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There is interest in stock enhancement to support fisheries for California halibut Paralichthys californicus , a regionally important yet depleted species in the Southern California Bight (SCB), U.S. A quantitative model was developed to assess the cost of increasing harvestable California halibut in the SCB via releases of cultured juveniles. Reduced post-release survival of cultured juveniles was incorporated into the model, as was sex-specific lifetime survival, growth, and maturity. Simulations examined how adult California halibut population metrics were influenced by key release-strategy variables (i.e., size, number, survival, and sex ratio of released juveniles). A target increase in abundance of harvestable (≥ 559 mm total length; TL) California halibut by 5% in the entire SCB could likely be achieved by releasing large numbers (0.1–1.6 million per year) of larger-sized juveniles (40–200 mm TL). However, this was strongly mediated by their survival and sex ratio; fewer and smaller juveniles were required when releases comprised better surviving and / or more female individuals. Depending on the survival and sex ratio of released juveniles, increasing harvestable abundance in the SCB to achieve this 5% target was estimated to cost US$ 0.2–2.9 million annually, or US$ 14–219 per additional harvestable California halibut in the wild. This exploratory modeling study demonstrates that releasing juvenile California halibut could be a feasible management tool in the SCB, and provides a theoretical basis for field experiments. More broadly, it suggests that the allocation of resources to the production of larger and / or better surviving juveniles, in addition to optimizing release sex ratios, should be explored in stock enhancement programs. • Stock enhancement of California halibut was simulated by quantitative modeling. • Pre-defined target was achieved by releasing 0.1–1.6 million larger-sized (40–200 mm) juveniles. • Outcomes were strongly mediated by survival and sex ratio of released fish. • Annual costs to achieve the target were US$ 0.2–2.9 million. • Provides guidance for the allocation of resources in stock enhancement programs. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Illustrate the value of a strategy used for measuring the costs and resources used in the implementation process over and above the costs of the intervention itself in the context of a two-arm randomized controlled trial. Methods: Counties in California and Ohio (sites) were invited to implement Multidimensional Treatment Foster Care (MTFC), an alternative to congregate care for youth. Participating sites (n =53) were randomized to one of two implementation strategies, (1) Community Development Teams (CDT) where sites share information and move through the implementation process as a cohort facilitated by an MTFC purveyor or (2) Individual Implementation (IND: “as usual”) where sites work individually with the MTFC purveyor. The implementations were monitored using the Stages of Implementation Completion (SIC) measure of a number of observable activities, developed as part of the trial to segment the implementation process into 8 stages of implementation. Resource data gathered from the implementation purveyors and site participants were used to map costs onto each of the 8 stages to generate total cost measures stratified by type of resource and stage of implementation for each of the study arms. Results: The SIC provided a feasible costing template to map costs onto observable activities and to enable the examination of important differences in implementation strategies for an evidence-based practice. The average total implementation cost prior to program start-up of CDT was $133,106; IND costs $118,699. While CDT costs more in a number of stages, it resulted in fewer county staff hours being used and shorter mean times to implementation than IND. In cases where rapidity of implementation of reducing staff time required for implementation is valued, then CDT would be the preferable implementation approach. Conclusions: The SIC is a useful tool for determining implementation resources needed for new evidence-based practice programs for youth and particularly for comparing different implementation strategies that might be tried in pilot programs. [Copyright &y& Elsevier]

Abstract: This paper examines the problem of critical infrastructure protection in urban environments and provides a mechanism for evaluating the performance allocated resources on defense of the region. In the devised formulation, a bi-level mixed integer program and hypercube queuing model compose the mathematical model used to represent the concept of critical infrastructure protection between an attacker and a defender operating within the urban environment and an experimental design is used as the basis for observing salient properties and trends. Applying the model within Los Angeles County, California, results demonstrate the trade-offs observed in various protection schemes and illustrate how continuously increasing defense resources does not guarantee a safer region. The implication of detection strategy on response capability is also assessed through the case study, illustrating the importance of balance when deriving solutions. We also show how the mathematical model may be used to support research and development in defense technologies by identifying resource characteristics that strongly influence infrastructure protection. [Copyright &y& Elsevier]

Objective: Analysis of the validity and implementation of a child maltreatment actuarial risk assessment model, the California Family Risk Assessment (CFRA). Questions addressed: (1) Is there evidence of the validity of the CFRA under field operating conditions? (2) Do actuarial risk assessment results influence child welfare workers’ service delivery decisions? (3) How frequently are CFRA risk scores overridden by child welfare workers? (4) Is there any difference in the predictive validity of CFRA risk assessments and clinical risk assessments by child welfare workers? Method: The study analyzes 7,685 child abuse/neglect reports originating in 5 California counties followed prospectively for 2 years to identify further substantiated child abuse/neglect. Measures of model calibration and discrimination were used to assess CFRA validity and compare its accuracy with the accuracy of clinical predictions made by child welfare workers. The extent of use of an override feature of the CFRA and child welfare worker reliance on CFRA risk scores for making service decisions were analyzed. Results: Imperfect but better-than-chance predictive validity was found for the CFRA on a range of measures in a large temporal validation sample (n =6,543). For 114 cases where both CFRA risk assessments and child welfare worker clinical risk assessments were available, the CFRA exhibited evidence of imperfect but better-than-chance predictive validity, while child welfare worker risk assessments were found to be invalid. Child welfare workers overrode CFRA risk assessments in only 114 (1.5%) of 7,685 cases and provided in-home services in statistically significantly larger proportions of higher- versus lower-risk cases, consistent with heavy reliance on the CFRA. Conclusions/practice implications: Until research identifies actuarial models exhibiting superior predictive validity when applied in every-day practice, the CFRA is, and will be a valuable tool for assessing risk in order to make in-home service-provision decisions. [Copyright &y& Elsevier]

Abstract: We examine the impact of teacher professional development on a key aspect of teacher quality—teacher knowledge. Specifically we use English Language Arts teacher content and pedagogy assessments to determine whether the California Professional Development Institutes significantly improve teacher content knowledge and whether teachers retain that knowledge six months after the institutes are completed. The results indicate that teachers vary significantly in pre-institute knowledge on the four assessed domains, that they demonstrate significant knowledge growth between the pre- and post-assessments, but that practical classroom experience hinders knowledge retention as measured six months later. Further, pre-exiting knowledge gaps are not systematically reduced thereby not alleviating the uneven distribution of teacher quality among California elementary schools. [Copyright &y& Elsevier]

Abstract: This paper presents a case study of two California school districts, San Francisco and Oakland, each of which have implemented their own versions of what is popularly known as a weighted student formula (WSF). One primary goal of the WSF policy is to increase the equity with which resources are distributed to schools. With respect to equity, the findings suggest that for particular schooling levels per-pupil spending became more responsive to student poverty and that the increase in responsiveness appears to have coincided with implementation of the WSF in the two districts. Moreover, each district relies on a different mechanism for driving resources to the schools: San Francisco relying to a greater degree on the unrestricted funds, while Oakland relies more heavily on restricted sources which, as directed by law, drive dollars to special need populations. Interestingly, neither district exhibited any significant change in the distribution of teacher experience after implementation of their SBF models; schools serving the highest proportion of students from low-income families continued to employ teachers with the least experience after implementation of the SBF models. While an additional goal of WSF was to drive more resources down to the school level to be spent, our analysis found little substantial change in the proportion of resources expended at the school versus the district level. [Copyright &y& Elsevier]

Abstract: Using data for 108 colleges in the California Community College System, this paper poses two questions. First, do California community colleges differ in their missions? Second, if they do, can inter-college differences in missions be explained? We address the first question by developing college-specific measures of curriculum mix, which we use to characterize colleges as to their curriculum emphases and specializations. We find that colleges differ in the extent to which they offer a transfer specialization or a nontransferable voc-ed specialization. Turning to the second question, we attempt to explain inter-college differences in curriculum emphasis and specialization with institutional variables including student demographics, labor market characteristics, and community characteristics. While not strong, we view our results as suggesting that curriculum emphases and specializations are related to student demographics and community needs. [Copyright &y& Elsevier]