200 research outputs found
Error characterization of the alpha residuals emissivity extraction technique
When dealing with remotely sensed images, a parameter that aids in material identification is its emissivity. By extracting a materials emissivity spectrum, the probability of correctly identifying it greatly increases. The Alpha Residual algorithm was developed for just such a process. The Alpha Residuals emissivity extraction technique was originally developed for six channel Thermal Infrared Multispectral Scanner (TIMS) data. In dealing with TIMS data, it is known that the error at 300K is 1%. In recent years, detector technology has led to sensors with higher spectral resolution and an increased number of bands. The goal of this project is to determine if error is reduced due to increased spectral resolution and to produce an error plot that is temperature dependent. An error characterization algorithm was written in C++ to simulate one pixel in a 128-channel Spatially Enhanced Broadband Array Spectrograph System (SEBASS) image with known output. After the results for this were validated, the algorithm was applied to real data. Spectral response and the number of sample points per channel were shown to contribute to the resulting amount of error. As the number of sample points per channel increased, the error between the two alpha residual spectra decreased. When spectral response width increased, so did the error. When actual image data was used, the error had significant spectral structure, but was still very small. This technique is a pixel by pixel operation and thus, outputs an error spectrum for each pixel
Prospective Prediction of Juvenile Homicide/Attempted Homicide among Early-Onset Juvenile Offenders
While homicide perpetrated by juveniles is a relatively rare occurrence, between 2010 and 2014, approximately 7%–8% of all murders involved a juvenile offender. Unfortunately, few studies have prospectively examined the predictors of homicide offending, with none examining first-time murder among a sample of adjudicated male and female youth. The current study employed data on 5908 juvenile offenders (70% male, 45% Black) first arrested at the age of 12 or younger to prospectively examine predictors of an arrest for homicide/attempted homicide by the age of 18. Among these early-onset offenders, males, Black youth, those living in households with family members with a history of mental illness, those engaging in self-mutilation, and those with elevated levels of anger/aggression (all measured by age 13) were more likely to be arrested for homicide/attempted homicide by age 18. These findings add to the scant scientific literature on the predictors of homicide, and illustrate potential avenues for intervention
Adverse Childhood Experiences Distinguish Violent Juvenile Sexual Offenders’ Victim Typologies
Juvenile perpetrators account for over 25% of all sexual offenses, and over one-third of such offenses are against victims under the age of 18. Given empirical connections between adverse childhood experience (ACE) exposure and perpetration of violence, we create victim typologies based on the juveniles’ relationship to their victims among 5539 justice-involved adolescents who have committed violent against-person sexual felonies. Multinomial logistic regression is used to assess which covariates, including individual ACE exposures and cumulative traumatic exposures, are associated with victim typologies. This approach allows for better targeting of violence prevention efforts, as a more nuanced understanding of the increased likelihood to victimize specific victim groups lends to potential differences in treatment provision, beyond simplistic findings regarding ACE exposure increasing offending. Results indicate five classes of victim types, ranging from a low of 6.4%, with primarily strangers as victims, to 31.3%, with predominately acquaintances as victims, and only 12.9% with a diverse array of relationships to victims. Importantly, many demographic and individual risk factors, and specific traumatic exposures were related to victimizing one’s sibling, while cumulative trauma as measured by an ACE score decreased the likelihood of victimizing classmates, while increasing the likelihood of victimizing siblings and other relatives compared to victimizing acquaintances
Dynamic Risk Trajectories, Community Context, and Juvenile Recidivism
Purpose
While the implementation of risk assessment has expanded, the extent to which there are different trajectories of risk/protective factors among adjudicated youth during supervision in the community remains unanswered. The goal of the current study is to identify the distinct trajectories in dynamic risk and protective factors among youth on probation and assess whether different patterns in risk over time are associated with continued offending.
Method
Group-based trajectory modeling is used to identify distinct trajectories across multiple domains of risk/need. The individual- and neighborhood-level factors associated with these trajectories are then explored, prior to examining their relationship to continued delinquency.
Results
Results suggest that a sizable combination of risk/needs trajectories exist among youth on probation. These distinct trajectories are differentially associated with individual and neighborhood characteristics. A select number of trajectories also appear to be indicative of continued offending post-completion of community supervision.
Conclusions
Information regarding the evolving nature of juvenile risk/needs during supervision is critically important to reduce incarceration, flatten the age-crime curve, and ensure public safety. Findings have implications for the use of dynamic risk assessment among youth on probation as well as juvenile recidivism research more generally
The Effect of Program Staffing Difficulties on Changes in Dynamic Risk and Reoffending among Juvenile Offenders in Residential Placement
Recently there has been growing concern regarding the staffing challenges that plague the U.S. correctional system. This study examines whether staffing challenges within residential facilities are associated with changes in dynamic risk and the likelihood of reoffending among a sample of serious juvenile offenders returning to the community from residential placement. Using administrative data on 2,022 youth who completed a court-imposed placement, in combination with information drawn from a provider’s human resources database, we employ several analytical techniques to untangle the effects of staffing difficulties on youth outcomes. Results indicate that the rate of unscheduled absences was associated with changes in dynamic risk and the duration of placement. Absences were also related to recidivism prior to accounting for changes in dynamic risk and length of stay, suggesting a more complex interrelationship between facility staffing challenges and youth outcomes. Implications for policy and future research are discussed
A Statewide Analysis of the Impact of Restitution and Fees on Juvenile Recidivism in Florida Across Race & Ethnicity
Whether the imposition of monetary sanctions is related to juvenile recidivism is explored overall and across race and ethnicity. Leveraging a statewide sample, logistic regression was used to predict fees and restitution assignment based on youth/case characteristics, hierarchical linear and logistic random-effects regression examined the association between neighborhood characteristics with fees and restitution, and propensity score matching examined whether fees and/or restitution are related to reoffending. No race/ethnic differences were found in the proportion of youth receiving court fees, yet when fees were administered both black and Hispanic youth received higher fees. Neighborhood characteristics have minimal impact on whether (or the amounts) monetary sanctions were assigned. Post-matching, fees increased recidivism, as did being black or Hispanic. Interactions between race/ethnicity and both fees and restitution showed black youth with restitution had a higher recidivism likelihood. Monetary sanctions imposed on youth involved in the juvenile justice system has a potential deleterious impact on recidivism
Adherence to the Street Code Predicts an Earlier Anticipated Death
Objective: Criminologists have long been interested in the relationship between subcultural attitudes and antisocial behavior, with Anderson’s street code thesis being the most recent and often researched foray in this area. Relatedly, scholars have begun to investigate the risk factors associated with the anticipation of early death. Extant research, however, has yet to empirically test Anderson’s hypothesis that subscription to the street code is predictive of an anticipated early death. This study contributes to the literatures on the street code as well as fatalism by investigating the link between these two constructs.
Method: Using data from a sample of serious youthful offenders, we examine whether street code values are related to the anticipation of a short lifespan using a number of multivariate regression techniques controlling for a range of individual- and community-level variables.
Results: Results show adherence to the street code is significantly associated with an anticipated early death among the sample of delinquent youth. Further, the relationship between street code and anticipated early death holds across race/ethnicity and gender, and results are not sensitive to the measurement of an anticipated early death. Findings from the current research are discussed, along with implications for policy and future research
Hostile, quick-tempered, and exposed to dangerous environments: Exploring the link between temperament and street code adherence
Although Elijah Anderson’s (1999) code of the street thesis has received a great deal of scholarly attention, fewer studies have examined the characteristics associated with its adoption. Existing evidence is supportive of Anderson’s initial observations, however, less is known about the association between personality and emotional characteristics and adopting street code norms. The current study assesses the role of Delisi and Vaughn’s difficult temperament index in the adoption of the street code among a sample of juvenile justice-involved youth. Results indicated youth with more difficult temperaments, characterized by lower levels of effortful control and higher levels of negative emotionality, were more likely to report greater street code adherence. Implications for juvenile justice policy and future research are discussed
The maltreatment-violence link: Exploring the role of maltreatment experiences and other individual and social risk factors among young people who offend
Objective: This study investigated the extent to which violent offending in a population of young people detained in secure care facilities is related to variations in child maltreatment after controlling for other known individual and social correlates of crime. Method: Official child protection and youth justice records and survey information for 1819 young people were analyzed. Measures included: maltreatment factors (including type, timing and recurrence); out-of-home care placement factors (including type, age at first placement, stability and duration of placements); social factors (including family and peer risk indicators); and individual factors (including factors relating to intelligence and education, substance use, mental health problems, and behavior). Gender and cultural background were also investigated as potential moderating factors. Logistic regression was used to determine the independent effect of maltreatment factors on violent convictions in the presence of other risk factors. Results: Persistent maltreatment was a consistent predictor of violent convictions. Other independent predictors included: aggression, anger, Indigenous status, and male gender, with household conflict also approaching significance. Conclusion: Collaborative and integrated responses from both child protection and juvenile justice may be needed if comprehensive violence prevention strategies are to be developed for young offenders
Did Juvenile Domestic Violence Offending Change During COVID-19?
The current study adds some of the first light into the initial impacts of the largest global health crisis in a generation on family and domestic violence, the long-term repercussions of which may take decades to unpack. Statewide trends in juvenile arrests for domestic violence (DV)-related offending are examined, taking into account school closures for in-person learning in March 2020 and the subsequent mandate for an in-person learning option in Florida in August 2020. Additionally, trends by sex, race/ethnicity, and severity of the offense are examined. Contrasting with growing studies demonstrating an increase in DV-related arrests among adults, we find a significant decrease upon school closures then subsequent increase when schools reopened with an in-person option. Results held across examined subgroups, yet the extent of increase following mandatory in-person learning availability was not as uniform, with Hispanic youth showing the smallest increase and Black youth the largest. Implications are discussed
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