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3558 items in total found

Journal Articles | 2019

From courts to markets: New evidence on enforcement of pharmaceutical bans in India

Chirantan Chatterjee, Debi Prasad Mohapatra, and Manuel Estay

Social Science & Medicine

Regulatory enforcement of product safety standards given health concerns, whether it is in romaine lettuce, smartphones or cars, is emerging to be a challenge for global public health. This is particularly true for developing economies with fragile institutions. In this context, recent studies on Indian pharmaceutical markets provide evidence suggesting that the sector is a hub for substandard quality of medicines. Departing from these prior studies which use randomly collected samples, we reinvestigate this question using novel pan-India market sales data of banned medicines from 0.75 million pharmacists and chemists in India. We find that indeed such medicines get sold in India even after bans are imposed on them in the period 2007 to 2013. However, there is a general decline in demand post ban for our focal molecules suggesting broad adherence to bans. We also observe regional heterogeneity in prevalence of banned medicines sold between rich and poor regions of India with the former counterintuitively showing more sales. That said, while Ozawa et al. (2018) argue that prevalence of substandard medicines is around 13% in low and middle-income countries, we find an infringement ratio which is more muted in India at about 5%. Finally, a regression-based examination suggests that prior firm presence in therapeutic markets and popularity of molecules positively impact the likelihood of sale of banned medicines in India. Our results are robust to alternative explanations and are substantiated with a theoretical set up examining firm trade-offs in the decision to infringe. India has recently been under the lens of the global access to medicines debate and our findings have important policy implications for global health.

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Journal Articles | 2019

Integrated storage-order picking systems: Technology, performance models, and design insights

ElenaTappiaa, Debjit Roy, MarcoMelacini, and René De Koster

European Journal of Operational Research

In many warehouses shuttle-based technologies have replaced the traditional AS/R system based storage technologies. The impact these systems have on downstream order picking performance is largely unknown. To study the interactions between upstream storage and downstream picking systems, we develop a novel analytical model for integrated storage and order picking systems. The resulting semi-open queuing model is solved using the matrix-geometric method. Using the queuing network model, we are able to study the effect of storage system technology on order throughput times, and the effect of the picking station input buffer size on order picking performance. Further, we analyze the effect of a constant work-in-process (CONWIP) control for orders on system performance. Our results indicate that using SBS/R instead of AS/R-based storage systems yields investment cost savings (i.e., fewer aisles in the storage area and fewer picking stations), paired with a lower total throughput time at a given order arrival rate. Numerical studies show how the total throughput time, first, benefits and then becomes stable by increasing the input buffer size at the picking stations. Retrieving item tote at the storage system in advance with respect to the picker availability is also advantageous, especially in the SBS/R system.

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Journal Articles | 2019

Improving the measurement of school climate using item response theory

Sarah Lindstrom Johnson, Ray E. Reichenberg, Kathan Shukla, Tracy E. Waasdorp, and Catherine P. Bradshaw

Educational Measurement: Issues and Practice

The U.S. government has become increasingly focused on school climate, as recently evidenced by its inclusion as an accountability indicator in the Every Student Succeeds Act. Yet, there remains considerable variability in both conceptualizing and measuring school climate. To better inform the research and practice related to school climate and its measurement, we leveraged item response theory (IRT), a commonly used psychometric approach for the design of achievement assessments, to create a parsimonious measure of school climate that operates across varying individual characteristics. Students (n = 69,513) in 111 secondary schools completed a school climate assessment focused on three domains of climate (i.e., safety, engagement, and environment), as defined by the U.S. Department of Education. Item and test characteristics were estimated using the mirt package in R using unidimensional IRT. Analyses revealed measurement difficulties that resulted in a greater ability to assess less favorable perspectives on school climate. Differential item functioning analyses indicated measurement differences based on student academic success. These findings support the development of a broad measure of school climate but also highlight the importance of work to ensure precision in measuring school climate, particularly when considering use as an accountability measure.

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Journal Articles | 2019

Design, modeling, and analysis of vertical robotic storage and retrieval systems

Debjit Roy, Kaveh Azadeh, and Rene De Koster

Transportation Science

Autonomous vehicle-based storage and retrieval systems are commonly used in many fulfillment centers (e.g., e-commerce warehouses), because they allow a high- and flexible-throughput capacity. In these systems, roaming robots transport loads between a storage location and a workstation. Two main variants exist: horizontal, where the robots only move horizontally and use lifts for vertical transport, and a new variant vertical, where the robots can also travel vertically in the rack. This paper builds a framework to analyze the performance of the vertical system and compare its throughput capacity with the horizontal system. We build closed queueing network models for this that, in turn, are used to optimize the design. The results show that the optimal height-to-width ratio of a vertical system is around one. Because a large number of system robots may lead to blocking and delays, we compare the effects of different robot blocking protocols on the system throughput: robot Recirculation and Wait-on-Spot. The Wait-on-Spot policy produces a higher system throughput when the number of robots in the system is small. However, for a large number of robots in the system, the Recirculation policy dominates the Wait-on-Spot policy. Finally, we compare the operational costs of the vertical and horizontal transport systems. For systems with one load/unload (L/U) point, the vertical system always produces a similar or higher system throughput with a lower operating cost compared with the horizontal system with a discrete lift. It also outperforms the horizontal system with a continuous lift in systems with two L/U points.

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Journal Articles | 2019

Robotized and automated warehouse systems: Review and recent developments

Kaveh Azadeh, Debjit Roy, and Rene De Koster

Transportation Science

Robotic handling systems are increasingly applied in distribution centers. They require little space, provide flexibility in managing varying demand requirements, and are able to work 24/7. This makes them particularly fit for e-commerce operations. This paper reviews new categories of automated and robotic handling systems, such as shuttle-based storage and retrieval systems, shuttle-based compact storage systems, and robotic mobile fulfillment systems. For each system, we categorize the literature in three groups: system analysis, design optimization, and operations planning and control. Our focus is to identify the research issue and operations research modeling methodology adopted to analyze the problem. We find that many new robotic systems and applications have hardly been studied in academic literature, despite their increasing use in practice. Because of unique system features (such as autonomous control, flexible layout, networked and dynamic operation), new models and methods are needed to address the design and operational control challenges for such systems, in particular, for the integration of subsystems. Integrated robotic warehouse systems will form the next category of warehouses. All vital warehouse design, planning, and control logic, such as methods to design layout, storage and order-picking system selection, storage slotting, order batching, picker routing, and picker to order assignment, will have to be revisited for new robotized warehouses.

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Journal Articles | 2019

Strategizing in small informal retailers in India: Home delivery as a strategic practice

Atul Arun Pathak and George Kandathil

Asia Pacific Journal of Management

Small informally organized family-owned grocery retailers—kiranas—are ubiquitous in India and have retained market dominance while facing increasing competition from large formally organized retailers (FORs). Yet, strategy literature has under-explored such informal businesses. We explore kiranas’ distinct strategic practices that give them competitive advantage over FORs, generating kiranas’ sustained market dominance. To explore kiranas’ informal strategizing, grounded theoretic analysis of our multi-year case study suggested the employment of strategy as practice (SAP) framework, enriched with the social exchange theory (SET) concepts of trust and reciprocity. We find that the kiranas’ sustained enactment of strategic practice such as free-of-charge home-delivery significantly depends on contextually rich, reciprocity-based social exchange relationships with customers which evolve through praxes involving continuous exchange of trust. The practice enactment and exchange relationships constitute strategy-practitioner’s emerging dual-identity, which in turn reinforces the practices, generating a self-reinforcing cycle of practice enhancement. Within this cyclic relationship, an inimitable enactment of a strategic practice can be a key source of competitive advantage for informally organized small retail retailers over large FORs. By linking two unconnected prominent approaches to understanding patterns of workplace interactions, namely SAP and SET, the study opens theoretical avenues for exploring strategizing of informal businesses.

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Journal Articles | 2019

Identifying defective network components through restricted group testing

Diptesh Ghosh

OPSEARCH

In this paper, we consider a network of switches in which some of the switches may malfunction. Our aim is to find out efficiently (a) if any of the switches in a network of switches are defective, and (b) if there are defective switches, to identify those switches. We find an optimal solution for the first problem and a heuristic solution to the second, and demonstrate the feasibility of our approach through computational experiments.

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Journal Articles | 2019

Reverse innovation: a conceptual framework

Suresh Malodia, Shaphali Gupta, and Anand Kumar Jaiswal

Journal of the Academy of Marketing Science

Reverse innovation (RI) has emerged as a new growth strategy for MNCs to innovate in emerging markets and then to further exploit the profit potential of such innovations by subsequently introducing them not only in other similar markets but also in developed markets, thereby delivering MNCs a sustainable growth globally. In this study, we propose an overarching conceptual framework to describe factors that contribute to the feasibility of RIs. Using grounded theory with a triangulation approach, we define RI as a multidimensional construct, identify the antecedents of RI, discuss the outcomes, and propose a set of moderating variables contributing to the success of RIs. We also present a set of research propositions with their relative effects on the relationships proposed in the conceptual framework. Additionally, we provide future research directions and discuss theoretical contributions along with managerial implications to realize the strategic goals of RI.

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Journal Articles | 2019

The goblet and two faces: Understanding transcendence and paradox from the perspective of Advaita Vedanta

Shiva Kakkar (FPM)

Human Resource Management International Digest

Purpose

Paradox theory looks at ambidexterity as a set of paradoxical yet interrelated demands. A form of response to such paradoxes is transcendence. Currently, there is limited understanding of the concept among researchers. Using concepts from the Indian philosophy of Advaita Vedanta, this paper aims to provide a deeper understanding of transcendence, highlight some of the epistemological challenges it presents and suggest ways in which the concept can be used by practitioners and ambidexterity researchers.

Design/methodology/approach

The paper uses concepts and theories from advaitic episteme to look at concepts of paradox and transcendence. The method of adhyaropa–apavada is introduced as a way to help individuals get a transcendental perspective of paradoxes. The application of the method is demonstrated using secondary data from published research on ambidexterity management.

Findings

It is postulated that transcendence is an “intuitive experience” born out of reflexive thinking. The dialectic of adhyaropa–apavada (affirmation followed by recension) is suggested as a pedagogical tool that can promote reflexive thinking.

Originality/value

The paper significantly adds to the theoretical understanding of paradoxes and transcendence in ambidexterity literature. The paper also makes a strong pedagogical contribution to literature by suggesting the dialectic of adhyaropa–apavada that can be used by managers to promote reflexive thinking among subordinates when faced with paradoxical situations.

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Journal Articles | 2019

Leveraging service recovery strategies to reduce customer churn in an emerging market

Sourav Bikash Borah, Srinivas Prakhya, and Amalesh Sharma

Journal of the Academy of Marketing Science

Building on the properties of emerging markets, we investigate how a firm should align its service recovery strategies with different types of service failure to reduce customer churn in an emerging market. Using resource exchange theory and a multi-method approach, we show that the conventional wisdom related to service recovery needs to be reevaluated in emerging markets. Our results show that process failures lead to a higher likelihood of customer churn compared to outcome failures in emerging markets. Investigating service recovery mechanisms, we find that compensation is more effective in recovering from process failures than in recovering from outcome failures in emerging markets. Similarly, employee behavior has a stronger impact on mitigating the ill effects of process failures than those of outcome failures. The study contributes to the literature on service recovery and resource exchange theory and provides managerial insights for the effective management of customer churn due to service failures in emerging markets.

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