Exploitative Behavior Research Articles

Switching spatial scale reveals dominance-dependent social foraging tactics in a wild primate.

When foraging in a social group, individuals are faced with the choice of sampling their environment directly or exploiting the discoveries of others. The evolutionary dynamics of this trade-off have been explored mathematically through the producer-scrounger game, which has highlighted socially exploitative behaviours as a major potential cost of group living. However, our understanding of the tight interplay that can exist between social dominance and scrounging behaviour is limited. To date, only two theoretical studies have explored this relationship systematically, demonstrating that because scrounging requires joining a competitor at a resource, it should become exclusive to high-ranking individuals when resources are monopolisable. In this study, we explore the predictions of this model through observations of the natural social foraging behaviour of a wild population of chacma baboons (Papio ursinus). We collected data through over 800 h of focal follows of 101 adults and juveniles across two troops over two 3-month periods. By recording over 7,900 social foraging decisions at two spatial scales we show that, when resources are large and economically indefensible, the joining behaviour required for scrounging can occur across all social ranks. When, in contrast, dominant individuals can aggressively appropriate a resource, such joining behaviour becomes increasingly difficult to employ with decreasing social rank because adult individuals can only join others lower ranking than themselves. Our study supports theoretical predictions and highlights potentially important individual constraints on the ability of individuals of low social rank to use social information, driven by competition with dominant conspecifics over monopolisable resources.

Unbundling the effect of prior invention experience from firm size on future exploratory and exploitative search

This paper examines the role of prior invention experience on future search activities within the pharmaceutical industry. Specifically, we examine to what extent prior invention experience influences future exploratory and exploitative search behavior by firms. The results indicate there is a negative relationship between prior experience and future exploratory search, but a positive effect of prior experience on future exploitative search. Additionally, we find that these effects are moderated by firm size. Specifically, firm size mitigates the negative relationship between prior experience and future exploratory search, and also weakens the positive relationship between prior experience and future exploitative search.

How Performance Incentives Shape Individual Exploration and Exploitation: Evidence from Microdata

The existing literature has highlighted the role of individuals in exploration and exploitation, yet our understanding of what shapes those activities at the individual level remains limited. We integrate the literatures on exploration/exploitation and incentives to examine how incentives impact individual behavior to explore new ideas or exploit existing ideas. Using novel microdata on the commercial projects of sales employees at a South Korean e-commerce firm, we find that individuals engage in relatively more exploration when performance-based incentives are weakened; yet, interestingly, this increase in exploration is driven mainly by high-performing individuals in our setting. Weakening performance-based incentives also lead to higher exploration performance via experiential learning, especially for individuals who work in complex task environments. Overall, this study contributes to the literature on exploration/exploitation by examining how individual exploration and exploitation behavior and performance is shaped by incentives. We also contribute to the incentives literature by investigating the implications of incentives in an important domain, namely, that of knowledge exploration behavior. This study also provides insights into important individual-level microfoundations of firm capabilities and performance by highlighting the important role of individuals in exploration/exploitation activities and how this role is contextualized by the incentives a firm deploys.

Quorum-quenching limits quorum-sensing exploitation by signal-negative invaders

Some bacteria produce and perceive quorum-sensing (QS) signals that coordinate several behaviours, including the costly processes that are exoenzyme production and plasmid transfer. In the case of plasmid transfer, the emergence of QS signal-altered invaders and their policing are poorly documented. In Agrobacterium tumefaciens, the virulence Ti-plasmid encodes both synthesis and sensing of QS-signals, which promote its transfer from a donor to a recipient cell. Here, we reported that QS-altered A. tumefaciens mutants arose during experimental evolution. All showed improved growth compared to their ancestor. Genome sequencing revealed that, though some had lost the Ti-plasmid, most were defective for QS-signal synthesis and Ti-plasmid conjugation (traR mutations) and one exhibited a QS-signal exploitation behaviour, using signal produced by other cells to enhance its own Ti-plasmid transfer. We explored mechanisms that can limit this QS-hijacking. We showed that the A. tumefaciens capacity to inactivate QS-signals by expressing QS-degrading enzyme could attenuate dissemination of the QS signal-negative Ti-plasmids. This work shows that enzymatic QS-disruption whether encoded by the QS-producing Ti-plasmid itself, by a companion plasmid in the same donor cells, or by one in the recipient cells, in all cases can serve as a mechanism for controlling QS exploitation by QS signal-negative mutants.

Bond repurchase objectives and the repurchase method choice

This study investigates how firm׳s bond repurchase objective affects its choice of repurchase method. Unlike tender offers, open-market repurchases are not pre-announced and buyer׳s identity is unknown to the seller. We provide evidence that firms are likely to repurchase on the open-market when bonds are mispriced and when firms seek to manage their financial reports, either to meet earnings targets or avert debt covenant violations. When firms seek to amend indenture terms, they prefer tender offers. We also find that firm׳s information quality affects the likelihood of mispricing exploitation behavior and that insiders buy firm׳s stocks around open-market repurchases.

Individual ambidexterity: the duality of exploration and exploitation and its relationship with innovative performance

ABSTRACTOrganizational ambidexterity has been established as an important antecedent of organizational innovation and performance. Recently, researchers have started to argue that ambidexterity is not only essential at the organizational, but also at the individual level. Thus, to be innovative, individuals need to engage in both explorative and exploitative behaviours. However, questions remain regarding the optimal balance of explorative and exploitative behaviours and how ambidexterity can be operationalized. At the organizational level, most empirical research utilized either the difference between, or the product of, exploration and exploitation. In this article, we criticize these approaches on conceptual and methodological grounds and argue for an alternative operationalization of ambidexterity: polynomial regression and response surface methodology. In two diary studies with daily and weekly data, we demonstrate the advantages of this approach. We discuss implications for ambidexterity research and innovation practice.

Parametric modulation of reward sequences during a reversal task in ACC and VMPFC but not amygdala and striatum

Several regions of the frontal cortex interact with striatal and amygdala regions to mediate the evaluation of reward-related information and subsequent adjustment of response choices. Recent theories discuss the particular relevance of dorsal anterior cingulate cortex (dACC) for switching behavior; consecutively, ventromedial prefrontal cortex (VMPFC) is involved in mediating exploitative behaviors by tracking reward values unfolding after the behavioral switch. Amygdala, on the other hand, has been implied in coding the valence of stimulus-outcome associations and the ventral striatum (VS) has consistently been shown to code a reward prediction error (RPE). Here, we used fMRI data acquired in humans during a reversal task to parametrically model different sequences of positive feedback in order to unravel differential contributions of these brain regions to the tracking and exploitation of rewards. Parameters from an Optimal Bayesian Learner accurately predicted the divergent involvement of dACC and VMPFC during feedback processing: dACC signaled the first, but not later, presentations of positive feedback, while VMPFC coded trial-by-trial accumulations in reward value. Our results confirm that dACC carries a prominent confirmatory signal during processing of first positive feedback. Amygdala coded positive feedbacks more uniformly, while striatal regions were associated with RPE.

Enol and Ynol Surrogates: Promising Substrates for Hypervalent Iodine Chemistry

AbstractIn numerous iodine(III)‐mediated methodologies that involve ketone compounds, the enol tautomer is expected to be the reactive species. In this context, the exploration of enol and ynol surrogates as substrates is of great interest. Activated π‐systems have been shown to exhibit interesting and highly exploitable behavior toward hypervalent iodine reagents. This has led to the development of numerous useful oxidative transformations. Enamines, enamides, enol derivatives, haloalkenes, and haloalkynes are all enol or ynol surrogates that are reactive towards the most popular iodanes and iodonium salts. This Focus Review will describe past and on‐going research involving these substrates to gain insight into the similarities and disparities observed in their reactivity profiles.

Intelligent Multiple Search Strategy Cuckoo Algorithm for Numerical and Engineering Optimization Problems

This paper presents intelligent multiple search strategy algorithm (IMSS) as a new modification of cuckoo search (CS) to improve performance of the conventional algorithm. To do so, the proposed IMSS algorithm adopts a multiple search strategy and Q-learning technique. The introduced multiple search strategy couples CS and covariance matrix adaptation evolution strategy (CMAES) to explore search space more efficiently and also to reduce computational time of finding the optimal solution. More precisely, CS enables the IMSS to achieve better accuracy of final solutions through Levy flights, and CMAES enhances its convergence rate via a concept known as evolution path. To provide an intelligent balance between the exploration and exploitation behaviors, the IMSS employs Q-learning method and thereby acquires information about the performance of each search strategy. Then, it uses this information to dynamically select the best strategy for evolving candidate solutions as optimization process progress. In other words, the IMSS algorithm transforms the task of learning the optimal policy in Q-learning into the search for an efficient and adaptive optimization behavior. The IMSS is evaluated on CEC 2005 and CEC 2013 test suites, and its results are compared with results produced by several state-of-the-art algorithms. For further validation, the presented approach is also applied on two well-studied engineering design problems. The obtained results indicate that the IMSS provides very competitive results compared to other algorithms on the aforementioned optimization problems.

Life History Theory and Exploitative Strategies

Exploitative strategies involve depriving others of resources while enhancing one’s own. Life history theory suggests that there are individual differences (life history strategy) and environmental characteristics (life history contingencies [LHCs]) that influence the use of exploitative strategies. However, past work manipulating LHCs has found mixed evidence for the influence of this information on exploitative behavior. We present three studies that help clarify the effects of this type of information. Results indicated that younger individuals are most sensitive to LHC information. We also found, contrary to predictions, that communicating slow LHC information (i.e., high population density, intraspecific competition, and resource scarcity) increased rather than decreased the temptation to engage in exploitative behavior. Limitations and future directions are discussed.

Looking for the right time to shift strategy in the exploration/exploitation dilemma

Balancing exploratory and exploitative behavior is an essential dilemma faced by adaptive agents. The challenge of finding a good trade-off between exploration (learn new things) and exploitation (act optimally based on what is already known) has been largely studied for decision-making problems where the agent must learn a policy of actions. In this paper we propose the engaged climber method, designed for solving the exploration-exploitation dilemma. The solution consists in explicitly creating two different policies (for exploring or for exploiting), and to determine the good moments to shift from the one to the other by the use of notions like engagement and curiosity.

Model test study on the subsidence of high-rise building group due to variation of groundwater level

With the rapid urbanization, more and more attention has been paid to land subsidence, especially induced by the coupling effect of high-rise building groups and variation of groundwater level in soft soil areas. A model test of the subsidence of a high-rise building group undergoing the groundwater withdrawal and the recharge from different aquifers was conducted and discussed in this paper. The particle image velocimetry technology was used to analyze the long-term deformation of each soil layer, and the results were in good agreement with those measured by LVDTs. The exploitation of groundwater from the deeper aquifer was a good way to control the settlement to some extent, but the subsidence cannot be avoided completely. During the dewatering, the settlement of the soil layer was out of phase with that of the pile foundation, so the negative friction appeared along the pile and the soil settlement was hindered. The compression of two aquitards was the main reason for land subsidence, which was attributed to the decrease in pore water pressure at first following expansion of unsaturated area and the occurrence of high matric suction afterward, as well as the high compressibility of silty clay. The land subsidence caused by the variation of groundwater level was irreversible, and the behavior of water recharge and exploitation in the multilayer soils was not elastic. However, the groundwater recharge had a significant effect on restraining the settlement rate.

A discrete artificial bee colony algorithm for single machine scheduling problems

This paper presents a discrete artificial bee colony algorithm for a single machine earliness–tardiness scheduling problem. The objective of single machine earliness–tardiness scheduling problems is to find a job sequence that minimises the total sum of earliness–tardiness penalties. Artificial bee colony (ABC) algorithm is a swarm-based meta-heuristic, which mimics the foraging behaviour of honey bee swarms. In this study, several modifications to the original ABC algorithm are proposed for adapting the algorithm to efficiently solve combinatorial optimisation problems like single machine scheduling. In proposed study, instead of using a single search operator to generate neighbour solutions, random selection from an operator pool is employed. Moreover, novel crossover operators are presented and employed with several parent sets with different characteristics to enhance both exploration and exploitation behaviour of the proposed algorithm. The performance of the presented meta-heuristic is evaluated on several benchmark problems in detail and compared with the state-of-the-art algorithms. Computational results indicate that the algorithm can produce better solutions in terms of solution quality, robustness and computational time when compared to other algorithms.

Identity and Power Use in Exchange Networks

We introduce a theoretical argument about how the fairness identity influences exchange behaviors in negotiated exchange networks. To test this argument, we use data from a laboratory experiment. Results demonstrate that by providing manipulated feedback that is inconsistent with the fairness identity standard ( actual appraisals), inequality changes in the direction that counteracts the feedback. In addition, when high power actors think their high power exchange partners view them as either more or less fair than how they see themselves ( reflected appraisals), inequality again changes in the direction that counteracts the nonverifying feedback. We discuss how considering both identity and exchange processes yields new insights into exploitative behavior in exchange.

The Palaeovegetation of Janruwa (Nigeria) and its Implications for the Decline of the Nok Culture

Settlement activities of the Nok Culture considerably decreased around 400 BCE and ended around the beginning of the Common Era. For a better understanding of the decline of the Nok Culture, we studied the charcoal assemblage of the post-Nok site Janruwa C, dating to the first centuries CE. Janruwa C differs from Middle Nok sites in ceramic inventory and a wider set of crops. 20 charcoal types were identified. Most taxa are characteristic of humid habitats such as riverine forests, while those savanna woodland charcoal types that had been dominant in Middle Nok samples are only weakly represented. The differences between the Middle Nok and post-Nok assemblages do not indicate vegetation change, but rather different human exploitation behaviors. It seems that the Nok people avoided forest environments while in the first centuries CE, other, possibly new populations settled closer to the forest and were more familiar with its resources. The new exploiting strategies might be explained as adaptation to changing environmental conditions. Our results, together with data from other palaeo-archives in the wider region, point to climatic change as a potential factor for the decline of the Nok Culture. We argue that erosion on the hill slopes, maybe due to stronger seasonality, was responsible for land degradation after 400 BCE and that the Nok people were not flexible enough to cope with this challenge through innovations.

Stable Isotopic Detection of Manual Intervention Among the Faunal Assemblage from a Majiayao Site in NW China

AbstractFaunal remains from Shannashuzha in Minxian County, Gansu Province, China were isotopically analyzed to understand animal husbandry, and thus human subsistence strategy, during the Majiayao culture (5200–4800 cal yr BP) period. Stable carbon isotopic results reveal that only two pig samples clearly show a C4-dominated diet with a mean δ13C value of –8.5‰, which possibly indicated controlled feeding practices by human beings. No other significant manual intervention can be observed among the remaining samples, suggesting that both wild and domesticated meat sources were used at Shannashuzha. Statistically, Bos are indistinguishable from Cervidae based solely on isotopic results, suggesting that Bos may have remained in wild form during the Majiayao culture period. The presence of hare/rabbit, bamboo rat, and badger reflects the diversified food exploitation behavior.

The Use of Accommodation in Buyer–Seller Relationships: Encouraging or Controlling Opportunism in Business Markets Middle-grounds

ABSTRACTPurpose: In the past decades, marketing researchers have explored different strategies to control opportunism in buyer–seller relationships. Accommodation, the cooperative response to partners’ exploitive behavior in exchange relationships, has received increasing attention from research on interfirm relationships. However, less is known about whether accommodation is an effective response strategy for controlling opportunism. Drawing on the self-enforcing agreement literature, this article focuses on exploring (1) what drives a firm’s accommodation response to its partner’s exploitive behavior, (2) how a firm’s accommodation helps govern its exchange partner’s opportunistic behavior, and (3) whether monitoring magnifies or buffers the effect of accommodation on the exchange partners’ opportunism.Methodology: The survey data were collected from 173 seller-firms in Guangdong, Shanghai, Beijing, Wuhan, and Zhengzhou, representing the south, east, north, and middle regions of China. The initial questionnaires were distributed mainly by mail. By assessing the nonresponse bias and the potential bias of early and late responses, we detected no significant differences, implying that the aforementioned biases are not a concern. Because PLS can readily model both formative and reflective constructs, and accommodation is a formative construct, we deployed the SmartPLS software program to test our model.Findings: This article enables a deeper understanding of accommodation as a response strategy in buyer–seller relationships. The data analysis offers supportive evidence that a firm’s level of accommodation is positively related to two exchange attributes: joint-specific investments and observability of the exchanges. Accommodation, as a cooperative response strategy, curtails opportunism in buyer–seller relationships, and such a curtailing role is magnified when accompanied with monitoring.Originality/value/contribution: The authors develop a framework to examine previously untested relationships, which suggest accommodation is a cooperative response strategy to mitigate opportunism. We also contribute by exploring the antecedents of accommodation from the tangible transaction attributes perspective. Specifically, two exchange attributes, joint-specific investments and observability, can explain the emergence of accommodation. In addition, we examine the combined effect of competitive response strategies and cooperative response strategies on controlling partner opportunism. That is, competitive response strategies (i.e., monitoring) strengthen the governing effect of cooperative response strategies (i.e., accommodation).

Preliminary Data on a Sample of Perpetrators of Domestic Trafficking for Sexual Exploitation: Suggestions for Research and Practice

ABSTRACTTrafficking for sexual exploitation is one aspect of human trafficking and, in recent years, there has been an increased awareness of and focus on domestic trafficking for sexual exploitation within the United States; however, very little is known about the psychological characteristics or criminogenic (i.e., causing or likely to cause criminal behavior) risk/need factors of the perpetrators who profit from domestic trafficking for sexual exploitation. In an attempt to expand the scope of known data on perpetrators of domestic trafficking for sexual exploitation, descriptive statistical analyses looking at factors hypothesized to be related to the psychological characteristics, criminogenic risk/need factors, and potential treatment interventions were conducted on a sample of 28 adult male offenders with an arrest, charge, and/or conviction of street-level domestic trafficking for sexual exploitation behavior in their history. The results provide preliminary data regarding the developmental/environmental factors, psychological characteristics, and criminogenic risk/need factors of this offender population, as well as support the hypothesis that perpetrators of domestic trafficking for sexual exploitation behavior appear to be a unique offender population requiring specialized management and therapeutic interventions. Suggestions and implications for practice and research are also provided.

Extended maternal care and offspring interactions in the subsocial Australian crab spider, Xysticus bimaculatus

Extended maternal care is considered a prerequisite for the evolution of permanent family grouping and eusociality in invertebrates. In spiders, the essential evolutionary transitions to permanent sociality along this ‘subsocial route’ include the extension of care beyond hatching, the persistence of offspring groups to maturation and the elimination of premating dispersal. Subsocial Australian crab spiders (Thomisidae) present a suitable system to identify the selective agents prolonging group cohesion. Particularly, the recent discovery of independently evolved subsociality in the thomisid Xysticus bimaculatus provides new potential for comparative studies to expand the limited understanding of group cohesion beyond the offspring’s potential independence and despite socially exploitative behaviour. Providing fundamental knowledge, the present study investigated maternal care and offspring interactions in X. bimaculatus for the first time. Nest dissections revealed that mothers produce exceptionally small clutches, potentially reflecting a limit in the number of juveniles they can successfully care for. A laboratory experiment demonstrated crucial benefits for offspring in receiving maternal care beyond nutritional independence, mediated by extensive maternal food provisioning. However, prey-sharing also occurred between juveniles irrespective of maternal presence, which marks this species’ predisposition for exploitative feeding behaviour. I therefore suggest X. bimaculatus as a suitable model for investigating the regulation of communal feeding in group-living spiders.

The Effect of Rail Fastening System Modifications on Tram Traffic Noise and Vibration

Tram system is a backbone of public transportation in the City of Zagreb. In the last decade, its fleet has been renewed by 142 new low-floor trams. Shortly after their introduction, it was observed that they have a negative impact on the exploitation behavior of tram infrastructure, primarily on the durability of rail fastening systems. Because of that, it was decided to modify existing rail fastening systems to the new track exploitation conditions. When the (re)construction of tram infrastructure is carried out by applying new systems and technologies, it is necessary to take into account their impact on the future propagation of noise and vibration in the environment. This paper gives a short overview of the characteristics of the two newly developed rail fastening systems for Zagreb tram tracks, their application in construction of experimental track section, and performance and comparison of noise and vibration measurements results. Measured data on track vibrations and noise occurring during passage of the tram vehicles is analyzed in terms of track decay rates and equivalent noise levels of passing referent vehicle. Vibroacoustic performance of new fastening systems is evaluated and compared to referent fastening system, in order to investigate their ability to absorb vibration energy induced by tram operation and to reduce noise emission.