Marginal Problem Research Articles

Effects of diagnostic labels on perceptions of marginal cases of mental ill-health

Two experimental studies (Ns = 261, 684) investigated how diagnostic labels affect perceptions of people experiencing marginal levels of mental ill-health. These effects offer insight into the consequences of diagnostic “concept creep”, in which concepts of mental illness broaden to include less severe phenomena. The studies found consistent evidence that diagnostic labeling increases the perception that people experiencing marginal problems require professional treatment, and some evidence that it increases empathy towards them and support for affording them special allowances at work, school, and home. The studies also indicated that labels may reduce the control people are perceived to have over their problems and their likelihood of recovering from them. These findings point to the potential mixed blessings of broad diagnostic concepts and the cultural trends responsible for them. Expansive concepts may promote help-seeking, empathy, and support, but also undermine perceived agency and expectations that problems can be overcome.

Polygon relations and subadditivity of entropic measures for discrete and continuous multipartite entanglement

In a recent work by us Ge et al [Phys. Rev. A 110, L010402 (2024)], we have derived a series of polygon relations of bipartite entanglement measures that is useful to reveal entanglement properties of discrete, continuous, and even hybrid multipartite quantum systems. In this work, with the information-theoretical measures of Rényi and Tsallis entropies, we study the relationship between the polygon relation and the subadditivity of entropy. In particular, the entropy-polygon relations are derived for pure multi-qubit states and then generalized to multi-mode Gaussian states, by utilizing the known results from the quantum marginal problem. Then the equivalence between the polygon relation and subadditivity is established, in the sense that for all discrete or continuous multipartite states, the polygon relation holds if and only if the underlying entropy is subadditive. As a byproduct, the subadditivity of Rényi and Tsallis entropies is proven for all bipartite Gaussian states. Finally, the difference between polygon relations and monogamy relations is clarified, and generalizations of our results are discussed. Our work provides a better understanding of the rich structure of multipartite states, and hence is expected to be helpful for the study of multipartite entanglement.

Some notes on the basic concepts of support vector machines

Support vector machines (SVMs) are classic binary classification algorithms and have been shown to be a robust and well-behaved technique for classification in many real-world problems. However, there are ambiguities in the basic concepts of SVMs although these ambiguities do not affect the effectiveness of SVMs. Corinna Cortes and Vladimir Vapnik, who presented SVMs in 1995, pointed out that an SVM predicts through a hyperplane with a maximal margin. However existing literatures have two different definitions of the margin. On the other hand, Corinna Cortes and Vladimir Vapnik converted an SVM into an optimization problem that is much easier to solve. Nevertheless, existing papers do not explain how the optimization problem derives from an SVM well. These ambiguities may cause certain troubles in understanding the basic concepts of SVMs. For this purpose, this paper defines a separating hyperplane of a training data set and, hence, an optimal separating hyperplane of the set. The two definitions are reasonable since this paper proves that w0Tx+b0=0 is an optimal separating hyperplane of a training data set when w0 and b0 constitute a solution to the above optimization problem. Some notes on the above margin and optimization problem are given based on the two definitions. These notes should be meaningful for clarifying the basic concepts of SVMs.

Non-cooperative corporate social responsibility, bargaining, and double marginalization in bilateral monopoly

ABSTRACT This study incorporates CSR concerns in a general demand model focusing on the double marginalization problem in single-product successive monopolies. It assumes that the manufacturer or retailer non-cooperatively engages in CSR activities and bargains over the linear input price. The findings demonstrate that the ratio of retail and wholesale pass-through depends not only on the demand curvature and its derivative but also on the firm’s CSR weights and relative bargaining power. In a bilateral monopoly, including CSR considerations by either the manufacturer or the retailer may alleviate the double marginalization problem when bargaining over the linear wholesale price.

Changes in behavioural and emotional well-being of children participating in the Icehearts programme: A feasibility pilot study with 4-year follow-up

BackgroundOrganized sport is shown to be a promising tool for promoting mental health and positive youth development (PYD) among socially vulnerable children and young people. Icehearts is a Finnish sport-based positive youth development programme targeted at children and adolescents with a higher risk of social marginalization and mental health problems. It provides socially vulnerable children with a mentoring relationship that lasts 12 years through childhood and adolescence. ObjectiveThe aim of this study was to investigate the changes in behavioural and emotional well-being of participating children at 4-year follow-up. MethodsData for the feasibility pilot study were collected from parents and teachers of programme participants (n = 65) at baseline (age 7) and at a 4-year follow-up using Strengths and Difficulties Questionnaires. A community sample of peers was used as a reference group (n = 75). ResultsImprovement in prosocial behaviour but no statistically significant changes in different areas of internalising or externalising problems, as assessed by the teachers, were found among programme participants. According to the assessments by the parents, no statistically significant changes among programme participants were found. Among the peers in the reference group, a statistically significant decrease in conduct and emotional problems and an increase in prosocial behaviour were observed. ConclusionThe Icehearts programme may have potential in promoting prosocial behaviour among socially vulnerable children. However, the programme may not be able to reduce emotional and behavioural problems in all children. Further research is needed on how to best support children in need for psychiatric or child welfare services.

Welfare reducing vertical integration in a bilateral monopoly under Nash bargaining

AbstractWe consider a bilateral monopoly where a linear input price is determined by Nash bargaining. We show, with an increasing marginal cost of input production, that vertical integration reduces consumer surplus and welfare compared with bilateral monopoly if the bargaining power of the input supplier is low. This result is important for competition policies as it questions the common wisdom suggesting vertical integration increases welfare by eliminating the problem of double marginalization. Overproduction under bilateral monopoly compared with vertical integration is the reason for our result. Interestingly, consumer surplus and welfare can be higher under a linear input price compared with a two‐part tariff input price.

DEFINING MARGINALIZATION IN CONTEMPORARY SOCIAL CONTEXTS

The work focuses on how marginalization manifests itself in various contexts, including the workplace, education, health and housing, and how it affects various groups of the population, including minorities, women, youth and people with disabilities. The author emphasizes the importance of an intersectoral approach to the problem of marginalization, calling for the integration of the efforts of Government, the private sector, non-governmental organizations and marginalized groups themselves in finding sustainable solutions to overcome exclusion and promote social inclusion and equality. In addition to theoretical analysis, the article contains practical recommendations for the development and implementation of policies and programs aimed at reducing marginalization and its negative consequences. The author emphasizes the need to take into account the diversity of experiences and perspectives of marginalized groups in order to create a more just and inclusive society.

Leveraging the Social Fabric to Improve Rural E-Commerce Access

Motivated by recent developments aimed to address last-mile delivery challenges in rural areas of Indonesia and China, we develop a theoretical model to study how to lower participation barriers to the e-commerce market. We analyze how stage stations lower the cost of last-mile delivery by leveraging the preexisting social fabric in rural communities, including local stores, as well as social technologies such as chat services and virtual groups. Specifically, we examine two models, a decentralized model with stage stations run by independent agents, and a centralized model, similar to the one pioneered by Alibaba Taobao. We find that when the delivery cost in rural areas is high, the decentralized model can lower the participation cost and increase both platform profit and social welfare. In general, the centralized model outperforms the decentralized one. One reason is that the decentralized model suffers from a double marginalization problem. The centralized model has more flexibility, for example, in determining the pricing policies for both sellers and buyers. It could offer free service to rural customers if the participation of fresh rural customers can attract many additional sellers. However, a centralized model may not be feasible in many countries. Therefore, we explore whether the platform can implement a coordination mechanism for decentralized stage stations. We find that our proposed coordination mechanism can improve the performance of the decentralized model. Our results have important implications for how e-commerce platforms can leverage stage stations and social technologies to lower participation barriers for rural customers, thereby creating a more inclusive development model.

CLIMATE CHANGE AND INDUCED MARGINALIZATION: PERSPECTIVES

The global arena of international relations is placing increasing importance on the subject of climate change. The disruptions in natural weather patterns are giving rise to a wide array of challenges in ecological, sociopolitical, and economic systems. This piece of writing investigates the concept of marginalization brought about by the effects of climate change. The analysis adopts a multi-faceted approach, utilizing the framework of climate justice. The primary focus lies in understanding how climate-induced marginalization impacts a nation’s social structure, especially affecting disadvantaged communities. Following that, the conversation delves into making a comparison among different countries, examining their contributions to climate change and the subsequent difficulties they encounter. The article also underscores the insufficiencies in international frameworks aimed at mitigating climate change, underscoring the lack of accountability during their development. Additionally, the problem of climate-induced marginalization is evaluated in the context of the Sustainable Development Goals, and suggestions are put forth to effectively tackle this issue.

Welfare Consequence of Common Ownership in a Vertically Related Market*

We investigate how common ownership affects welfare in a vertically related market. Although common ownership mitigates the double marginalization problem and improves welfare, it restricts competition among downstream firms and harms welfare. We find that whether common ownership is welfare‐improving depends on the degree of competitiveness in the downstream market. Common ownership is more likely to improve welfare when there are fewer downstream firms and a greater degree of product differentiation. In other words, common ownership may improve welfare when competition in the downstream market is weak.

Vertical cross‐ownership, double marginalization, and social welfare

AbstractIn this paper, we study the impacts of cross‐ownership structure on double marginalization problem (DMP) and social welfare under downstream the Bertrand and Cournot competition. We find that in the Bertrand competition, DMP is more serious under backward cross‐ownership than under forward cross‐ownership. Under forward cross‐ownership, because the upstream firm internalizes part of a retailer's profit, it alleviates the DMP. However, for the whole society, forward cross‐ownership is beneficial with respect to backward cross‐ownership. The mark‐up ratio under forward cross‐ownership is the largest, followed by that under vertical separation. The lowest one is under backward cross‐ownership. The results hold under Cournot competition as well.

DIE REZEPTION DER MARGINALITÄT IN DER POSTMODERNEN ÄSTHETIK: PATRICK SÜSKINDS VISION

The purpose of the article is to trace the fictional features of the reception of marginality through the prism of social communication of the main characters in Patrik Süskind`s texts “Der Kontrabass”, “Das Parfüm”, “Die Taube”, “Die Geschichte von Herrn Sommer”. The task is to find out the signs of marginalization of the main characters, to understand their symbolic essence, to determine the triggers that provoked the “borderline” state of a person, and the literary techniques used by the author to reveal the problem of marginality. Historical-literary, cultural-historical, hermeneutic, comparative research methods, sociological approach in the study of marginality were used in this investigation. The concept of “marginality” is interpreted as the presence of an individual in a borderline, peripheral state in relation to other social or professional communities. In the works of Patrick Süskind, within the framework of postmodern aesthetics, a type of marginal hero is invented, and some variations of him are built. The key motif in reproducing the mechanism of marginalization of characters in P. Süskind`s stories is the motif of loneliness in its various manifestations: the seclusion of the hero, his alienation from society, sociophobe. It was found that the image of a marginal hero is not typical, Süskind’s characters are different: the contrabass player is a procrastinator, the perfumer Jean-Baptiste Grenouille is a brilliant criminal, the bank guard Jonathan Noel is a modernized image of a “man in a case”, the eccentric traveler Herr Sommer is a sociophobe. The last literary character is open to the world (three other characters can be described as “recluses”). The image of Grenouille is a simulacrum, and as for other literary characters, readers can find their prototypes in real life. It is emphasized that the author forces readers to look at the problem of marginality in a new way: these are not only scum but also creative people who somehow ended up in the peripheral state of a certain professional or social community. Such creative natures appeared in Süskind’s texts as a contrabass player and a perfumer – in order to clarify the mechanism and features of their marginalization, the author reconstructed the professional environment in the historical context in detail. The author`s reproduction of the specifics of the behavior of marginal heroes is traced: from mental suffering to suicide, with an emphasis on determining the triggers that provoked suicide. The analysis of Süskind’s works shows that the extreme forms of marginalization of literary characters caused the psychological trauma experienced by the characters. The writer is guided by deep knowledge of psychology, in particular, the theory of psychoanalysis, the phenomenon of procrastination, and suicidal behavior. The article decodes the socio-historical background, which is present as a dotted line in each of Patrick Süskind’s stories. They take place in Germany and France in the second half of the 20th century (in the novel “Perfume” – in the French city of the 18th century). Undoubtedly, the author, who is apolitical in the public sphere, consistently condemns the war, Nazism and its manifestations in all his texts. P. Süskind posed to the readers numerous questions relevant to German society: overcoming the legacy of Nazism, for instance, in music, the impact of the Holocaust on the psyche and fate of its victims, re-evaluation of the value system and the role of art in it. Such fictional techniques of postmodernism as the “multilayering” of the texts, their open ending, irony, parody, allusions, the reception of binary oppositions, the motif of energy vampirism, materialism, the blurring of genre boundaries, etc. made it possible to realize author’s ideas.

Enabling joint distribution with blockchain technology in last-mile logistics

Joint distribution is a crucial business model employed to improve courier delivery performance in last-mile logistics (LML). However, the moral hazard of the shared agent related to carrier selection impedes the model’s widespread adoption. Cutting-edge blockchain technology (BT) provides a new way out and allows us to propose a hybrid method by combining coordination contracts with BT. First, we theoretically analyze the behavior of participants in LML. Next, two-part tariff and revenue-sharing contracts are provided to overcome the double marginalization problems in a decentralized business model. Then, BT implementation makes the contracts dynamic and prevents moral hazards during the contract’s execution period. Finally, our method enables trust to be built in the joint distribution even with a relatively loose organizational structure (i.e., courier alliance) with the evidence of the proof-of-concept and numerical experiments. Moreover, the proposed method is highly relevant to the logistics industry and potentially solves a broader array of trust issues in operations and supply chain management.

Quantum space-time marginal problem: global causal structure from local causal information

Spatial and temporal quantum correlations can be unified in the framework of the pseudo-density operators (PDOs), and quantum causality between the involved events in an experiment is encoded in the corresponding PDO. We study the relationship between local causal information and global causal structure. A space-time marginal problem is proposed to infer global causal structures from given marginal causal structures where causal structures are represented by the reduced PDOs; we show that there almost always exists a solution in this case. By imposing the corresponding constraints on this solution set, we could obtain the required solutions for special classes of marginal problems, like a positive semidefinite marginal problem, separable marginal problem, etc. We introduce a space-time entropy and propose a method to determine the global causal structure based on the maximum entropy principle. The notion of quantum pseudo-channel (QPC) is also introduced and we demonstrate that the QPC marginal problem can be solved by transforming it into a PDO marginal problem via the channel-state duality.

Making the invisible visible: stakeholder capitalism and powerless stakeholders

Purpose Stakeholder capitalism has been proposed as an alternative way of thinking about business purpose and value creation. However, stakeholder capitalism can only work as an alternative model of business if all stakeholders and their interests are visible to and taken seriously by managers. The purpose of this paper is to untangle the challenges that invisible, marginalized and powerless stakeholders pose for theorizing about stakeholder capitalism. Design/methodology/approach This paper is conceptual. The authors first briefly outline the promise of stakeholder capitalism for addressing pressing questions about value creation and stakeholder welfare. The authors then conceptualize stakeholder invisibility as the outcome of a particular stakeholder being both powerless and marginal through the prism of moral intensity theory and one of its elements: proximity. This study discusses the ways in which managers can make invisible stakeholders more visible in their decision-making. Findings For managers truly to manage for stakeholders, as anticipated by stakeholder capitalism, all stakeholders and stakeholder interests must be visible to them. This study analyzes why sometimes they are not, how they can be made more visible and why stakeholder visibility matters for stakeholder capitalism. This study proffers three principles for business practice: ethical commitments to reduce stakeholder invisibility, analyses of business strategies to surface the contributions of marginalized and invisible stakeholders and taking rights seriously. Originality/value This study provides a new perspective on stakeholder capitalism by linking the challenge in operationalizing it to the problems of stakeholder invisibility and marginality.

Tapping into Permutation Symmetry for Improved Detection of k-Symmetric Extensions.

Symmetric extensions are essential in quantum mechanics, providing a lens through which to investigate the correlations of entangled quantum systems and to address challenges like the quantum marginal problem. Though semi-definite programming (SDP) is a recognized method for handling symmetric extensions, it struggles with computational constraints, especially due to the large real parameters in generalized qudit systems. In this study, we introduce an approach that adeptly leverages permutation symmetry. By fine-tuning the SDP problem for detecting k-symmetric extensions, our method markedly diminishes the searching space dimensionality and trims the number of parameters essential for positive-definiteness tests. This leads to an algorithmic enhancement, reducing the complexity from O(d2k) to O(kd2) in the qudit k-symmetric extension scenario. Additionally, our approach streamlines the process of verifying the positive definiteness of the results. These advancements pave the way for deeper insights into quantum correlations, highlighting potential avenues for refined research and innovations in quantum information theory.

Маргиналдылық әлеуметтік-мәдени құбылыс ретінде

Мақала маргиналдылықты әлеуметтік-мәдени құбылыс ретінде қарастыруға арналған. Қазіргі таңдажаңа әлеуметтік күштер мен қатынастардың қалыптасу кезеңінде көптеген қоғамдар, соның ішінде қазақстандық қоғам да белгілі бір дәрежеде құндылықтық-нормативтік вакуумды бастан кешіріп жатқандығына байланысты, дәл осы кезеңде маргинализация процесі күрт күшейіп, өз ауқымында кеңейіп келеді. Жаңа бағдарлардың қалыптасуы жағдайында маргиналды адамдар тұрақты әлеуметтік бағдарлардан айырылады, оларға өздерін жеткілікті сенімділік пен айқындықпен анықтау өте қиын.Маргиналды күй адам бір мәдениеттен кетіп, оны өзінің болмысының сыртқы жазықтығында қалдырып, ол үшін жаңа мәдениетке сәйкес келмейтіндігімен сипатталады, бірақ ол оның сансыз көріністерінің қатысуымен өмір сүреді. Адам жаңа мәдени белгілерді игеру сатысында, бірақ оларды әлі игере алмайды. Бұл өтпелі, шекаралық әлеуметтік-мәдени жағдай ретінде маргиналдылықтың парадоксалды сипаты. Әдетте, маргинализация процесі күрт күшейіп, өз ауқымында кеңейеді. Адамдар сенімсіздік пен әлеуметтік тұрақсыздықты сезінеді. Осыған байланысты бұл мақаланың мақсаты маргиналдылық мәселесін тереңірек зерттеу қажеттілігі болды. Маргиналдылық мәселесін зерттеуге сүйене отырып, жеке адамда біртұтас және алуан түрлі, тұтас, атап айтқанда әмбебап және біртұтас болады деген қорытынды жасауға болады. Осыған байланысты маргинализация мәселесі жеке өзін-өзі анықтау арқылы шешілуі керек. Мақаланы жазуда маргиналдылық мәселелерін зерттеген философтар, әлеуметтанушылар және педагогтердің еңбектері қарастырылды. Авторлар маргиналдылық мәселесін шешуге арналған бірқатар ұсыныстар жасаған.

Estimating the delay margin for stability of linear delay systems by the weighted matrix measure

AbstractIn this paper, the delay margin problem of a linear system with multiple delays is investigated. Estimations for allowable delay bounds of the system are provided in the form of matrix measure. By means of the weighted matrix measure and optimization technologies, the conservatism of estimated delay bounds is reduced. Numerical examples show that the weighted matrix measure has better performance in estimating the delay margin of the system than usual matrix measures.

Coordinated Supply Contracts for a Two-Echelon Supply Chain under Given Bargaining Powers

This paper addresses the supply contracts within a decentralized supply chain comprising an upstream component supplier and a downstream manufacturer. With the need to invest in production capacity before the sales season, suppliers often make conservative capacity decisions due to uncertain demand, which gives rise to the double marginalization problem. The distribution of supply chain profits is typically determined based on each member’s relative bargaining power, often exogenously provided in the market. While numerous studies have been conducted to design supply contracts for coordination in decentralized supply chains, most of them overlook the supplier’s capacity constraints and the existing bargaining power structure. To bridge this gap, this study proposes a supply contract scheme that achieves coordination under any given bargaining power structure. The key finding of this paper is that two contract types, namely capacity cost-sharing (CCS) and surplus capacity compensation (SCC), can address the entire spectrum of bargaining powers. This study demonstrates how to identify a specific threshold for a given bargaining power structure, from which the appropriate contract type is selected. Through numerical illustrations, we present how to select coordinated contracts for different bargaining power structures and examine the influence of contract parameters on the profit of each supply chain member. The primary contribution is that this study provides actionable insights for practitioners to effectively implement coordinated contracts by presenting a straightforward and practical methodology.

A Deletion Algorithm for the Marginal Problem in Propositional Logic Based on Boolean Arrays

This paper proposes a deletion algorithm for the marginal problem in propositional logic. The algorithm is based on the general Davis and Putnam deletion algorithm DP, expressed as a bucket elimination algorithm, representing sets of clauses with the same set of variables employing a Boolean array. The main contribution is the development of alternative procedures when deleting a variable which allow more efficient computations. In particular, it takes advantage of the case in which the variable to delete is determined by a subset of the rest of the variables. It also provides a set of useful results and tools for reasoning with Boolean tables. The algorithms are implemented using Python and the NumPy library. Experiments show that this procedure is feasible for intermediate problems and for difficult problems from hard Bayesian networks cases