Resource Flexibility Issues in Multistage Manufacturing

We test the situational impact of two types of resource flexibility, machine flexibility and labor flexibility, in a material requirements planning (MRP)-driven production system. Machine flexibility has not been treated in prior multistage research, only labor flexibility. Machine flexibility is closely related to a plant's positioning strategy. A process-focused plant opts for considerable machine flexibility by choosing general-purpose equipment. Resource flexibility, if effective, can be an attractive alternative to two other types of buffers, inflated inventories and costly capacity cushions. Our simulation results, using factor settings established earlier by a panel of managers, show that resource flexibility is indeed an effective buffer against uncertainties such as end-item demand variability, capacity bottlenecks, equipment failures, and yield losses. Machine flexibility is especially helpful in environments characterized by high uncertainties, tight capacities, and large lot sizes. Worker flexibility has a similar, but less dramatic, impact. Benefits are most striking with customer service, rather than with inventory or labor productivity. Finally, we show that simultaneous introduction of both machine and labor flexibility yields only marginal improvements over either kind of flexibility alone.     

Parent Psychological Distress: A Moderator of Behavioral Health Intervention Outcomes among Justice‐Involved Adolescents

We examined whether pre‐existing parent psychological distress moderated juvenile offenders’ substance use, sexual risk, and mental health outcomes in a randomized trial. Forty‐seven parent–adolescent dyads received either Family‐based Affect Management Intervention (FAMI) for adolescent substance use and HIV prevention or adolescent‐only Health Promotion Intervention (HPI). Parents’ self‐reported distress at baseline significantly moderated adolescents’ self‐reported marijuana use and alcohol use but not other outcomes at 3 months postintervention, producing crossover interactions. FAMI outperformed HPI when parents reported high‐level distress, whereas HPI outperformed FAMI when parents reported low‐level distress. This finding that the relative efficacy of interventions depends on the severity of parent psychological distress could inform efforts to match substance‐using, justice‐involved adolescents with the intervention most likely to benefit them.     

Building a culture of learning through organizational development: the experiences of the Marin County Health and Human Services Department

After determining a need for organizational change informed by changes in workforce demographics, community demographics, the socio-political and economic environment, and constraints on resources, one agency sought to transform its organizational culture into that of a learning organization. An external organizational development consultant was hired to work with agency leadership to identify ways that would help move the agency's culture towards one that was conducive to learning. Specifically, the agency director sought to create a culture where communication is encouraged both vertically and horizontally, frontline level workers are engaged and their voices heard, cross-departmental problem solving is practiced, innovative ideas are supported, and evidence-informed practice regularly implemented. This case study describes the experiences of this agency and the process taken toward engaging an external consultant and moving towards the development of a culture of learning.     

Mathematical forms of the distribution of the product of two normal variables

This paper finds the mathematical forms of the distribution of the product where x and x follow a bivariate normal distribution In this paper the distribution when PT0 is expressed as an integral, a new, fundamental result. From this general form, six different cases can be distinguished depending on what is known about the parameters and p. The special cases are Aroian $year:1959 and (6) Additionally, we prove that if and as the distribution of the product approaches the Type III distribution. When p=0# Aroian $year:1959 and Aroian and Meeker $year:1977, give tables for various values of 6., 6 . The results in this paper will be used to provide brief tables for p^O in a separate paper     

Revisions of the Fish Invasiveness Screening Kit (FISK) for its Application in Warmer Climatic Zones,with Particular Reference to Peninsular Florida

The initial version (v1) of the Fish Invasiveness Scoring Kit (FISK) was adapted from the Weed Risk Assessment of Pheloung, Williams, and Halloy to assess the potential invasiveness of nonnative freshwater fishes in the United Kingdom. Published applications of FISK v1 have been primarily in temperate‐zone countries (Belgium, Belarus, and Japan), so the specificity of this screening tool to that climatic zone was not noted until attempts were made to apply it in peninsular Florida. To remedy this shortcoming, the questions and guidance notes of FISK v1 were reviewed and revised to improve clarity and extend its applicability to broader climatic regions, resulting in changes to 36 of the 49 questions. In addition, upgrades were made to the software architecture of FISK to improve overall computational speed as well as graphical user interface flexibility and friendliness. We demonstrate the process of screening a fish species using FISK v2 in a realistic management scenario by assessing the Barcoo grunter Scortum barcoo (Terapontidae), a species whose management concerns are related to its potential use for aquaponics in Florida. The FISK v2 screening of Barcoo grunter placed the species into the lower range of medium risk (score = 5), suggesting it is a permissible species for use in Florida under current nonnative species regulations. Screening of the Barcoo grunter illustrates the usefulness of FISK v2 as a proactive tool serving to inform risk management decisions, but the low level of confidence associated with the assessment highlighted a dearth of critical information on this species.     

Lattice path combinatorics for multiple product identities

Lattice paths are enumerated as walks on a lattice under the Delannoy criterion of vertical, horizontal and upward diagonal steps. Delannoy recursions are generalized for arbitrary weights in each of these directions, where the row elements of the Delannoy triangles correspond to lattice paths for all walks at a given length.     

Regional Religions?: Extending the “Semi-involuntary” Thesis of African-American Religious Participation

This research examines religious affiliation and church attendance among African-Americans in three different regions of the United States to evaluate the thesis that the Black church represents a semi-involuntary institution shaped by historical dynamics of segregation in the rural South. We extend the analyses of others who have found the rural South to have distinctive church participation patterns by examining two nationally representative data sets (the 1972–1996 General Social Surveys and the 1984 National Alcohol Study). We explore both level and type of church attendance of African-Americans, and how patterns differ by region. Further, we refine prior analyses by (1) differentiating between members of historically White and conservative churches from those in the black mainline, (2) examining racial segregation, and (3) focusing on the type of church attendance (rather than just overall level). Ordinary Least Squares (OLS) and logistic regression models support the thesis that the rural South exhibits some distinctive patterns that make the semi-involuntary institution notion a useful concept, although patterns not predicted by the thesis are also found. The semi-involuntary thesis is also used to illuminate some church attendance patterns observed outside the rural South.     

Some aspects of the reparametrization of statistical models

Definitions are given for orthogonal parameters in the context of Bayesian inference and likelihood inference. The exact orthogonalizing transformations are derived for both cases, and the connection between the two settings is made precise. These parametrizations simplify the interpretation of likelihood functions and posterior distributions. Further, they make numerical maximization and integration procedures easier to apply. Several applications are studied.