Research Grants Council Research Articles

Auditing with a Chance of Whistleblowing

This paper investigates the impact of promoting whistleblowing on audit quality and the efficiency of detecting misstatements. On the one hand, whistleblowing alerts the enforcer to the possibility of a misstatement and intensifies the regulatory effort, thereby incentivizing the auditor to improve audit quality. On the other hand, promoting whistleblowing reduces the enforcer’s investigative effort when there is no whistleblowing allegation, which in turn dampens the auditor’s incentive to enhance audit quality. We demonstrate that, under certain conditions, encouraging more whistleblowing can impair audit quality and reduce detection efficiency. We also examine the socially optimal whistleblowing program, and our analysis implies that the optimal whistleblowing intensity is increasing in investment cost and the quality of the whistleblower’s information. This paper was accepted by Ranjani Krishnan, accounting. Funding: C. Tang acknowledges financial support from the Hong Kong Research Grant Council [Project 16503921]. M. Ye thanks the Canadian Social Sciences and Humanities Research Council for funding support [Grant 435-2022-0093]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/mnsc.2024.04808 .

Efficient Frontier and Applications in Product Offering and Pricing

Problem definition: The joint assortment and pricing problem is notoriously difficult to solve, especially for large-scale issues subject to various operational constraints arising from business practices. In this paper, we delve into the joint optimization challenge under constrained logit choice models, accounting for product-differentiated price sensitivities across static, randomized, and dynamic contexts. Methodology/results: We develop a unified optimization methodology that applies efficient frontier and dimensional reduction and transforms the joint optimization problem into a single-variable one with respect to the total choice probability. The efficient frontier is employed to transform the nonconcave objective function equivalently into its concave counterpart. We show that the optimal prices are uniquely determined by the common target adjusted markup. The complexity of the mixed combinatorial optimization problem can be reduced by searching over efficient sets of polynomial size. In the randomized assortment and pricing problem in which the product offer sets and prices follow certain distribution, we show that randomization has the potential to elevate the total revenue to the exact efficient frontier, a feat that the static problem may fail to achieve (with a given total choice probability). For dynamic joint product selection and pricing, we find that the optimal policy adopts a simple time-threshold structure that can be precomputed. Furthermore, we illustrate the robustness of our methodology by extending the analysis to a variety of general settings, including the nested logit model. Managerial implications: The proposed methodology contributes to the increasingly popular topic in retail management by significantly reducing the computational complexity of joint product offering and pricing under different constraints. Our results regarding the effects of product set constraints and price bounds provide valuable insights and guidance to practitioners on product offering and pricing in various business scenarios. Funding: C. Ke acknowledges financial support from the National Natural Science Foundation of China [Grant 72101113]. L. Lu acknowledges financial support from the Hong Kong Research Grants Council [Grants 26501021 and 16502423]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2022.0164 .

Layout Optimization for a Large-Scale Grid-Connected Solar Power Plant

A solar power plant provides green electricity to the public via a power grid. As governments worldwide have pledged to reduce carbon emissions and achieve carbon neutrality, large-scale grid-connected solar power plants are booming. Developing such a plant requires significant investment, a large proportion of which covers construction costs. Such costs, together with the energy yield, critically depend on the plant’s layout. The layout planning of a solar power plant involves a series of complex optimization problems such as district partitioning, photovoltaic (PV) component location, and cable routing problems in a solar power plant. These problems have received limited attention in the literature and are highly challenging because they involve large-scale instances, complex design principles, and complicated physical constraints. Motivated by our collaborative projects with an electrical engineering company in China, this paper specifically focuses on the integrated location and routing (ILR) problem, which involves locating service ways, inverters, combiner boxes, and routing cables to connect them. We develop exact algorithms to effectively solve the ILR problem via a decomposition framework (leading to a variant of Benders decomposition (BD)), which is proven to produce an optimal solution. We also develop an exact branch-and-cut scheme to solve each subproblem in the decomposition framework by incorporating cutting planes and separation algorithms. Our solution approach is evaluated on 50 real-world data instances via extensive numerical experiments. Compared with the manual method based on greedy heuristics used in practice, our approach reduces the total cost by approximately 20%. Our decomposition method also achieves an average gap of 0.02% between the obtained lower and upper bounds, significantly smaller than the 16.08% gap achieved with the traditional BD. History: Accepted by Alice E. Smith and David Alderson, Area Editors for Network Optimization: Algorithms & Applications. Funding: This work was partially supported by the Research Grants Council of Hong Kong [Grant 15501221], the National Natural Science Foundation Program of China [Grants 72122006, 72471100, and 72131008], Huazhong University of Science and Technology Double First-Class Funds for Humanities and Social Sciences (Digital Intelligence Decision Optimization Innovation Team), the Interdisciplinary Research Program of HUST [Grant 5003300129], and the Fundamental Research Funds for the Central Universities [Grant 2023WKFZZX101]. Supplemental Material: The software that supports the findings of this study is available within the paper and its Supplemental Information ( https://pubsonline.informs.org/doi/suppl/10.1287/ijoc.2023.0223 ) as well as from the IJOC GitHub software repository ( https://github.com/INFORMSJoC/2023.0223 ). The complete IJOC Software and Data Repository is available at https://informsjoc.github.io/ .

Estimating Demand with Unobserved No-Purchases on Revenue-Managed Data

Problem definition: This paper studies the joint estimation of the consumer arrival rate and choice model parameters when “no-purchasers” (customers who considered the product but did not purchase) are not observable. Estimating this unconstrained demand even with the simplest discrete-choice model such as the multinomial logit (MNL) becomes challenging as we do not know the fraction that have chosen the outside option (i.e., not purchased). Methods have been proposed to use market share to pin down the parameter associated with the outside option. However, market share data are difficult to obtain in many situations, and in some industries, such as fashion retail, have little meaning as the items are difficult to compare. In this paper, we point out an additional difficulty that can arise in practice: Many firms monitor sales and optimize their prices and assortments within the sale period as part of their revenue management (RM) process, based on partially observed demand. This can potentially cause a revenue management induced endogeneity as the data used for estimation is the result of optimization (in turn based on prior data) to set controls. As we demonstrate, methods that work well on randomly generated assortments may do badly on optimized assortment data. Methodology/results: In this paper, we propose a robust method when the firm cannot observe no-purchases and has no market share information, and the data have been revenue-managed. We develop a two-step generalized method-of-moments (GMM) procedure that is based on a modified moment condition, and importantly, does not require instrumental variables (IVs), a significant advantage in practice. Managerial implications: In Monte Carlo simulations, the performance of our method matches existing methods when the controls are generated randomly, and is robust under all conditions, whether RM-induced endogeneity is present or not. On a large real-world data set from the fashion industry, subject to stock-outs and markdown pricing along with unknown management controls, our method provides robust estimates compared with existing methods without requiring any input on market shares, which is especially difficult to pin down at a category and season/collection level. Funding: This work was supported by the Hong Kong Research Grants Council’s General Research Fund [Grant 14506423]. Supplemental Material: The online appendices are available at https://doi.org/10.1287/msom.2021.0291 .

A Data-Driven Optimization Framework for Static Rebalancing Operations in Bike Sharing Systems

Bike sharing systems have been widely deployed in urban cities for first- and last-mile transportation. However, because of the geographical and temporal imbalance of bike demand, bikes need to be reallocated system-wide among stations during the night to maintain a high service level while minimizing demand loss due to stockout or overcapacity. Two technical challenges remain in optimizing the static bike rebalancing operations. One challenge is to accurately predict bike pickup and dropoff demand at each station, considering demand substitution effects and subsequently determining the optimal rebalancing quantity for each station. The other is to efficiently optimize the routing of multiple rebalancing vehicles for large-scale bike sharing systems, considering outlier stations with rebalancing quantities exceeding vehicle capacity. To this end, we propose an end-to-end solution to tackle the aforesaid challenges. Specifically, we first develop deep learning-based predictors that capture the time dependencies of station-level demand, the impact of weather conditions, and the demand substitution effect by nearby stations. Based on the demand rate, a sequential simulation-based demand loss estimator is developed to find the optimal rebalancing quantities that lead to the minimum expected demand loss. Then, a mixed integer linear programming model is formulated to optimize the routing problem of rebalancing vehicles. To address the computational challenge, we propose a data-driven decomposition algorithm to support a multivehicle multivisit rebalancing strategy by decomposing the multivehicle routing problem into smaller and tractable single-vehicle routing problems, which can be solved in parallel. Finally, extensive numerical experiments using real-world data from New York City Citi Bike demonstrate the accuracy of the proposed bike demand predictors, the impact of demand substitution, and the efficiency of the data-driven optimization framework. History: Accepted by Ram Ramesh, Area Editor for Data Science & Machine Learning. Funding: This work was supported by the National Natural Science Foundation of China [Grant 72201222] and the Hong Kong Research Grants Council [Grants CityU 21500220 and CityU 11504322]. Supplemental Material: The software that supports the findings of this study is available within the paper and its Supplemental Information ( https://pubsonline.informs.org/doi/suppl/10.1287/ijoc.2022.0182 ) as well as from the IJOC GitHub software repository ( https://github.com/INFORMSJoC/2022.0182 ). The complete IJOC Software and Data Repository is available at https://informsjoc.github.io/ .

A Squared Smoothing Newton Method for Semidefinite Programming

This paper proposes a squared smoothing Newton method via the Huber smoothing function for solving semidefinite programming problems (SDPs). We first study the fundamental properties of the matrix-valued mapping defined upon the Huber function. Using these results and existing ones in the literature, we then conduct rigorous convergence analysis and establish convergence properties for the proposed algorithm. In particular, we show that the proposed method is well-defined and admits global convergence. Moreover, under suitable regularity conditions, that is, the primal and dual constraint nondegenerate conditions, the proposed method is shown to have a super-linear convergence rate. To evaluate the practical performance of the algorithm, we conduct extensive numerical experiments for solving various classes of SDPs. Comparison with the state-of-the-art SDP solvers demonstrates that our method is also efficient for computing accurate solutions of SDPs. Funding: The research of D. Sun was supported in part by the Hong Kong Research Grants Council under Grant 15307523, and the research of K.-C. Toh was supported by the Ministry of Education, Singapore, under its Academic Research Fund Tier 3 grant call [MOE-2019-T3-1-010].

Optimal Control of Service Systems with Heterogeneous Servers and Priority Customers

We study service systems with parallel servers and random customer arrivals and focus on the waiting cost of customers. Using a Markov decision process (MDP) modeling approach, we analytically characterize the structures of the optimal dynamic server assignment policies for two important systems, one consisting of multiple homogeneous servers and two classes of customers and the other consisting of two heterogeneous servers and multiple classes of customers. Based on the obtained results, we propose a threshold-type heuristic policy for the generalized system consisting of multiple heterogeneous servers and multiple classes of customers. To design such a heuristic policy, we first develop techniques for the performance evaluation of general threshold-type policies with any given threshold values. We then construct a path to search for the optimal threshold values. We compare the performance of the best threshold-type heuristic policy with that of the optimal policy and show that our proposed heuristic policy is computationally efficient yet generates great performance. To derive additional managerial insights, we compare the system under our threshold-type dynamic server assignment policy with other commonly seen and simple systems, such as the dedicated system and the work-conserving flexible priority system. The clear performance advantage observed from extensive numerical experiments demonstrates the importance and usefulness of dynamic server assignment control for systems serving multiple classes of customer arrivals. Finally, we extend our analysis to incorporate customer-dependent service rates and sojourn-time minimization performance metrics. This paper was accepted by Chung Piaw Teo, optimization. Funding: This work was supported by the Hong Kong Research Grants Council [16500921, 16505819] and the National Natural Science Foundation of China [72201233, 72301222]. Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2023.01228 .

Emergency Care Efficiency vs. Quality: Uncovering Hidden Consequences of Fast-Track Routing Decisions

Problem definition: This work aims to examine the role of emergency department (ED) operational status related to congestion in fast-track (FT) routing decisions and the subsequent effects on patient outcomes. Methodology/results: In this paper, we utilize a two-year data set from two hospital EDs in Alberta, Canada, and adopt an instrumental variable approach to examine the effects of FT routing decisions on patient outcomes. Based on the empirical findings, we utilize a data-calibrated simulation to compare the performance of different routing policies. First, our study reveals that FT routing decisions are not purely clinically driven, and ED operational status is also associated with FT routing decisions. Second, being routed to FT can improve ED efficiency by reducing the average length of stay and left without being seen rates. However, this efficiency improvement comes at the cost of potential quality decline. In particular, being routed to the FT leads to an 8.2% increase in the 48-hour revisit rate for the high-complexity group and a 2.3% increase for the medium-complexity group. Third, we delve into the mechanisms behind observed patient outcomes and find that physicians in the FT area may prioritize expediting patient flow by simplifying patient diagnosis and treatment procedures. Consequently, the quality of care may be compromised for high- and medium-complexity patients. Finally, our simulation findings highlight the importance of selecting the “right” patients to be routed to the FT unit. To this end, the complexity-based classification method and dynamic routing policies emerge as promising avenues. Managerial implications: Our findings call for immediate attention from healthcare practitioners to carefully balance the trade-off between emergency care efficiency and quality, emphasizing the necessity of selecting the right patients for routing. Funding: This study is partially supported by the Hong Kong Research Grants Council [Grants GRF 11508921 and CRF C7162-20G]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2022.0440 .

Indirect Value of Public Infrastructure Technology

Although prior research has primarily focused on the direct value of information technology (IT) and IT adoption by individuals and firms, this study explores the indirect value of IT in the form of public infrastructure technology. By exploiting a spatial discontinuity in water monitoring stations, we discover that firms located immediately upstream of water monitoring stations exhibit significantly lower levels of corruption than firms located immediately downstream. These findings are particularly noteworthy given that water monitoring stations have the potential to generate significant indirect value as they are not explicitly designed to mitigate corruption. Further analyses reveal that public infrastructure technology alone does not hold the key to mitigating corporate corruption. Instead, it is the synergistic interplay between public infrastructure technology and organizational change that drives the outcome. These findings contribute to a deeper understanding of the broader IT value landscape, emphasizing the indirect value of technological advancements in public infrastructure that were not originally intended for such benefit. Additionally, our findings highlight the benefits of leveraging existing infrastructure technology to address emerging societal needs. This paper was accepted by D. J. Wu, information systems. Funding: J. Liu acknowledges financial support from the National Natural Science Foundation of China [Grant 72402127], Shanghai Pujiang Program [Grant 23PJC059] and the Chenguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission [Grant 23CGA10]. S. Pei acknowledges financial support from the National Natural Science Foundation of China [Grant 72302139]. X. (M.) Zhang acknowledges financial support from the Hong Kong Research Grants Council [Grants GRF 14500521, GRF 14501320, GRF 165052947, and TRS:T31-604/18-N]. Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2021.01145 .

Director Liability Protection and the Quality of Independent Directors

We study whether legal liability protection helps companies to recruit and retain high-quality independent directors. We conduct difference-in-differences analyses exploiting the 1999 Ninth Circuit Court of Appeals Ruling on the Silicon Graphics case, which substantially raised the bar for filing securities class action (SCA) lawsuits as a shock. We document supporting evidence for the talent attraction hypothesis by showing improvements in newly recruited independent director quality following the ruling, but only for candidates who are previously not exposed to SCA litigation risk. The effects are stronger for firms facing greater litigation risk ex ante or smaller local supplies of director candidates. Results are more evident for experience-based quality dimensions. We also analyze a sample of voluntary independent director departures and find little support for the talent retention hypothesis, suggesting that more complex factors enter into a director’s continuation decision once a director is already exposed to SCA litigation risk. A policy implication is that liability protection can be useful in attracting more unexposed high-quality candidates to the pool of public boards but does little to attract high-quality candidates who are already in the pool of public firms. This paper was accepted by Gustavo Manso, finance. Funding: H. Zou acknowledges the financial support from a competitive General Research Fund (GRF) grant from the Research Grants Council of the Hong Kong Special Administrative Region, China [Project No. HKU 17513816]. S. Shen acknowledges the financial support from the National Natural Science Foundation of China [Grants 72202164 and 72332003]. The work was partially carried out while R. W. Masulis visited the University of Hong Kong as an FBE visiting researcher, and he thanks the Faculty of Business and Economics of the University of Hong Kong for its sponsorship. Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2020.03743 .

Association of nirmatrelvir–ritonavir with post-acute sequelae and mortality among patients who are immunocompromised with COVID-19 in Hong Kong: a retrospective cohort study

The effect of nirmatrelvir-ritonavir on post-COVID-19 outcomes for individuals who are immunocompromised is understudied. We aimed to examine the association of nirmatrelvir-ritonavir with post-acute sequelae and mortality among patients who are immunocompromised and admitted to hospital with COVID-19. We did a retrospective cohort study using territory-wide electronic health records from the Hong Kong Hospital Authority and Hong Kong Department of Health. Eligible patients were adults aged 18 years or older who tested positive for SARS-CoV-2 during the study period (March 11, 2022, to Nov 9, 2023) and were admitted to hospital with COVID-19. Four exposure groups were formed based on immune status (immunocompromised or immunocompetent) and nirmatrelvir-ritonavir status (yes or no). The primary outcome was post-acute inpatient death, starting from 21 days after the positive RT-PCR date. Standardised mortality ratio weighting with doubly robust adjustment was applied to control for confounders. Cox models were used to estimate hazard ratios (HRs) for the outcomes. Between March 11, 2022, and Nov 9, 2023, there were 89 772 individuals with positive RT-PCR tests, of whom 39 923 met eligibility criteria and were included in the study cohort. 19 914 (49·9%) of 39 923 patients were female, 20 009 (50·1%) were male and the median age was 75·0 years (IQR 63·0-85·0). 846 (38·2%) of 2217 patients who were immunocompromised and 14 586 (38·7%) of 37 706 patients who were immunocompetent were prescribed nirmatrelvir-ritonavir. Among the patients who were immunocompromised, those patients who received nirmatrelvir-ritonavir had significantly lower risk of post-acute inpatient death (HR 0·58, 95% CI 0·45-0·74; p<0·0001) and hospitalisation for acute respiratory distress syndrome (0·43, 0·20-0·90; p=0·024) than those who did not. A significant negative interaction was found between immune status and nirmatrelvir-ritonavir on post-acute all-cause hospitalisation (relative excess risk due to interaction -0·84, 95% CI -1·30 to -0·37; p=0·0004). Nirmatrelvir-ritonavir was associated with reduced risk of post-acute inpatient death among patients who were immunocompromised and admitted to hospital with COVID-19. However, the effectiveness of nirmatrelvir-ritonavir on post-acute hospitalisation outcomes was less pronounced in patients who were immunocompromised than in patients who were immunocompetent. Health and Medical Research Fund, Research Grants Council theme-based research schemes, and Research Grants Council Collaborative Research Fund.

Auditor Skill Demands and Audit Quality: Evidence from Job Postings

This study empirically examines the relation between audit quality and auditors’ cognitive and social skills. Using a novel data set of online job postings by accounting firms, we document substantial variation in the stated demand for auditors’ cognitive and social skills, suggesting that audit offices are not homogeneous in their preferences for such skills. We find a positive relation between audit quality and the prevalence of cognitive and social skills within an audit office’s job postings. This association is stronger for audit engagements that are more complex or require greater coordination, suggesting that cognitive and social skills are particularly important in engagements where effective communication and knowledge transfer, as well as sound professional judgment and skepticism, are needed. The association is also stronger for audit offices with greater investments in new technology, consistent with the complementary relation between cognitive and social skills and the use of technology. Overall, our study offers empirical evidence linking specific auditor skills to audit quality. This paper was accepted by Suraj Srinivasan, accounting. Funding: C. Ham acknowledges financial support from the Blanche “Peg” Philpott Faculty Fellowship. R. N. Hann acknowledges financial support from KPMG. W. Wang acknowledges the financial support from the Hong Kong Research Grant Council [Grant 11503720]. Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2022.01640 .

Intraconsumer Price Discrimination with Credit Refund Policies

Consumers often receive a full or partial refund for product returns or service cancellations. Much of the existing literature studies cash refunds, where consumers get the money back minus a fee upon a product return or service cancellation. However, not all refunds are issued in cash. Sometimes consumers receive credit that can be used for future purchases, oftentimes with an expiration term after which the credit is forfeited. We study the optimal design of credit refund policies. Different from models that consider cash refunds, we explicitly model repeated interactions between the seller and consumers over time. We assume that consumers’ valuation for the product/service varies over time and that there is an exogenous probability for product returns. Several interesting results emerge. First, a credit refund policy facilitates intraconsumer price discrimination for a single type of consumers with stochastic valuation. Second, an optimal policy often involves an intermediate credit expiration term, under which a consumer with a high product valuation always makes a purchase, whereas a consumer with a low product valuation may be induced to make a purchase as the credit approaches expiration, leading to a demand induction effect. Finally, a credit refund policy can be more profitable than a cash refund policy and can lead to a win-win outcome for both the firm and consumers under certain conditions. We also consider several extensions to check the robustness of our findings. This paper was accepted by Jeannette Song, operations management. Funding: Y. Liu was substantially supported by a grant from the Research Grants Council of the Hong Kong Special Administrative Region, China (Project No. PolyU15502420). Y. Liu was also supported by a grant from NSFC [72293564/72293560]. Supplemental Material: The data and online appendices are available at https://doi.org/10.1287/mnsc.2020.03042 .

The Allocation of Talent and Financial Development, 1897 to 1936

We examine how the supply of talent affected financial development based on an experiment that abruptly changed the allocation of talent in historical China. Under the meritocratic civil examination system, government service was the main employment for the Chinese intellectuals. The abolition of this system in 1905 reduced the status and wealth attached to government service, which led the intellectuals to turn to modern banking as a high-status sector of employment. We find that regions where there were more candidates for the civil examination produced more financial professionals after 1905, which translated to a greater development of modern banking. This paper was accepted by Lin William Cong, finance. Funding: C. Lin and C. Ma acknowledge the Research Grants Council of Hong Kong [Grant AoE/B-704/22-R], Y. Sun acknowledges the Young Scientists Fund of the National Natural Science Foundation of China [Grant 72203037] and the Fundamental Research Funds for the Central Universities in UIBE [Grant 20QD14; CXTD12-01], and Y. Xu acknowledges the Young Scientists Fund of the National Natural Science Foundation of China [Grant 72203013] for financial support. Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2023.00456 .

Colonial Legacy and Informal Finance

An influential line of research emphasizes that colonial legacy plays a key role in formal financial development. Can colonial legacy also shape informal finance? We investigate the impact of colonial legacy on informal financial development using a manually georeferenced data set within a credible empirical framework. In the 19th century, Europeans arbitrarily designed colonial borders that partitioned many ethnicities across multiple countries in Africa. Leveraging several spatial regression discontinuity designs across national borders and within British-French–partitioned Cameroon and a unique natural experiment where the same former British colony is compared with two otherwise similar areas with different exposures to French colonization, we discover that former British colonies today have better informal financial development than former French colonies. Exploring the channels, we find that places with a British colonial legacy maintain a style of social control that facilitates information flow, supports private enforcement and market interactions, and promotes strong legal cultures. This paper was accepted by Kay Giesecke, finance. Funding: C. Lin acknowledges the Research Grants Council of Hong Kong for financial support [Grant AoE/B-704/22-R]. J. An acknowledges the general financial support from The University of Hong Kong Start-up Fund for New Professoriate Staff. M. Tai acknowledges the Research Grants Council of Hong Kong for financial support [General Research Fund No. 17500722]. Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2023.01856 .

Social Learning and Content Quality Under Polarization

Problem definition: This paper studies how polarization influences content consumption and production on digital platforms that monetize consumer engagement. Specifically, we consider a content that advocates a particular position on a divisive issue. Consumers with polarized preferences toward the content’s position are sequentially exposed to the content. Initially, consumers are uncertain about the content quality, but they have the opportunity to learn about it using aggregate consumption metrics and other informative signals provided by the platform. Methodology/results: Using a stylized model, we find that under polarization, social learning based on consumption metrics can mislead consumers to perceive low-quality content as higher quality, even in the long run. Consequently, content providers may decrease their effort to improve content quality. These effects are amplified for more polarizing issues, especially when the content’s position is “mainstream” (i.e., aligned with the majority of the population). Our results thus provide a potential explanation for the proliferation of low-quality, polarizing content on platforms. Managerial implications: We offer normative guidance for content platforms seeking to enhance content quality, including offering consumers information to aid the social learning mechanism and appropriately selecting audience to mitigate the echo-chamber effect. Additionally, we propose payment schemes based on content popularity as an effective means to encourage content providers to improve quality. Funding: This work was supported by the Hong Kong Research Grants Council [General Research Fund 16502920]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2022.0533 .

Aqueous Polysulfide-Based Redox Flow Battery with Soluble Molecular Catalysts

Aqueous polysulfide-based redox flow batteries (RFBs) are promising for large-scale energy storage applications due to their low cost and high safety1. However, polysulfide negolyte suffers from poor kinetics, resulting in low operating current density and low energy efficiency2-5. Herein, we proposed a molecular catalyst strategy to transfer the sluggish electrochemical polysulfide reduction reaction to a fast chemical reaction via homogeneous catalysis. Inspired by the electron transport chain in the respiratory process, we selected riboflavin sodium phosphate (FMN-Na) as the molecular catalyst to transfer electrons from electrode to polysulfide with the disulfide bond cleavage6. The reaction rate (or turnover frequency) kobs is determined to be 33 s–1 at 1 M K2S4 solution, and this spontaneous chemical electron transfer process is verified by ultraviolet-visible light spectroscopy. In the polysulfide-ferrocyanide (S-Fe) RFB, the overpotential is dramatically decreased from over 800 mV to 241 mV at 30 mA cm–2 with the assistance of FMN-Na as the molecular catalysts. The catalyzed S-Fe RFB and polysulfide-iodide RFB showed stable operation for over 1,000 cycles at 40 mA cm–2. This work offers a simple but effective method to resolve the bottleneck for aqueous polysulfide-based RFBs, and such a homogeneous catalysis strategy may shed light on other flow battery systems with poor kinetics. We will combine operando spectroscopic techniques and theoretical calculation to discuss the possible reaction mechanism and intermediate.AcknowledgmentThis work is supported by two grants from the Research Grants Council (RGC) T23-713/22-R and RFS2223-4S03. Reference Y. Yao, J. Lei, Y. Shi, F. Ai and Y.-C. Lu, Nat. Energy, 2021, 6, 582-588. Z. Li and Y.-C. Lu, Nat. Energy, 2021, 6, 517-528. X. Wei, G.-G. Xia, B. Kirby, E. Thomsen, B. Li, Z. Nie, G. G. Graff, J. Liu, V. Sprenkle and W. Wang, J. Electrochem. Soc., 2015, 163, A5150. Z. Li, M. S. Pan, L. Su, P.-C. Tsai, A. F. Badel, J. M. Valle, S. L. Eiler, K. Xiang, F. R. Brushett and Y.-M. Chiang, Joule, 2017, 1, 306-327. J. Lei, Y. Yao, Y. Huang and Y.-C. Lu, ACS Energy Lett., 2023, 8, 429-435. J. Lei, Y. Zhang, Y. Yao, Y. Shi, K. L. Leung, J. Fan and Y.-C. Lu, Nat. Energy, 2023, DOI: 10.1038/s41560-023-01370-0.

2272 Methodological challenges and strategies in understanding the lived experiences of childless Chinese older couples

Abstract Introduction With more cases of delayed marriage, voluntary childlessness and infertility among Chinese, childless older couples are anticipated to increase. Although evidence suggests that being childless in Western societies may benefit older couples, older Chinese couples without children are marginalised as no one is available to take care of their physical, psychosocial and financial burdens because children in the Chinese societies are often responsible for caring and supporting older individuals. This ongoing study explores the lived experiences of ageing among childless Chinese older couples. While the research methods are novel in the literature, this study highlights the methodological challenges encountered by the researchers. Method This qualitative study adopts the interpretive phenomenological approach with photovoice. Twenty childless older couples are recruited to participate in two face-to-face interviews and submit photos before the second interview. The photos convey contextual details that are challenging to express in words, thereby enhancing the richness of the interview data. Data are analysed using the van Manen’s thematic analysis and Oliffe’s photographic analysis. Results Some challenges experienced so far include difficulties in recruiting participants, as certain spouses refuse to participate while their partners choose to do so. Also, certain couples are reluctant to talk about dying as the last stage of their ageing or be interviewed simultaneously. Similarly, certain couples may not know how to take and submit photos. Strategies utilised include providing simple and clear explanations before the interview, allowing some couples to be interviewed separately, assuring confidentiality in data handling, and recruiting those competent in using smartphones. Conclusion The methodological challenges and related strategies surrounding recruiting older couples and using photovoice provide valuable implications for future researchers. Acknowledgement The work described in this paper was fully supported by a grant from the Research Grants Council of the Hong Kong Special Administrative Region, China (UGC/FDS16/M09/23).

Distributionally Robust Newsvendor Under Stochastic Dominance with a Feature-Based Application

Problem definition: In this paper, we study the newsvendor problem under some distributional ambiguity sets and explore their relations. Additionally, we explore the benefits of implementing this robust solution in the feature-based newsvendor problem. Methodology and results: We propose a new type of discrepancy-based ambiguity set, the JW ambiguity set, and analyze it within the framework of first-order stochastic dominance. We show that the distributionally robust optimization (DRO) problem with this ambiguity set admits a closed-form solution for the newsvendor loss. This result also implies that the newsvendor problem under the well-known infinity-Wasserstein ambiguity set and Lévy ball ambiguity set admit closed-form inventory levels as a by-product. In the application of feature-based newsvendor, we adopt general kernel methods to estimate the conditional demand distribution and apply our proposed DRO solutions to account for the estimation error. Managerial implications: The closed-form solutions enable an efficient computation of optimal inventory levels. In addition, we explore the property of optimal robust inventory levels with respect to the nonrobust version via concepts of perceived critical ratio and mean repulsion. The results of numerical experiments and the case study indicate that the proposed model outperforms other state-of-the-art approaches, particularly in environments where demand is influenced by covariates and difficult to estimate. Funding: X. Li is supported by the Singapore Ministry of Education [Tier 1 Grant 23-0619-P0001, 24-0500-A0001] and National Natural Science Foundation of China [Grant 72331004]. L. Zhang is partially supported by the National Natural Science Foundation of China [Grants 72171156 and 72231002] and the Hong Kong Research Grants Council [Grant 16212419]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2023.0159 .

Penny Wise and Pound Foolish: Does Striving to Meet Earnings Expectations by Manipulating Real Activities Trigger Product Recalls?

We examine whether managers’ activities in striving to reach earnings targets through real earnings manipulation affect their firms’ product recalls. Our evidence implies that firms suspected of manipulating real activities in trying to meet earnings benchmarks exhibit a higher likelihood and frequency of product recalls. In cross-sectional results consistent with expectations, we find that the impact of exploiting real activities to attain earnings benchmarks on product recalls intensifies for firms whose managers have stronger incentives to manage earnings and subsides for firms subject to greater customer power and firms with more growth opportunities. Additional analysis shows that lowering product quality to meet or beat earnings expectations undermines firms’ future performance. This paper was accepted by Ranjani Krishnan, accounting. Funding: Y. Chen acknowledges the General Research Fund of the Research Grants Council of Hong Kong [Project 15504219] for financial support. L. Ma acknowledges financial support from the Ministry of Education Project of Humanities and Social Sciences [Project 22YJC630099] and the Young Scholars Grant Program of the University of International Business and Economics [Project 20YQ06]. Supplemental Material: The online appendix and data files are available at https://doi.org/10.1287/mnsc.2021.04035 .