The age old question, which comes first? A simultaneous test of children's savings and children's college-bound identity

This study has three goals: (1) to provide an extensive review of research on the assets/expectation relationship, (2) to provide a conceptual framework for how children's savings effects children's college-bound identity (children's college expectations are a proxy for children's college-bound identity), and (3) to conduct a simultaneous test of whether owning a savings account leads to college-bound identity or college-bound identity lead to owning a savings account using path analytic technique with Structural Equation Modeling (SEM). Our review reveals asset researchers theorize about college-bound identity in two distinct but compatible ways: college-bound identity as a “linking mechanism”, and college-bound identity as a mediator. However, there has been little theoretical development on the attitudinal effects of assets. In this study, we posit a conceptual framework for how children's savings affects children's college-bound identity. Findings from the simultaneous test of the assets/college-bound identity relationship suggest that savings has modest effect on college-bound identity and vice versa. A policy implication is that asset building policies that seek to build children's college-bound identity in addition to their savings may be more effective than policies that only seek to build children's savings.     

Setups and effective capacity: the impact of lot sizing techniques in an MRP environment

This study investigates how lot sizing techniques influence the profit performance, inventory level, and order lardiness of an assembly job shop controlled by MRP. Four single-level lot sizing techniques are compared by simulation analysis under two levels of master schedule instability and two levels of end item demand. A second analysis investigates the influence of a multilevel lot sizing technique, the generalized constrained-K (GCK) cost modification, on the four single-level techniques at low demand and low nervousness. The analyses reveal a previously unreported phenomenon. Given the same inventory costs, the single-level lot sizing techniques generate substantially different average batch sizes. The lot sizing techniques maintain the following order of increasing average batch size (and decreasing total setup time):

economic order quantity (EOQ)

period order quantity (POQ)

least total cost (LTC)

Silver-Meal heuristic (SML)

The causes for different average batch sizes among the lot sizing techniques are analysed and explained. Demand lumpiness, inherent in multilevel manufacturing systems controlled by MRP, is found to be a major factor. The number of setups each lot sizing technique generates is the primary determinant of profit performance, inventory level, and order tardiness. EOQ, a fixed order quantity technique, is less sensitive to nervousness than the discrete lot sizing techniques. EOQ_, however, generates the smallest average batch size, and, therefore, the most setups. Since setups consume capacity, EOQ, is more sensitive to higher demand. SML generates the largest average batch sizes, and is, therefore, less sensitive to increased demand. At low demand, the other lot sizing techniques perform better on all criteria. They generate smaller batches and, therefore, shorter actual lead times. The GCK cost modification increases the average batch size generated by each lot sizing technique. GCK improves the profit and customer service level of EOQ the lot sizing technique with the smallest batches. GCK causes the other lot sizing techniques to generate excessively large batches and, therefore, excessively long actual lead times.     

Evaluation of a class-based storage scheduling technique applied to dual-shuttle automated storage and retrieval systems

Research to improve the performance of automated storage and retrieval systems has concentrated on developing more effective system designs or scheduling control programs to reduce the time a shuttle spends travelling in a rack. Sarker et al. (1991) showed that a dual-shuttle AS/RS operating under a nearest-neighbour scheduling model would significantly improve system throughput performance over a single-load shuttle system. The study was limited in that it only considered dual-shuttle improvements under the nearest-neighbour model. This research exploits the benefits of a dual-shuttle system by integrating the technology with a more effective scheduling technique, the class-based storage model, for reducing the shuttle travel time. The dual-shuttle, class-based storage model produced a significant reduction in shuttle travel time and thus higher throughput results over the dual-shuttle, nearest-neighbour model. This study further supports the premise that a dual-capacity shuttle is an effective way of improving the productivity of an automated storage and retrieval system.     

Measurement Error and the Effects of Unions on the Compensating Differentials for Fatal Workplace Risks

With essentially the same estimation methods and time period but using different UK data sets and risk measures, Sandy and Elliott (1996) found that nonunion male manual workers had a substantially higher fatal risk premium than union workers while Siebert and Wei (1994) found the opposite. This paper attempts to reconcile these conflicting results using the different measures of fatal risk employed in these two studies together on the same data set. The conflicting results are due to several types of measurement error. We find substantial miscoding in the employee-reported industry affiliation as well as larger errors-in-variables bias in the industry-based risk than in the occupation-based risk.     

Social movement in stages: a reply to Shultziner and Goldberg

This paper is a reply to Doron Shultziner and Sarah Goldberg's article The Stages of Mass Mobilization: Separate Phenomena and Distinct Causal Mechanisms. The article recognizes the theoretical contribution of the study, in particular the re‐introduction of the largely neglected stage approach in social movement studies. It then raises two major concerns related to how the authors narrow their approach to single episodes of mass mobilization and how definitively they distinguish movement stages.     

Obtaining cancer risk factor prevalence estimates in small areas: combining data from two surveys

Summary.  Cancer surveillance research requires accurate estimates of risk factors at the small area level. These risk factors are often obtained from surveys such as the National Health Interview Survey (NHIS) or the Behavioral Risk Factors Surveillance System (BRFSS). The NHIS is a nationally representative, face-to-face survey with a high response rate; however, it cannot produce state or substate estimates of risk factor prevalence because the sample sizes are too small and small area identifiers are unavailable to the public. The BRFSS is a state level telephone survey that excludes non-telephone households and has a lower response rate, but it does provide reasonable sample sizes in all states and many counties and has publicly available small area identifiers (counties). We propose a novel extension of dual-frame estimation using propensity scores that allows the complementary strengths of each survey to compensate for the weakness of the other. We apply this method to obtain 1999–2000 county level estimates of adult male smoking prevalence and mammogram usage rates among females who were 40 years old and older. We consider evidence that these NHIS-adjusted estimates reduce the effects of selection bias and non-telephone coverage in the BRFSS. Data from the Current Population Survey Tobacco Use Supplement are also used to evaluate the performance of this approach. A hybrid estimator that selects one of the two estimators on the basis of the mean-square error is also considered.     

PAID- VERSUS DONATED-MEDIA STRATEGIES FOR PUBLIC SERVICE ANNOUNCEMENT CAMPAIGNS

Public service announcement (PSA) campaigns have traditionallyrelied on donated rather than paid advertising media. Recently,however, both government agencies and charitable or ganizationshave questioned whether donated-media strategies should be abandonedfor paid-media PSA campaigns. The present research examinesthis issue in a three-market field experiment comparing theeffectiveness of "paid versus donated" PSA cam paigns in decreasingyouthful male drinking and driving. Depen dent variables include(1) self-reports of behaviors from sample surveys and (2) officialcounts of incapacitating and fatal highway accidents. Resultsshow that both campaigns were equally effec tive and both werecost efficient. Thus, in light of these results, it is recommendedthat social marketers not abandon donated-media PSA campaignsfor paid-media PSA campaigns.     

MEASURING CRACK COCAINE AND ITS IMPACT

Numerous social indicators turned negative for Blacks in the 1980s and rebounded a decade later. We explore whether crack cocaine explains these patterns. Absent a direct measure, we construct a crack prevalence index using multiple proxies. Our index reproduces spatial and temporal patterns described in ethnographic accounts of the crack epidemic. It explains much of the 1980s rise in Black youth homicide and more moderate increases in adverse birth outcomes. Although our index remains high through the 1990s, crack's deleterious social impact fades. Changes over time in behavior, crack markets, and the user population may have mitigated crack's damaging impacts. (JEL K42, J15, I30)     

Reconciling autonomy and community: the paradoxical role of HRD

This paper examines the competing discourses of autonomy and community, so long a concern to social theorists but which we argue have been under-theorised by researchers of HRD. We argue that it is this tension, embedded in the assumptions and behaviours of those working within organisations, which has informed a growing concern by HRD practitioners to balance the needs of the individual with those of organisations, a preoccupation which dates at least to the appropriation by organisations of the socio-psychological theories of the human relations movement. The paper examines the most recent attempts to reconcile autonomy and community through the emergence of the new managerial discourses of spirituality and organisational citizenship. We conclude that this quest is inevitably elusive, based as it is on assumptions of trust within organisation relationships which are increasingly challenged by the short term nature of our post-bureaucratic organisational relationships and the fragmentation, instability and the blurring of boundaries. We conclude with a call for HRD to take on the mantle of critical educator and moral conscience raiser to encourage a deeper engagement with social, existential and philosophical questions that lie at the heart of organisational life.