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971.
Daniel A. Ackerberg Kevin Caves Garth Frazer 《Econometrica : journal of the Econometric Society》2015,83(6):2411-2451
This paper examines some of the recent literature on the estimation of production functions. We focus on techniques suggested in two recent papers, Olley and Pakes (1996) and Levinsohn and Petrin (2003). While there are some solid and intuitive identification ideas in these papers, we argue that the techniques can suffer from functional dependence problems. We suggest an alternative approach that is based on the ideas in these papers, but does not suffer from the functional dependence problems and produces consistent estimates under alternative data generating processes for which the original procedures do not. 相似文献
972.
Jeff Shockley Lawrence A. Plummer Aleda V. Roth Lawrence D. Fredendall 《Production and Operations Management》2015,24(3):451-468
This study uses a service operations management (SOM) strategy lens to investigate chain store retailers' strategic design responsiveness (SDR)—a term that captures the degree to which retailers dynamically coordinate investments in human and structural capital with the complexity of their service and product offerings. Labor force and physical capital are respectively used as proxies for investments in human capital and structural capital, whereas gross margins are proxies for product/service offering complexity. Consequently, SDR broadly reflects three salient complementary choices of SOM design strategy. We test the effects of “brick and mortar” chain store retailers' SDR on current and future firm performance using publically available panel data collected from Compustat and the University of Michigan American Customer Satisfaction Index databases for the period 1996–2011. We find that retailers that fail to keep pace with investments in both structural and human capital exhibit short‐term financial benefits, but have worse ongoing operational performance. These findings corroborate the importance of managers strategically maintaining the complementarity of design‐related choices for improving and maintaining business performance. 相似文献
973.
Nicholas G. Hall Joseph Y.‐T. Leung Chung‐Lun Li 《Production and Operations Management》2015,24(8):1248-1265
This study considers a typical scheduling environment that is influenced by the behavioral phenomenon of multitasking. Under multitasking, the processing of a selected job suffers from interruption by other jobs that are available but unfinished. This situation arises in a wide variety of applications; for example, administration, manufacturing, and process and project management. Several classical solution methods for scheduling problems no longer apply in the presence of multitasking. The solvability of any scheduling problem under multitasking is no easier than that of the corresponding classical problem. We develop optimal algorithms for some fundamental and practical single machine scheduling problems with multitasking. For other problems, we show that they are computationally intractable, even though in some cases the corresponding problem in classical scheduling is efficiently solvable. We also study the cost increase and value gained due to multitasking. This analysis informs companies about how much it would be worthwhile to invest in measures to reduce or encourage multitasking. 相似文献
974.
Raymond Fisman Nikolaj A. Harmon Emir Kamenica Inger Munk 《Journal of the European Economic Association》2015,13(5):871-905
Using data on Members of the European Parliament (MEPs), we examine the impact of salaries on the composition and the behavior of legislators. Employing a differences‐in‐differences approach, we exploit the introduction of a law that equalized MEPs' salaries which had previously differed by as much as a factor of 10. Increasing salaries raises the fraction of MEPs who run for re‐election but decreases the quality of elected MEPs (proxied by college quality). Salary has no discernible impact on effort or legislation output. Higher salaries induce more political competition. 相似文献
975.
Nolan A. Wages Alexia Iasonos John O'Quigley Mark R. Conaway 《Pharmaceutical statistics》2020,19(2):137-144
This paper studies the notion of coherence in interval‐based dose‐finding methods. An incoherent decision is either (a) a recommendation to escalate the dose following an observed dose‐limiting toxicity or (b) a recommendation to deescalate the dose following a non–dose‐limiting toxicity. In a simulated example, we illustrate that the Bayesian optimal interval method and the Keyboard method are not coherent. We generated dose‐limiting toxicity outcomes under an assumed set of true probabilities for a trial of n=36 patients in cohorts of size 1, and we counted the number of incoherent dosing decisions that were made throughout this simulated trial. Each of the methods studied resulted in 13/36 (36%) incoherent decisions in the simulated trial. Additionally, for two different target dose‐limiting toxicity rates, 20% and 30%, and a sample size of n=30 patients, we randomly generated 100 dose‐toxicity curves and tabulated the number of incoherent decisions made by each method in 1000 simulated trials under each curve. For each method studied, the probability of incurring at least one incoherent decision during the conduct of a single trial is greater than 75%. Coherency is an important principle in the conduct of dose‐finding trials. Interval‐based methods violate this principle for cohorts of size 1 and require additional modifications to overcome this shortcoming. Researchers need to take a closer look at the dose assignment behavior of interval‐based methods when using them to plan dose‐finding studies. 相似文献
976.
Sharon Varghese A 《统计学通讯:理论与方法》2020,49(12):3026-3043
AbstractIn literature, Lindley distribution is considered as an alternative to exponential distribution to fit lifetime data. In the present work, a Lindley step-stress model with independent causes of failure is proposed. An algorithm to generate random samples from the proposed model under type 1 censoring scheme is developed. Point and interval estimation of the model parameters is carried out using maximum likelihood method and percentile bootstrap approach. To understand the effectiveness of the resulting estimates, numerical illustration is provided based on simulated and real-life data sets. 相似文献
977.
Andressa A. Sleiman Nicholas Matey 《Journal of Organizational Behavior Management》2020,40(1-2):82-92
ABSTRACT Over the years, reviews in behavior analysis have sought to identify the most prolific researchers and institutions. The goal of these reviews was to offer one resource for behavior analysts to identify experts in behavior analysis and quality graduate programs. However, most of these reviews omitted the Journal of Organizational Behavior Management (JOBM), making the results less relevant to those who work in organizational behavior management. The purpose of this review was to extend previous findings and identify the most published researchers, academic institutions, and organizations in JOBM since its inception. Furthermore, we calculated the citation rate (per year, per article) for each of the top 20 most published authors. The results, implications, and opportunities for further analysis are discussed. 相似文献
978.
This paper performs a systematic literature review of the undeniably diverse – and somewhat fragmented – current state of research on the collaborations and internationalization of small and medium‐sized enterprises (SMEs). We analyze key works and synthesize them into a framework that conceptually maps key antecedents, mediators, and moderators that influence the internationalization of SMEs. In addition, we highlight limitations of the literature, most notably in terms of theoretical fragmentation; extant theories are deployed and illustrated but rarely extended in a manner that significantly informs subsequent work. At an applied (but related) level, we argue the need for supplementary work that explores the distinct stages of internationalization – and the scope and scale of this process – rather than assuming closure around particular events. With this, we highlight the need for more rigorous and empirically informed explorations of contextual effects that take account of the consequences of developments in the global economic ecosystem. 相似文献
979.
Over the last five years, scholars from a wide variety of disciplines have problematized the discourse of “adolescent female exceptionalism” (Switzer in Fem Theory 14(3):345–360, 2013, p. 4) popularized by the NIKE Foundation’s Girl Effect. Arriving at similar conclusions, scholars point to the artificial neocolonial divisions between ‘the West’ and ‘the rest’ of the world animated by an ‘invest in girls’ logic. This paper endeavors to move beyond the “oppositional girlhoods” (Bent in Sociol Stud Child Youth 16(1):3–20, 2013a, p. 7) bind of girl effects discourse to propose that differentially positioned and experienced girlhoods might be better understood as transnational, relational cultural formations. Drawing from our empirical research with girls in North America and Sub-Saharan Africa, we consider the implications of girls’ increasing global visibility as the ‘saviors of humanity’ from different geopolitical contexts. We then go further to suggest the oppositional girlhoods frame assumes reductive, apolitical, and ahistorical claims of divergence between girlhoods in the Global North and Global South “with highly unequal effects” (Gonick et al. in Girlhood Stud 2(3):1–9, 2009, p. 3). By countering the normative construction of global girlhoods as mutually exclusive forms of personhood and historical experience, our project authorizes a new understanding of girlhoods as mutually constituted and relationally contingent. It is from within this relational framework that we propose new directions for thinking about girlhoods transnationally. 相似文献
980.
In randomized clinical trials, the log rank test is often used to test the null hypothesis of the equality of treatment-specific survival distributions. In observational studies, however, the ordinary log rank test is no longer guaranteed to be valid. In such studies we must be cautious about potential confounders; that is, the covariates that affect both the treatment assignment and the survival distribution. In this paper, two cases were considered: the first is when it is believed that all the potential confounders are captured in the primary database, and the second case where a substudy is conducted to capture additional confounding covariates. We generalize the augmented inverse probability weighted complete case estimators for treatment-specific survival distribution proposed in Bai et al. (Biometrics 69:830–839, 2013) and develop the log rank type test in both cases. The consistency and double robustness of the proposed test statistics are shown in simulation studies. These statistics are then applied to the data from the observational study that motivated this research. 相似文献