use this invariant to distinguish the quasi-isometry classes of certain right-angled Coxeter groups.Comment: 27 pages, 8 figure

Optimal Selection of Spectrum Sensing Duration for an Energy Harvesting Cognitive Radio

In this paper, we consider a time-slotted cognitive radio (CR) setting with buffered and energy harvesting primary and CR users. At the beginning of each time slot, the CR user probabilistically chooses the spectrum sensing duration from a predefined set. If the primary user (PU) is sensed to be inactive, the CR user accesses the channel immediately. The CR user optimizes the sensing duration probabilities in order to maximize its mean data service rate with constraints on the stability of the primary and cognitive queues. The optimization problem is split into two subproblems. The first is a linear-fractional program, and the other is a linear program. Both subproblems can be solved efficiently.Comment: Accepted in GLOBECOM 201

The Asymptotic Cone of Teichm\"uller Space: Thickness and Divergence

We study the Asymptotic Cone of Teichm\"uller space equipped with the Weil-Petersson metric. In particular, we provide a characterization of the canonical finest pieces in the tree-graded structure of the asymptotic cone of Teichm\"uller space along the same lines as a similar characterization for right angled Artin groups by Behrstock-Charney and for mapping class groups by Behrstock-Kleiner-Minksy-Mosher. As a corollary of the characterization, we complete the thickness classification of Teichm\"uller spaces for all surfaces of finite type, thereby answering questions of Behrstock-Drutu, Behrstock-Drutu-Mosher, and Brock-Masur. In particular, we prove that Teichm\"uller space of the genus two surface with one boundary component (or puncture) can be uniquely characterized in the following two senses: it is thick of order two, and it has superquadratic yet at most cubic divergence. In addition, we characterize strongly contracting quasi-geodesics in Teichm\"uller space, generalizing results of Brock-Masur-Minsky. As a tool, we develop a complex of separating multicurves, which may be of independent interest.Comment: This paper comprises the main portion of the author's doctoral thesis, 54 page