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This article reviews the recent developments in digital platform antitrust in China. I first introduce the key players in China's platform industry, particularly those that have been frequently affected by recent antitrust events. I then provide a brief overview of economic theories that are often cited in think tank reports and official documents, including network externalities, hub-and-spoke collusion, and contestable markets. Finally, recent platform antitrust events in China are reviewed, including the introduction of platform antitrust guidelines and major antitrust cases. [ABSTRACT FROM AUTHOR]

This paper econometrically evaluates if collusion actually occurred in the negotiable certificates of deposit (CD) market during the period of Korea Fair Trade Commission's (KFTC) investigation. We propose a general mixture regression model to discriminate the collusion period from the competitive period. We apply our method to Korean CD market data from 1 January 2009 to 23 May 2019 and forecast the probability of collusion for each day. We find that only a small portion—163 days out of 2579 days—of the whole sample is discriminated as a possible collusion. We also find that the banks did not issue the CD on almost all dates discriminated as colluded in our empirical results. Our findings imply a strong possibility that the stickiness of the CD rates was induced by the depressed CD market conditions rather than collusion. [ABSTRACT FROM AUTHOR]

Patent settlements between rivals restrain competition in many different ways. Antitrust requires that their anticompetitive effects are reasonably commensurate with the firms' expectations about (counterfactual) patent litigation. Because these expectations are private and non‐verifiable, this standard is hard to administer; to date, it has been successfully applied only within a very narrow class of agreements. We show that it can be applied universally by policing the economic structure of the firms' contract. This approach determines whether settlement outcomes will be antitrust‐compliant for any private beliefs the firms might have, thus avoiding the need to speculate about such beliefs. [ABSTRACT FROM AUTHOR]

ABSTRACT This study provides an ex-post evaluation of selected filters to find cartels. We evaluate whether filters incurred in type I errors, i.e., failing to recognize the presence of a cartel. We use seven cartel cases in the retail fuel sector in Brazil, for which detailed local price and gross retail margins are available. Cartel cases provided 14 fuel-location events. The evaluated methods include GARCH-based and structural break methods from the international literature and three filters associated with Brazilian antitrust and regulation authorities (ANP, SBDC, and local correlation). All methods are based on an analytical framework which considers cartels as periods of higher average prices (margins) and lower price (margin) variance. Our results indicate that our filters failed to correctly signal most fuel-location cartel events, even using endogenous model-based price changes dates. The problems filters show of detecting actual cartels may be due to difficulties dating cartels or the possibly inappropriate use of price mean-variance markers to evaluate cartel behavior.

Copyright of Contemporary Accounting Research is the property of Canadian Academic Accounting Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Public procurement plays an important role in economy of every country. The vast amounts of money awarded in public contracts, however, make public procurement extremely vulnerable to collusion among competitors and corruption of public officials. Although it is recognized that effective enforcement of these offences requires tight cooperation between competition agencies and other law enforcement authorities, there is still a lot of potential for improvement in many jurisdictions. The objective of this paper is to suggest key features of this cooperation which would facilitate effective catching of both colluding competitors and corrupt public officials involved in bid rigging schemes.

Studying the research results by Nobel prize-winning economists is a fundamentally important task for determining the most promising areas of development of Russian economic science. The author traces the connections between all these works and their predecessors’ work, many of whom were also awarded the Nobel prize in economics. Three lines of development of the predecessors’ achievements are identifid: information asymmetry, limited rationality, the design of market mechanism and new institutionalism. The article does not address the problems of auction theory related to its formal justifiation, which is part of mathematical economics and game theory. However, it is noted that this is an essential part of the laureates’ achievements. The article’s main conclusions are that the prize received for “improving the theory of auctions” fis into the broader economic research context. The winners solved the problems of maintaining free competition and reducing the market’s likelihood of monopolization. The author pays special attention to the results of the empirical analysis of actually implemented auctions. This analysis is divided into three parts, corresponding to the three stages of each auction: starting problems (distrust, the reputation of participants, etc.), the course of the auction (behaviour of participants and results, in particular, the “winner’s curse”.

Today, as market competition intensifies and competition costs rise, manufacturers are increasingly incentivized to engage in anti-competitive contracts or collusion, disrupting the market and harming non-colluding members; on top of all, the growing dominance of e-tailers further complicates supply chain relationships. While addressing the research gap in the specific dynamics between e-tailers and multiple manufacturers in the context of collusion and competition, the principal objective of this article is to get the best sales strategies and decision-making methods according to the standpoint of manufacturers, the e-tailer, and the entire supply chain. This study investigates the relationships and decisions of supply chain members, including an online retailer (e-tailer) and two manufacturers. Our findings indicate that fines for manufacturer collusion and higher e-tailer referral fees can reduce collusion incentives in reselling formats. When both manufacturers sell their products in a reselling sale format, the overall supply chain profit is appreciably higher in all cases, including centralized decision-making, Stackelberg-Bertrand competition, collusion, and deviation. Additionally, different sales formats increase collusion likelihood compared to identical formats, though reselling formats make collusion more sustainable. E-tailers should invest in high-intensity services to boost profitability, while manufacturers prioritize the agency sale format for optimal profits. The findings of this paper are significant as they provide practical guidance for supply chain management and help in monitoring commercial behavior to prevent collusion. [ABSTRACT FROM AUTHOR]

The Journal of Alzheimer's Disease (JAD) has reached its 100th volume, containing over 10,000 articles and nearly 300,000 citations. The journal's focus is on the Alzheimer's disease (AD) community and aims to change the course of AD through new ideas and research. The editor, George Perry, reflects on the journal's beginnings and the importance of community and mentorship. The issue is dedicated to Mark Smith, a collaborator and friend who tragically passed away 14 years ago. [Extracted from the article]

Publicly verifiable random number seeds are widely used in distributed systems and applications, especially in consensus algorithms. The purpose was to distribute the tasks and benefits among the participants fairly. A secure and efficient consensus algorithm is the foundation and guarantee of blockchain. We have been working on more concise, fair, and secure blockchain consensus algorithms. In this paper, we propose a new, more concise, efficient, and publicly verifiable random number seed generation scheme based on the existing secret sharing scheme and one-way function. We combined it with two blockchain consensus algorithms to improve the security and efficiency of the original scheme. • A new collusion resistant publicly verifiable random number method is proposed. • Improving the consensus algorithm with the publicly verifiable random number seeds. • Improving the applicability of the consensus algorithm with random number seeds. [ABSTRACT FROM AUTHOR]

This paper considers the collusive stability of downstream competition in a vertical market with network externalities and cost asymmetry. A dynamic collusion game is constructed, and backward induction is employed to solve the subgame perfect Nash equilibrium. We show that larger network externalities lead to less collusive incentive for an inefficient firm, while for an efficient firm, this depends on the efficiency gap. An increase in network externalities will destabilize the downstream collusion when the cost asymmetry is large and network externalities are relatively weak.

The coin-tossing protocol is an important research area in cryptography. It generates a random bit with uniform distribution even if some participants might fraud. However, traditional coin-tossing protocol could not solve the situation of multiparty. It only divides participants into two parts. In this paper, a new kind of multiparty strict coin-tossing protocol based on the eigenvalue of matrix was proposed. First, matrix tampering attacks can be resisted. On the other hand, collusion attack which was caused by the addition of the Lagrange interpolation formula could be overcome. The analysis shows that the correctness and security of both protocols was guaranteed. Based on the above statements, comparing with the classic coin-tossing protocols, the proposed scheme has the advantage of resisting parties aborting, low complexity, and practicability. [ABSTRACT FROM AUTHOR]

Academic misconduct in all its various forms is a challenge for degree-granting institutions. Whilst text-based plagiarism can be detected using tools such as Turnitin™, Plagscan™ and Urkund™ (amongst others), contract cheating and collusion can be more difficult to detect, and even harder to prove, often falling to no more than a 'balance of probabilities' rather than fact. To further complicate the matter, some students will make deliberate attempts to obfuscate cheating behaviours by submitting work in Portable Document Format, in image form, or by inserting hidden glyphs or using alternative character sets which text matching software does not always accurately detect (Rogerson, Int J Educ Integr 13, 2017; Heather, Assess Eval High Educ 35:647-660, 2010). Educators do not tend to think of academic misconduct in terms of criminality per se, but the tools and techniques used by digital forensics experts in law enforcement can teach us much about how to investigate allegations of academic misconduct. The National Institute of Standards and Technology's Glossary describes digital forensics as 'the application of computer science and investigative procedures involving the examination of digital evidence - following proper search authority, chain of custody, validation with mathematics, use of validated tools, repeatability, reporting, and possibly expert testimony.' (NIST, Digital Forensics, 2021). These techniques are used in criminal investigations as a means to identify the perpetrator of, or accomplices to, a crime and their associated actions. They are sometimes used in cases relating to intellectual property to establish the legitimate ownership of a variety of objects, both written and graphical, as well as in fraud and forgery (Jeong and Lee, Digit Investig 23:3-10, 2017; Fu et. al, Digit Investig 8:44–55, 2011). Whilst there have been some research articles and case studies that demonstrate the use of digital forensics techniques to detect academic misconduct as proof of concept, there is no evidence of their actual deployment in an academic setting. This paper will examine some of the tools and techniques that are used in law enforcement and the digital forensics field with a view to determining whether they could be repurposed for use in an academic setting. These include methods widely used to determine if a file has been tampered with that could be repurposed to identify if an image is plagiarised; file extraction techniques for examining meta data, used in criminal cases to determine authorship of documents, and tools such as FTK™ and Autopsy™ which are used to forensically examine single files as well as entire hard drives. The paper will also present a prototype of a bespoke software tool that attempts to repurpose some of these techniques into an automated process for detecting plagiarism and / or contract cheating in Word documents. Finally, this article will discuss whether these tools have a place in an academic setting and whether their use in determining if a student's work is truly their own is ethical. [ABSTRACT FROM AUTHOR]

Ensuring the integrity of remote data is the prerequisite for implementing cloud-edge computing. Traditional data integrity verification schemes make users spend a lot of time regularly checking their data, which is not suitable for large-scale IoT (Internet of Things) data. On the other hand, the introduction of a third-party auditor (TPA) may bring about greater privacy and security issues. We use blockchain to address the problem of TPA. However, implementing dynamic integrity verification with blockchain is a bigger challenge due to the low throughput and poor scalability of blockchain. More importantly, whether there is a security problem with blockchain-based integrity verification is not yet known. In this paper, we propose a scalable blockchain-based integrity verification scheme that implements fully dynamic operations and blockless verification. The scheme builds scalable homomorphic verification tags based on ZSS (Zhang-Safavi-Susilo) short signatures. We exploit smart contract technology to replace TPA for integrity verification tasks, which not only eliminates the risk of privacy leakage but also resists collusion attacks. Furthermore, we formally define a blockchain-based security model and prove that our scheme is secure under the security assumption of cryptographic primitives. Finally, the mathematical analysis of our scheme shows that both the communication complexity and the communication complexity of an audit are O c , in which c is the number of challenge blocks. We compare our scheme with other schemes, and the results show that our scheme has the lowest time consumption to complete an audit. [ABSTRACT FROM AUTHOR]

Craft guilds were created as a response to certain problems associated with raising royal revenues and securing basic public services in Prague during the medieval and early modern periods. The theory consistent with historical evidence predicts that the rise, spread, and fall of guilds was a result of mutually beneficial bargaining between local craftsmen and their feudal rulers. Guilds enabled craftsmen to utilize the benefits of collusion by offering their capacities to sovereign authorities in exchange for exclusive market privileges. Nevertheless, they created social distortions within their industries in the process. [ABSTRACT FROM AUTHOR]

This paper examines the anti-corruption movement initiated by Kim Jong Un, focusing on the increased rent-seeking competition between the elite and the middle class as market mechanisms have developed in North Korea. I examine two hypotheses regarding this program. First, it is focused on constraining the influence gained by the elite through power-money collusion to maintain regime stability. Second, it aims to support decentralizing economic reforms and the direction of production surplus into state finances, to secure state revenue. In substantiating these hypotheses, I argue that the movement is driven by the goal of capitalizing on the benefits of the market without compromising regime security, by regulating "competitive rent-seeking" between the elite and the middle class. [ABSTRACT FROM AUTHOR]

Benefitting from the outstanding capabilities of intelligent controlling and prediction, federated learning (FL) has been widely applied in Internet of Vehicle (IoV). However, applying FL into fog-computing-based IoV still suffers from two crucial problems: (i) how to achieve the privacy-preserving FL under the flexible architecture of fog computing with no assistance of cloud server, and (ii) how to guarantee the privacy-preserving FL to perform with high efficiency and low overhead in fog-computing settings. For addressing the above issues, we propose a practical framework, named Galaxy, the first of its kind in the regime of privacy-preserving FL under the setting of non-cloud-assisted fog computing. Based on the secure multi-party computation (MPC) technology, our framework satisfies the $\boldsymbol{(T,N)}$ -threshold property, permitting $\boldsymbol{N}$ (a scalable number) fog nodes to cooperate with multiple users for implementing privacy-preserving FL, while resisting the collusion up to $\boldsymbol{T}-\boldsymbol{1}$ fog nodes, and being robust to at most $\boldsymbol{N}-\boldsymbol{T}$ fog nodes simultaneously dropping out. Besides, considering the practical scenario that low-quality data may negatively impair the FL model convergence, our scheme can handle users’ low-quality data while protecting all user-related information under our secure framework. Based on the above superior properties, our scheme can perform with high scalability, high processing efficiency, and low resource overhead, being practical for fog-computing-based IoV. Extensive experiment results demonstrate our scheme with high-level performance. [ABSTRACT FROM AUTHOR]

In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. We may suggest strategies for dealing with them, or invite responses, or both. "Classroom" is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science. Within classrooms, reciprocal rating or a two-way rating system is frequently used in peer reviews of students' performances in group projects or assignments. Intentional distortion of assessment can be achieved in such scenarios through careful contracting between participants. This article shows how a modified score function can be used to stop such kind of collusion between students. [ABSTRACT FROM AUTHOR]

• First-ever large-scale documentation of palm oil conflicts in Indonesia. • In 68% of the studied conflicts communities fail to address their grievances. • Palm oil conflicts generate a 'rightless' form of collective action. • Informalized state institutions foster collusion between powerholders and palm oil companies. • This collusion enables companies to suppress protests of communities against land grabbing. The rapid expansion of oil palm plantations in Indonesia has generated a large and growing number of protests against palm oil companies over, mainly, access to land. So far, these protests have been mainly studied through scattered case studies, which precludes an understanding and analysis of general patterns. Addressing this challenge, this paper presents the results of the first-ever large-scale collaborative effort to document 150 conflicts between rural Indonesians and palm oil companies in four Indonesian provinces (West Kalimantan, Central Kalimantan, Riau and West Sumatra). With this material this article unpacks trajectories of the anti-corporate activism sparked by the rapid expansion of palm oil plantations, discussing the causes, character of protests, conflict resolution efforts and outcomes of these conflicts. We find that palm oil conflicts generate a particular 'rightless' form of collective action: instead of invoking legal provisions or rights, communities often avoid formal institutions while adopting largely accommodative forms of protest aimed at improving their bargaining position vis-à-vis companies. Despite regular and intense protests often directed at local governments, we find that in 68 percent of the studied conflicts communities fail to address their grievances. We argue that this limited success is not just due to the inadequacies of legal frameworks but also to the way in which Indonesia's informalized state institutions foster collusion between powerholders and palm oil companies. Such collusion has facilitated the repression of protests and undermined the effectiveness of conflict resolution mechanisms. [ABSTRACT FROM AUTHOR]

Copyright of Wirtschaft und Wettbewerb is the property of Fachmedien Otto Schmidt KG and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Money laundering is a topical issue, as it concerns both society as a whole, in terms of the public interest, and the individual, in terms of private interest. Money laundering, according to various established definitions, is a criminal way of making a profit from activities specific to the underground economy for which one wants to hide the forms and sources through which they take place. The forms, tools, ways and/or techniques of money laundering know a variety of typologies, which adapt and modernize as they are discovered, analyzed and countered by the bodies and institutions empowered to eradicate them. One tool or means of money laundering, which can be said to be a prerogative of whitecollar workers, is the use of "shell" companies, which are registered and operate legally, have no assets and no activity, only real financial assets. being an intermediary in the money-hiding circuit. These companies are professional organizations, acting in collusion with other commercial or non-commercial entities, banking or non-banking, financial or non-financial, the list being long and varied, intermediaries that also have apparent legality, usually internationally, in countries with jurisdictions. which can hardly be combated. [ABSTRACT FROM AUTHOR]

We document evidence of widespread collusion among construction firms in Japan using a novel data set covering most of the construction projects procured by the Japanese national government. Our data set contains information on about 42,000 auctions whose award amount sums to about $40 billion. We identify collusion by focusing on rebids that occur for auctions in which all (initial) bids fail to meet the secret reserve price. We identify more than 1,000 firms whose conduct is inconsistent with competitive behavior. These bidders were awarded about 15,000 projects, or about 37% of the total number of projects in our sample. [ABSTRACT FROM AUTHOR]

At present, clients can outsource lots of complex and abundant computation, e.g., Internet of things (IoT), tasks to clouds by the "pay as you go" model. Outsourcing computation can save costs for clients and fully utilize the existing cloud infrastructures. However, it is hard for clients to trust the clouds even if blockchain is used as the trusted platform. In this article, we utilize the verification method as SETI@home by only two rational clouds, who hope to maximize their utilities. Utilities are defined as the incomes of clouds when they provide computation results to clients. More specifically, one client outsources two jobs to two clouds and each job contains n tasks, which include k identical sentinels. Two clouds can either honestly compute each task or collude on the identical sentinel tasks by agreeing on random values. If the results of identical sentinels are identical, then client regards the jobs as correctly computed without verification. Obviously, rational clouds have incentives to deviate by collusion and provide identical random results for a higher income. We discuss how to prevent collusion by using deposits, e.g., bit-coins. Furthermore, utilities for each cloud can be automatically assigned by a smart contract. We prove that, given proper parameters, two rational clouds will honestly send correct results to the client without collusion. [ABSTRACT FROM AUTHOR]

Do mergers help or hinder collusion? This article studies the stability of the vitamin cartels in the 1990s and presents a repeated-games approach to quantify "coordinated effects" of a merger. We use data and direct evidence from American courts and European agencies to show the collusive incentive of the short-lived vitamin C cartel was likely to be negative when it actually collapsed in 1995, whereas the incentives of the long-lived cartels (vitamins A and E, and beta carotene) were unambiguously positive until the prosecution in 1999. Simulations suggest some mergers could have prolonged the vitamin C cartel, but others could have further destabilized it, because both the direction and magnitude of coordinated effects depend not only on the number of firms but also on their cost asymmetry. [ABSTRACT FROM AUTHOR]

In the real world, many problems have the need to conduct relevant operations at a specific time. Timed-release encryption (TRE) is a cryptographic primitive in which the sender specifies the decryption time of the receiver, which can meet the above requirement. To address the problem that the current TRE schemes based on the periodic broadcast time trapdoor of the non-interactive time server cannot meet the user's arbitrary specified decryption time, and the interactive time server mode meets the arbitrary decryption time but cannot guarantee the user's identity privacy, a TRE scheme using onion routing network was proposed. In the scheme, when the decryption time approaches, the time trapdoor request was taken as the innermost onion, and the layer by layer encrypted onion was constructed and transmitted to the time server. The time server generates the corresponding time trapdoor and returns it to the receiver according to the original route, so that the user can hide the identity information when making a trapdoor query at any time. Meanwhile, for the node failure problem in the process of onion routing delivery, a method for constructing each layer of onion based on broadcast encryption was proposed, so that each layer of onion node can decrypt that layer of onion. The scheme achieves the trapdoor of successfully querying arbitrary time to the time server while ensuring the anonymity of user's identity. Security analysis showed that the scheme is secure and robust against possible single-point speculation, monitoring attacks, replay attacks, and collusion attacks. Efficiency analysis showed that compared with the pairing-based onion routing scheme, the proposed scheme reduces the time consumption of solving the node failure problem by about 59%, thus realizing efficient anonymous query. [ABSTRACT FROM AUTHOR]

This article investigates the impact of cost difference on vertical collusion between a container port and a liner from the perspective of a shipping container transport chain, taking the deregulation tariff of port authority into consideration. It develops a two-stage game model and then performs simultaneous and sequential games. A finding in this article is that the higher the cost difference between the two shipping container transport chains, the greater the possibility of vertical collusion between the container port and liner. Furthermore, the article found that in the case of an infinite repeated game, the stability of vertical collusion is not only subject to the cost difference but also affected by the terminal handling charge (THC) and collusive choice of counterpart. [ABSTRACT FROM AUTHOR]

Currently, in China, the bidding processes for government socioenvironmental projects face threats of collusion between officials and vendors. This study introduces a coupling and coordination degree-measurement model to study the relationship between the quality of vertical collusion controls and the socioenvironmental system of China based on bidding data taken from 2006 to 2020. The coupling degree describes the socioeconomic influence felt between systems, and the coordination degree refers to their sustainable focused cooperation and mutual influence. The criteria importance through intercriteria correlation method was used to quantify these degrees. To smooth out periods of missing data, the autoregressive integrated moving average model was employed, and the first-order, one-variable, time-series forecasting method was then used to project the trend to 2025. The results revealed that the quality of vertical collusion controls based on the degrees of coupling and coordination between external socioenvironmental and public investment systems ranged from 0.151 to 0.700. Dissonance was detected from 2006 to 2015, but the overall coupling degree has been on an upward trend, peaking in 2020. Currently, the quality of vertical collusion controls is in its primary coordination stage, although it is improving rapidly. From the projected years, both coupling and coordination degrees will enter an intermediate coordination stage by 2022, when the growth rate of the coupling degree is overtaken by that of the coordination degree, as long as active strategies are applied to harmonize the systems in terms of anticollusion measures. [ABSTRACT FROM AUTHOR]

White Americans may find diversity threatening in part because they construe non-White Americans as a coherent social and political force. We argue that this perception manifests in a belief that minority groups collude against White people and that White people should act as a political bloc to defend ingroup interests. In a 3-year longitudinal study, the belief in minority collusion and support for White identity politics increased significantly among a nationally representative sample of 2,635 White Americans. Compared to White Democrats, White Republicans more strongly endorsed minority collusion beliefs and White identity politics, and increased more in these beliefs over time. Essentialist perceptions of the White ingroup were associated with longitudinal increases in minority collusion beliefs, but not in support for White identity politics. Endorsement of minority collusion and support for White identity politics both predicted lower support for Black Lives Matter and greater support for the Alt-Right movement. Implications for race relations, stigma-based solidarity, and the psychology of partisanship and ideology are discussed. [ABSTRACT FROM AUTHOR]

We analyze the ability of firms to sustain collusion in a setting in which horizontally differentiated firms can price discriminate based on private information. Firms receive private, noisy signals regarding customers' preferences. We find that there is a non‐monotonic relationship between signal quality and the sustainability of collusion. Starting from a low level, an increase in signal precision first facilitates collusion. There is, however, a threshold beyond which any further increase renders collusion less sustainable. Our analysis provides important insights for competition policy, particularly in light of firms' growing reliance on increasingly sophisticated computer algorithms to analyze consumer data and to make pricing decisions. In contrast to previous findings, our results reveal that a ban on price discrimination can help to prevent collusive behavior as long as signals are sufficiently noisy. [ABSTRACT FROM AUTHOR]

This paper analyzes price collusion in a repeated game with two submarkets: a standard and a premium quality segment. Within this setting, we study four types of price‐fixing agreement: (i) a segment‐wide cartel in the premium submarket only, (ii) a segment‐wide cartel in the standard submarket only, (iii) two segment‐wide cartels, and (iv) an industry‐wide cartel. We present a complete characterization of the collusive pricing equilibrium and examine the corresponding effect on market shares and welfare. Partial cartels operating in a sufficiently large segment lose market share and the industry‐wide cartel prefers to maintain market shares at precollusive levels. The impact on consumer and social welfare critically depends on the cost of producing quality. Moreover, given that there is a cartel, more collusion can be beneficial for society as a whole. [ABSTRACT FROM AUTHOR]

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to the national economic development form and social development demand, in recent years, the government has been vigorously promoting the control of government-enterprise collusion in the bidding process of government projects in order to promote the standardization of the market. How to predict the vertical collusion behavior under different internal and external environments has become an important research content. Although the prediction of individual behavior is difficult to achieve, the prediction of group behavior has certain possibilities. In this paper, we propose a method for predicting and evaluating the vertical collusion behavior of government investment project bidding based on BP neural network analysis optimized by an annealing algorithm. First, drawing on the traditional evaluation model, the evaluation index system of government-enterprise collusion behavior is constructed from five dimensions: internal environment, external environment, policy development, enforcement effort, and feedback channel. Secondly, a machine learning method based on BP neural network optimized by an annealing algorithm is introduced to evaluate the influence of the change of initial conditions on the bidding collusion behavior. This study has certain significance for government managers to discover the problems and causes in policy formulation, which in turn can support the government in further improving the policy utility. [ABSTRACT FROM AUTHOR]

The classification of collusion behaviors of government-invested project tenderers is one of the important methods to describe the characteristics and laws of collusion behaviors and strengthen the governance of collusion. Firstly, the variables that affect the type of collusion behavior are selected and cluster analysis is carried out on the cases of collusion in government investment project bidding. Then use the social network to mine the types and characteristics of the collusion behavior of the tenderee. Finally, a BP neural network automatic identification model is established to quickly discriminate the types of collusion, which can effectively overcome the subjectivity of traditional methods. As a result, three typical types of collusion of tenderees can be obtained: intervention type, opportunity type, and cooperation type. The study found that the three types of collusion behavior have their own characteristics and laws, and the relationship between the variables that affect the type of collusion behavior is complex and affects each other. [ABSTRACT FROM AUTHOR]

Introduction: Collusion is the non‐disclosure of information about diagnosis or prognosis, frequently encountered in cancer care and palliative services. Unraveling collusion is a skill and differences among communication techniques by Health Care Workers have maintained the process of non‐disclosure to patients and caregivers. Identifying the prevalence of collusion in cancer care is required to improve the existing strategies across the world. Methods: A systematic review of the literature from 1991 to 2020 in the English language was conducted with the protocol registration on PROSPERO ID (CRD 42021249216.) to identify the pooled prevalence of collusion. Results: By using random effect model, the pooled prevalence estimate among patients for the diagnostic and prognostic collusion was 24.15, (95% CI [17.09; 32.96], Tou2 = 1.0801, I2 = 97.9%, Cochran's Q = 1058.22, df = 21, p‐value < 0.001) and 37.92, (95% CI [22.46; 56.30], Tou2 = 1.9641, I2 = 98.6%, Cochran's Q = 944.26, df = 13, p‐value < 0.001) respectively. There was no difference across subgroups with different types of setting for the interview, WHO regions and trend over the years. Conclusions: Substantial prevalence of collusion goes unnoticed in cancer care. A meaningful understanding of such a large prevalence requires inquiry into the existing communication paradigm in cancer care across the world. The findings also question the need of formulating uniform interview techniques and structured assessment tools or questionnaires in cancer care to improve the disclosure rates. [ABSTRACT FROM AUTHOR]

In a recent paper (Ma, Int J Theor Phys 59: 1844–1853, 2020), a multiparty quantum state sharing protocol based on entanglement swapping of Bell states was presented. However, as we show, when the number of agents is more than three, this protocol is insecure in the sense that the first agent and the last one can gain access to the dealer's secret state without the others' cooperation by collusion attack in this protocol. Hence, we propose two improved versions of this protocol in this paper. Security analysis indicates that two improved protocols are secure against the collusion attack and entangled probe attack. The successful ratio analysis shows that two improved protocols can be achieved with probability of 100%. [ABSTRACT FROM AUTHOR]

This article explores the politics of emotions around the recent Hong Kong protests, from the Umbrella Movement in 2014 to the Anti-extradition Movement in 2019–2020. The aim was to articulate the tensions faced by Left-leaning intellectuals in the current political climate in HK, and propose a constructive, ethical and intellectually-acceptable way forward. The recent writings of prominent scholar Ip lam-chong were critically reviewed from an hypothesised position of 'Left in form, Right in essence' (形左實右), using a lens of Left Melancholy. If academics and intellectuals assume this position, the risk is that the dark side of Left Melancholy may remain unacknowledged, and thus pose a barrier to intellectual growth. Left-leaning scholars may focus on retaining connections with the protesters in order to preserve their remaining political capital, at the expense of their intellectual obligations to engage critically with the future. This article discusses the price Left-leaning academics may have to pay to demonstrate loyalty, retain relevance and trustworthiness in the current politics of the HK movement. The risk is that the price could be high: in terms of loss of intellectual integrity, missed opportunities to provide feedback critical to steering the decisions of the movement, and the temptation to sell out to Right-wing populism. [ABSTRACT FROM AUTHOR]

We study the equivalence between non-perfect secret sharing (NSS) and symmetric private information retrieval (SPIR) with arbitrary response and collusion patterns. NSS and SPIR are defined with an access structure, which corresponds to the authorized/forbidden sets for NSS and the response/collusion patterns for SPIR. We prove the equivalence between NSS and SPIR in the following two senses. 1) Given any SPIR protocol with an access structure, an NSS protocol is constructed with the same access structure and the same rate. 2) Given any linear NSS protocol with an access structure, a linear SPIR protocol is constructed with the same access structure and the same rate. We prove the first relation even if the SPIR protocol has imperfect correctness and secrecy. From the first relation, we derive an upper bound of the SPIR capacity for arbitrary response and collusion patterns. For the special case of $\mathsf {n}$ -server SPIR with $\mathsf {r}$ responsive and $\mathsf {t}$ colluding servers, this upper bound proves that the SPIR capacity is $(\mathsf {r}-\mathsf {t})/\mathsf {n}$. From the second relation, we prove that a SPIR protocol exists for any response and collusion patterns. [ABSTRACT FROM AUTHOR]

The popularity of crowdsourcing is on the rise as individuals and organizations seek avenues to solve their problems. The advantages that crowdsourced platforms offer range from outsourcing potentials to reduced costs. There are some challenges with the platforms as workers are likely to collude. Some factors that lead to collusion include communication, nearness to one another and complexity of tasks. This paper presents a survey on crowdsourcing, advantages and disadvantages of crowdsourcing, types of malicious attacks and factors that permit collusion in crowdsourced platforms. [ABSTRACT FROM AUTHOR]

Many collusive agreements involve the exchange of self-reported sales data between competitors, which use them to monitor compliance with a target market share allocation. Such communication may facilitate collusion even if it is unverifiable cheap talk and the underlying information becomes publicly available with a delay. The exchange of sales information may allow firms to implement incentive-compatible market share reallocation mechanisms after unexpected swings, limiting the recourse to price wars. Such communication may allow firms to earn profits that could not be earned in any collusive, symmetric pure-strategy equilibrium without communication. [ABSTRACT FROM AUTHOR]

Although online marketplaces for handmade products persist, little theoretical research has been undertaken to explain why firms choose a handmade strategy. In this paper, I develop a model that can explain the persistence through a handmade effect on the consumer side. I show that when consumers are willing to pay a sufficiently high handmade premium, the firm chooses production by hand over superior machine production. When the firm is part of a duopoly, the existence of consumers who care about the conditions under which a product is manufactured can explain the firms' specialisation and, thus, the observed co-existence of handmade and machine-made products in the economy. Such specialisation is efficient, and can be robust to collusion. The presence of shoppers who are uncertain about the appropriate behaviour may enable the monopolist to use a handmade strategy to signal a social norm of conscious consumption. [ABSTRACT FROM AUTHOR]

To verify that an organization-friendly blockchain system may suffer from forgery and collusion attacks, forgery and collusion attacks were theoretically carried out according to the phase sequence of an organization-friendly blockchain system. Then, the organization-friendly blockchain system was improved and based on the phase sequence forgery and collusion attacks were conducted. The results show that the attacker can obtain illegal transaction data from forgery and collusion attacks on the organization-friendly blockchain system. However, for the improved organization-friendly blockchain, the attacker's forgery and collusion attacks cannot be completed. Therefore, the organization-friendly blockchain system may be subject to forgery and collusion attacks, but the improved organization-friendly blockchain system can prevent such attacks. [ABSTRACT FROM AUTHOR]