The Effectiveness of Juvenile Correctional Facilities: Public versus Private Management

This paper uses data on juvenile offenders released from correctional facilities in Florida to explore the effects of facility management type (private for-profit, private nonprofit, public state-operated, and public county-operated) on recidivism outcomes and costs. The data provide detailed information on individual characteristics, criminal and correctional histories, judge-assigned restrictiveness levels, and home zipcodes—allowing us to control for the non-random assignment of individuals to facilities far better than any previous study. Relative to all other management types, for-profit management leads to a statistically significant increase in recidivism, but, relative to nonprofit and state-operated facilities, for-profit facilities operate at a lower cost to the government per comparable individual released. Costbenefit analysis implies that the short-run savings offered by for-profit over nonprofit management are negated in the long run due to increased recidivism rates, even if one measures the benefits of reducing criminal activity as only the avoided costs of additional confinement.Juvenile Crime; Juvenile Correctional Facilities; Recidivism; Prison Privatization; Provision of Public Goods: Nonprofit, For-profit, Public

Genetic algorithms

Genetic algorithms are mathematical, highly parallel, adaptive search procedures (i.e., problem solving methods) based loosely on the processes of natural genetics and Darwinian survival of the fittest. Basic genetic algorithms concepts are introduced, genetic algorithm applications are introduced, and results are presented from a project to develop a software tool that will enable the widespread use of genetic algorithm technology

Signatures of hermitian forms and the Knebusch Trace Formula

Signatures of quadratic forms have been generalized to hermitian forms over algebras with involution. In the literature this is done via Morita theory, which causes sign ambiguities in certain cases. In this paper, a hermitian version of the Knebusch Trace Formula is established and used as a main tool to resolve these ambiguities. The last page is an erratum for the published version. We inadvertently (I) gave an incorrect definition of adjoint involutions; (II) omitted dealing with the case $(H\times H, \widehat{\phantom{m}}\,)$. As $W(H\times H, \widehat{\phantom{m}}\,)= W(R\times R, \widehat{\phantom{m}}\,)=0$, the omission does not affect our reasoning or our results. For the sake of completeness we point out where some small changes should be made in the published version.Comment: This is the final version before publication. The last page is an updated erratum for the published versio

Building Criminal Capital Behind Bars: Social Learning in Juvenile Corrections

This paper analyzes the influence that juvenile offenders serving time in the same correctional facility have on each other's subsequent criminal behavior. The analysis is based on data on over 8,000 individuals serving time in 169 juvenile correctional facilities during a two-year period in Florida. These data provide a complete record of past crimes, facility assignments, and arrests and adjudications in the year following release for each individual. To control for the non-random assignment of juveniles to facilities, we include facility fixed effects in the analysis. This ensures that the impact of peers on recidivism is identified using only the variation in the length of time that any two individuals serving a sentence in the same facility happen to overlap. We find strong evidence of peer effects for various categories of theft, burglary, and felony drug and weapon crimes; the influence of peers primarily affects individuals who already have some experience in a particular crime category.social learning, peer effects, social interactions, recidivism, juvenile crime, human capital accumulation

Forster signatures and qubits in optically driven quantum dot molecules

An interesting approach to achieve quantum gate operations in a solid state device is to implement an optically driven quantum gate using two vertically coupled self-assembled quantum dots, a quantum dot molecule (QDM). We present a realistic model for exciton dynamics in InGaAs/GaAs QDMs under intense laser excitation and applied electric fields. The dynamics is obtained by solutions of the Lindblad master equation. A map of the dressed ground state as function of laser energy and applied electric field exhibits rich structure that includes excitonic anticrossings that permit the identification of the relevant couplings. The optical signatures of the dipole-dipole Forster energy transfer mechanism show as splittings of several (spatially) indirect excitonic lines. Moreover, we construct a model for exciton qubit rotations by adiabatic electric field cyclic sweeps into a Forster-tunneling regime which induces level anticrossings. The proposed qubit exhibits Rabi oscillations among two well defined exciton pairs as function of the residence time at the anticrossing.Comment: Paper presented in the International Conference on Electronic Properties of Two-dimensional Systems and Modulated Semiconductor Structures Genova Magazzini del Cotone, July 15-20 200

Division, adjoints, and dualities of bilinear maps

The distributive property can be studied through bilinear maps and various morphisms between these maps. The adjoint-morphisms between bilinear maps establish a complete abelian category with projectives and admits a duality. Thus the adjoint category is not a module category but nevertheless it is suitably familiar. The universal properties have geometric perspectives. For example, products are orthogonal sums. The bilinear division maps are the simple bimaps with respect to nondegenerate adjoint-morphisms. That formalizes the understanding that the atoms of linear geometries are algebraic objects with no zero-divisors. Adjoint-isomorphism coincides with principal isotopism; hence, nonassociative division rings can be studied within this framework. This also corrects an error in an earlier pre-print; see Remark 2.11

The Effectiveness of Juvenile Correctional Facilities: Public Versus Private Management

Abstract This paper uses data on juvenile offenders released from correctional facilities in Florida to explore the effects of facility management type (private for-profit, private nonprofit, public state-operated, and public county-operated) on recidivism outcomes and costs. The data provide detailed information on individual characteristics, criminal and correctional histories, judge-assigned restrictiveness levels, and home zip codesallowing us to control for the nonrandom assignment of individuals to facilities far better than any previous study. Relative to all other management types, for-profit management leads to a statistically significant increase in recidivism, but relative to nonprofit and state-operated facilities, for-profit facilities operate at a lower cost to the government per comparable individual released. Cost-benefit analysis implies that the short-run savings offered by for-profit over nonprofit management are negated in the long run due to increased recidivism rates, even if one measures the benefits of reducing criminal activity as only the avoided costs of additional confinement