Competitive Search Research Articles

Electron-interacting dark matter: Implications from DAMA/LIBRA-phase2 and prospects for liquid xenon detectors and NaI detectors

We investigate the possibility for the direct detection of low mass (GeV scale) WIMP dark matter in scintillation experiments. Such WIMPs are typically too light to leave appreciable nuclear recoils, but may be detected via their scattering off atomic electrons. In particular, the DAMA Collaboration [R. Bernabei et al., Nucl. Phys. At. Energy 19, 307 (2018)] has recently presented strong evidence of an annual modulation in the scintillation rate observed at energies as low as 1 keV. Despite a strong enhancement in the calculated event rate at low energies, we find that an interpretation in terms of electron-interacting WIMPs cannot be consistent with existing constraints. We also demonstrate the importance of correct treatment of the atomic wavefunctions, and show the resulting event rate is very sensitive to the low-energy performance of the detectors, meaning it is crucial that the detector uncertainties be taken into account. Finally, we demonstrate that the potential scintillation event rate can be much larger than may otherwise be expected, meaning that competitive searches can be performed for GeV scale WIMPs using the conventional prompt S1 scintillation signals. This is important given the recent and upcoming very large liquid xenon detectors.

Does Financial Innovation Increase Inequality? A Competitive Search Approach

The distribution of asset holdings among US banks is increasingly concentrated toward a few large banks at the top. Concurrently, the household wealth inequality has increased. This paper provides a theoretical link between these empirical facts, by developing a novel quantitative general equilibrium model that embeds the heterogeneous banking sector into a standard heterogeneous agent model with incomplete-markets. We introduce competitive search to the inter-bank market with adverse selection problem and endogenously generate three different rates of return: savings rate, borrowing rate, and the rate of return on equity. We show that financial innovation — defined as a technological progress that improves the intermediation efficiency — led by the big banks will intensify the adverse selection problem in the inter-bank market and increase the relative size of the big banks over their smaller counterparts. As a result, both the interest rates for borrowing and savings fall, creating even more incentive to borrow for credit constrained households, which ultimately propagates the household wealth inequality.

O transporte público coletivo sob a lógica da produção capitalista do espaço: uma análise do serviço de ônibus na Região Metropolitana do Recife

Resumo Nas sociedades urbanas atuais, o crescimento do papel do Estado convive com o processo de privatização dos serviços prestados por esse aparelho. A justificativa tradicional está na busca por maior competitividade e eficiência nos serviços prestados. Mesmo o Estado sendo cada vez mais indispensável na mediação entre os interesses privados e coletivos, no caso do transporte público coletivo, no contexto brasileiro, a lógica que o constituiu, enquanto serviço de “caráter essencial”, o exime da responsabilidade pública que lhe cabe, abrindo janelas para uma discussão em torno da dinâmica de gestão e de funcionamento desse equipamento. Este artigo analisa o transporte público coletivo, na Região Metropolitana do Recife, sob a lógica da produção capitalista do espaço.

Gestión de la marca Ciudad de México (CDMX) y su impacto económico

Ante la globalización, los gobiernos y las empresas turísticas buscan generar ventajas competitivas que las distingan del resto del mercado. En este documento se explora la manera en que la gestión de la marca de la Ciudad de México (CDMX) apoya esta búsqueda de competitividad, considerando el entorno, su composición y relaciones.Se emplea una metodología de análisis documental, exploratorio y transversal que permite comparar la gestión de la marca CDMX, con su posicionamiento y la derrama económica en cuanto a la hotelería, dada la necesidad de análisis de los resultados económicos para considerar la viabilidad del producto.

A memetic algorithm with competition for the capacitated green vehicle routing problem

In this paper, a memetic algorithm with competition &#x0028 MAC &#x0029 is proposed to solve the capacitated green vehicle routing problem &#x0028 CGVRP &#x0029. Firstly, the permutation array called traveling salesman problem &#x0028 TSP &#x0029 route is used to encode the solution, and an effective decoding method to construct the CGVRP route is presented accordingly. Secondly, the k-nearest neighbor &#x0028 kNN &#x0029 based initialization is presented to take use of the location information of the customers. Thirdly, according to the characteristics of the CGVRP, the search operators in the variable neighborhood search &#x0028 VNS &#x0029 framework and the simulated annealing &#x0028 SA &#x0029 strategy are executed on the TSP route for all solutions. Moreover, the customer adjustment operator and the alternative fuel station &#x0028 AFS &#x0029 adjustment operator on the CGVRP route are executed for the elite solutions after competition. In addition, the crossover operator is employed to share information among different solutions. The effect of parameter setting is investigated using the Taguchi method of design-of-experiment to suggest suitable values. Via numerical tests, it demonstrates the effectiveness of both the competitive search and the decoding method. Moreover, extensive comparative results show that the proposed algorithm is more effective and efficient than the existing methods in solving the CGVRP.

Knowledge management practices in technology parks: case study - Technology Park TECNOPUC

Abstract The constant search for competitiveness has become a mandatory practice to ensure the survival and growth of the organization, in this context of fierce competition enterprises, cities, regions and entire countries are seeking ways to ensure its sustainability, anchored in knowledge and constant innovation. The Technology Parks have proved development tools aligned to these new challenges, assisting in technological strengthening and integration of cities, regions and nations in the knowledge economy. These innovation centers, production, dissemination and use of knowledge are intensive, and management becomes imperative. Thus, Knowledge Management meets this need, and although it has achieved a consolidated stage as a research field, its relationship with the Technological Parks was little explored in the literature. Based on the analysis and reflection of these research gaps, this paper aims to propose a set of guidelines for the development of Knowledge Management in Technology Parks. To this end, was developed, validated and applied a data collection instrument in five Technological Park, four in Brazil and one in Spain. The selected case studies were analyzed, identifying initiatives, programs and tools related to knowledge management. Finally, based on these results, was proposed the mentioned guidelines.

Fixed vs. Flexible Pricing in a Competitive Market

We study the selection and dynamics of two popular pricing policies—fixed price and flexible price—in competitive markets. Our paper extends previous work in marketing, for example, Desai and Purohit (2004) by focusing on decentralized markets with a dynamic and fully competitive framework while also considering possible noneconomic aspects of bargaining. We construct and analyze a competitive search model, which allows us to endogenize the expected demand depending on pricing rules and posted prices. Our analysis reveals that fixed and flexible pricing policies generally coexist in the same marketplace, and each policy comes with its own list price and customer demographics. More specifically, if customers dislike haggling, then fixed pricing emerges as the unique equilibrium, but if customers get some additional satisfaction from the bargaining process, then both policies are offered, and the unique equilibrium exhibits full segmentation: haggler customers avoid fixed-price firms and exclusively shop at flexible firms, whereas nonhaggler customers do the opposite. We also find that prices increase in customer satisfaction, implying that sellers take advantage of the positive utility enjoyed by hagglers in the form of higher prices. Finally, considering the presence of seasonal cycles in most markets, we analyze a scenario in which market demand goes through periodic ups and downs and find that equilibrium prices remain mostly stable despite significant fluctuations in demand. This finding suggests a plausible competition-based explanation for the stability of prices. The online appendix is available at https://doi.org/10.1287/mnsc.2017.2922 . This paper was accepted by J. Miguel Villas-Boas, marketing.

INTERNATIONAL TRADE AND LABOR-MARKET DISCRIMINATION

textabstractWe embed a competitive search model with labor market discrimination, or nepotism, into a two-sector, two-country framework in order to analyze how labor market discrimination impacts the pattern of international trade and also how trade trade affects discrimination. Discrimination, or nepotism, reduces the matching probability and output in the skilled-labor intensive differentiated-product sector so that the country with more discriminatory firms has a comparative advantage in the simple sector. As countries alter their production mix in accordance with their comparative advantage, trade liberalization can then reinforce the negative effect of discrimination on development in the more discriminatory country and reduce its effect in the country with fewer discriminatory firms. Similarly, the profit difference between non-discriminatory and discriminatory firms increases in the less discriminatory country and shrinks in the more discriminatory one. In this way trade can further reduce discrimination in a country where it is less prevalent and increase it where it is more firmly entrenched.

A Networked Desktop Virtual Reality Setup for Decision Science and Navigation Experiments with Multiple Participants

Investigating the interactions among multiple participants is a challenge for researchers from various disciplines, including the decision sciences and spatial cognition. With a local area network and dedicated software platform, experimenters can efficiently monitor the behavior of the participants that are simultaneously immersed in a desktop virtual environment and digitalize the collected data. These capabilities allow for experimental designs in spatial cognition and navigation research that would be difficult (if not impossible) to conduct in the real world. Possible experimental variations include stress during an evacuation, cooperative and competitive search tasks, and other contextual factors that may influence emergent crowd behavior. However, such a laboratory requires maintenance and strict protocols for data collection in a controlled setting. While the external validity of laboratory studies with human participants is sometimes questioned, a number of recent papers suggest that the correspondence between real and virtual environments may be sufficient for studying social behavior in terms of trajectories, hesitations, and spatial decisions. In this article, we describe a method for conducting experiments on decision-making and navigation with up to 36 participants in a networked desktop virtual reality setup (i.e., the Decision Science Laboratory or DeSciL). This experiment protocol can be adapted and applied by other researchers in order to set up a networked desktop virtual reality laboratory.

WORKER TURNOVER AND UNEMPLOYMENT INSURANCE

AbstractThis article studies a competitive search model of the labor market with learning about match‐specific productivity in which risk‐averse workers factor present and future unemployment risks in their search decisions. We examine internally efficient equilibrium allocations in which match termination occurs only if the joint value of a worker–firm pair is negative. Internal efficiency poses a trade‐off between present and future risks. Public insurance provision also affects this trade‐off and, hence, worker turnover and job composition. In addition to unemployment benefits, the implementation of the planner's allocation requires a negative income tax and a 0 layoff tax.

Bidding for incentive contracts

Principals seek to enter into a productive relationship with agents by posting mechanisms in a market with competitive search. A mechanism includes an incentive contract if the meeting is bilateral, and an ex post bidding process, in which agents make contract offers, if several agents meet the same principal. In equilibrium, the bidding process induces a lottery over two contracts. The main result is that the equilibrium allocation is not constrained welfare optimal, precisely because of this contracting risk. This stands in contrast to known results. Hence the optimality of such ex post bidding mechanism is sensitive to the extensive form, as well as to risk aversion. Correcting the allocation is possible, but may be heavy-handed.

A Case Study of On-the-fly Wide-field Radio Imaging Applied to the Gravitational Wave Event GW151226

Abstract We apply a newly developed on-the-fly mosaicing technique on the Jansky Very Large Array (VLA) at 3 GHz in order to carry out a sensitive search for an afterglow from the Advanced LIGO binary black hole merger event GW151226. In three epochs between 1.5 and 6 months post-merger, we observed a 100 deg2 region, with more than 80% of the survey region having an rms sensitivity of better than 150 μJy/beam, in the northern hemisphere with a merger containment probability of 10%. The data were processed in near real time and analyzed to search for transients and variables. No transients were found but we have demonstrated the ability to conduct blind searches in a time-frequency phase space where the predicted afterglow signals are strongest. If the gravitational wave event is contained within our survey region, the upper limit on any late-time radio afterglow from the merger event at an assumed mean distance of 440 Mpc is about 1029 erg s−1 Hz−1. Approximately 1.5% of the radio sources in the field showed variability at a level of 30%, and can be attributed to normal activity from active galactic nuclei. The low rate of false positives in the radio sky suggests that wide-field imaging searches at a few Gigahertz can be an efficient and competitive search strategy. We discuss our search method in the context of the recent afterglow detection from GW170817 and radio follow-up in future gravitational wave observing runs.

Corporate Sustainability – From a Fuzzy Concept to a Coherent Reality

Abstract During the last few decades, the search for sustainability has experienced a tremendous momentum, encompassing all the levels of the global system. Fuelled by complex (both proactive and reactive) motivators, the process has surpassed the characteristics of an intellectual endeavor – more preoccupied by idealist goals, and less focused on the actual means to achieve them – and has proved that it can successfully be transposed into the corporate real world – of decision making, objective assessment, and relentless scrutiny. The paper aims to (broadly) explore the world of the most sustainable corporations – based on a descriptive (factual and dynamic) analysis of Corporate Knight’s annual rankings (2016-2018) of the Most Sustainable Corporations – in order to: (a). determine (by comparing and contrasting) the main features these organizations – able to transform the fuzzy concept of corporate sustainability into a coherent reality – display; and (b). set the premises for future (narrower) researches – aiming to explain the “how-s” behind the design, development and implementation of the strategies these corporations follow in their search for (sustainable) competitiveness.

The Price of Capital, Factor Substitutability, and Corporate Profits

The capital-to-labor ratio has steadily risen in the U.S. and elsewhere during the post-WWII period. Since the 1970s this rise has been accompanied by a rise in the level and variability of corporate profits whereas the labor share of income has declined. In this paper we ask whether these trends are related in that they can be explained by a common determinant such as the observed decline in the relative price of new capital goods, or the change in production technology towards increased substitutability between capital and labor. We use a dynamic stochastic equilibrium model of competitive search in the labor market augmented by a CES production function that allows firms to substitute between capital and labor at varying degrees. By assumption, firms can adjust capital more easily than labor. Profits arise from rents paid to quasi-fixed factors of production. We find that the declining relative price of capital and the increase in factor substitutability each causes the capital-to-labor ratio and corporate profits to rise, but only increased factor substitutability generates the observed decrease in the labor share of income and increases the relative variability of profits.

Exploratory Analysis of Modularization Strategy Based on the Theory of Constraints Thinking Process

The search for competitiveness has led companies to increase the variety of products on offer in their portfolios with the aim of broadening their consumer market. However, there is a trade-off between increasing product variety and operational performance. Thus, the aim of this paper is to analyze the critical root causes that can prevent manufacturing companies from obtaining sustainable growth, by showing how modularization strategy can contribute in this area. In order to achieve the proposed objective, a bibliographical review was carried out for the topic, and an effect–cause–effect analysis was subsequently structured using the theory of constraints thinking process. From the main results, it was possible to identify that, besides the use of modularization strategy, supplier participation in the product development process needs to be considered, as well as defining constraints in the flow of production and postponing the definition of final products. Another contribution from the article is it presents an integrated effect–cause–effect analysis that lays out the contributions from modularization strategy. Adopting the strategy can contribute toward manufacturing companies obtaining sustainable growth.

A Model of Capital Structure Under Labor Market Search

This paper develops a competitive search equilibrium model of capital structure and labor outcomes. In the model, employers design capital structures and compete for workers subject to idiosyncratic productivity shocks and labor search frictions. The capital structure policy reflects the trade-off between the strategic benefit of debt in wage bargaining and the cost of debt in labor hiring. The model generates rich comparative static implications regarding the impacts of productivity, credit and labor market factors on leverage and labor outcomes. A calibration yields a large wage dispersion and a highly elastic labor market tightness with respect to productivity.

A general framework for searching on a line

Consider the following classical search problem: a target is located on a line at distance D from the origin. Starting at the origin, a searcher must find the target with minimum competitive cost. The classical competitive cost studied in the literature is the ratio between the distance travelled by the searcher and D. Note that when no lower bound on D is given, no competitive search strategy exists for this problem. Therefore, all competitive search strategies require some form of lower bound on D.We develop a general framework that optimally solves several variants of this search problem. Our framework allows us to achieve optimal competitive search costs for previously studied variants such as: (1) where the target is fixed and the searcher's cost at each step is a constant times the length of the step, (2) where the target is fixed and the searcher's cost at each step is the length of the step plus a fixed constant (often referred to as the turn cost), (3) where the target is moving and the searcher's cost at each step is the length of the step.Our main contribution is that the framework allows us to derive optimal competitive search strategies for variants of this problem that do not have a solution in the literature such as: (1) where the target is fixed and the searcher's cost at each step is α1x+β1 for moving distance x away from the origin and α2x+β2 for moving back with constants α1,α2,β1,β2, (2) where the target is moving and the searcher's cost at each step is a constant times the length of the step plus a fixed constant turn cost. Notice that the latter variant can have several interpretations depending on what the turn cost represents. For example, if the turn cost represents the amount of time for the searcher to turn, then this has an impact on the position of the moving target. On the other hand, the turn cost can represent the amount of fuel needed to make an instantaneous turn, thereby not affecting the target's position. Our framework addresses all of these variations.

Competitive search equilibrium with multidimensional heterogeneity and two-sided ex-ante investments

We analyze a competitive (price-taking) search model where workers and firms make costly investments (e.g. in education and physical capital, respectively) before they enter the labor market. The environment features transferable utility and symmetric information. A key novelty with respect to existing work is that we allow for multidimensional heterogeneity on both sides of the market. The probabilities of finding and filling different jobs and the corresponding wages are determined endogenously in equilibrium. We show that constrained efficient allocations can be determined as optimal solutions to a linear programming problem, whereas the prices supporting these allocations and the associated expected payoffs for workers and firms correspond to the solutions of the ‘dual’ of that linear program. We use this characterization to show that an equilibrium exists and is constrained efficient under very general conditions. The fact that linear programming techniques are used for the structural estimation of frictionless matching models suggests that our framework is potentially useful for empirical studies of labor markets and other markets where search frictions are prevalent.

Competitive Search with Ex-post Opportunism

Abstract:We consider a frictional market where an element of the terms of trade (price or quantity) is posted ex-ante (before the matching process) while the other is determined ex-post. By doing so, sellers can exploit their local monopoly power by adjusting prices or quantities once the local demand is realized. We find that when sellers can adjust quantities ex-post, there exists a unique symmetric equilibrium where an increase in the buyer-seller ratio leads to higher quantities and prices. When buyers instead can choose quantities ex-post, a higher buyer-seller ratio leads to higher prices but lower traded quantities. These equilibrium allocations are generically constrained inefficient in both intensive and extensive margins. When sellers post ex-ante quantities and adjust prices ex-post, a symmetric equilibrium exists where buyers obtain no surplus from trade. This equilibrium allocation is not constrained efficient either. If buyers choose prices ex-post, there is no trade in equilibrium when entry is costly.

Peer-to-Peer Markets with Bilateral Ratings

We consider a platform that matches service providers with potential customers. Ratings of a service provider reveal the quality of his service while ratings of a consumer reveal the cost to serve her. Under a competitive search framework, we study how bilateral ratings influence market competition and segmentation. Two types of equilibria exist under bilateral ratings. In the first type, low-cost consumers only apply to high-quality service providers, who post a higher price, have longer queues and are less likely to accept an application than low-quality providers. High-cost consumers apply to all service providers and have a lower acceptance rate. In the second type of equilibria, both high- and low-quality service providers serve all consumers. Across all equilibria, equilibrium prices may decrease as the fraction of high-quality providers increases, as consumers become more costly to serve, and as the platform's commission rate increases. Compared with a platform with unilateral ratings where only service providers are rated, a platform with bilateral ratings may soften service providers' competition, leading to higher equilibrium prices. Lastly, we find that in the case of incomplete market coverage, high-quality service providers may charge lower prices than low-quality providers in equilibrium, because by charging a lower price, a high-quality service provider attracts more consumer applications, which enables him to cherrypick a low-cost consumer, while a low-quality service provider faces with consumers with higher serving costs and thus charge a higher price to make up the serving cost.