scholarly journals The evolution of moral rules in a model of indirect reciprocity with private assessment

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Cedric Perret ◽  
Marcus Krellner ◽  
The Anh Han

AbstractMoral rules allow humans to cooperate by indirect reciprocity. Yet, it is not clear which moral rules best implement indirect reciprocity and are favoured by natural selection. Previous studies either considered only public assessment, where individuals are deemed good or bad by all others, or compared a subset of possible strategies. Here we fill this gap by identifying which rules are evolutionary stable strategies (ESS) among all possible moral rules while considering private assessment. We develop an analytical model describing the frequency of long-term cooperation, determining when a strategy can be invaded by another. We show that there are numerous ESSs in absence of errors, which however cease to exist when errors are present. We identify the underlying properties of cooperative ESSs. Overall, this paper provides a first exhaustive evolutionary invasion analysis of moral rules considering private assessment. Moreover, this model is extendable to incorporate higher-order rules and other processes.

2018 ◽  
Vol 194 ◽  
pp. 188-192
Author(s):  
D. I. Shokasheva

Natural populations of crayfish are in depression in Russia and local species are not cultivated. In this situation, experimental cultivation of allochtonous australian crayfish Cherax quadricarinatus is conducted. This species is distinguished by high reproductive abilities and good consumer properties. It has domesticated in Russia spontaneously and produced 9–10 generations in Astrakhan Region. Certain natural selection in the process of domestication provides adaptive ability of this species to local environments and its capabil­ity to reproduce a viable progeny, so there is no doubts in good prospects of its cultivation in industrial conditions.


Sports ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 85
Author(s):  
Lee Bell ◽  
Alan Ruddock ◽  
Tom Maden-Wilkinson ◽  
Dave Hembrough ◽  
David Rogerson

Optimal physical performance is achieved through the careful manipulation of training and recovery. Short-term increases in training demand can induce functional overreaching (FOR) that can lead to improved physical capabilities, whereas nonfunctional overreaching (NFOR) or the overtraining syndrome (OTS) occur when high training-demand is applied for extensive periods with limited recovery. To date, little is known about the OTS in strength sports, particularly from the perspective of the strength sport coach. Fourteen high-performance strength sport coaches from a range of strength sports (weightlifting; n = 5, powerlifting; n = 4, sprinting; n = 2, throws; n = 2, jumps; n = 1) participated in semistructured interviews (mean duration 57; SD = 10 min) to discuss their experiences of the OTS. Reflexive thematic analysis resulted in the identification of four higher order themes: definitions, symptoms, recovery and experiences and observations. Additional subthemes were created to facilitate organisation and presentation of data, and to aid both cohesiveness of reporting and publicising of results. Participants provided varied and sometimes dichotomous perceptions of the OTS and proposed a multifactorial profile of diagnostic symptoms. Prevalence of OTS within strength sports was considered low, with the majority of participants not observing or experiencing long-term reductions in performance with their athletes.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Sebastian Contreras ◽  
Jonas Dehning ◽  
Matthias Loidolt ◽  
Johannes Zierenberg ◽  
F. Paul Spitzner ◽  
...  

AbstractWithout a cure, vaccine, or proven long-term immunity against SARS-CoV-2, test-trace-and-isolate (TTI) strategies present a promising tool to contain its spread. For any TTI strategy, however, mitigation is challenged by pre- and asymptomatic transmission, TTI-avoiders, and undetected spreaders, which strongly contribute to ”hidden" infection chains. Here, we study a semi-analytical model and identify two tipping points between controlled and uncontrolled spread: (1) the behavior-driven reproduction number $${R}_{t}^{H}$$ R t H of the hidden chains becomes too large to be compensated by the TTI capabilities, and (2) the number of new infections exceeds the tracing capacity. Both trigger a self-accelerating spread. We investigate how these tipping points depend on challenges like limited cooperation, missing contacts, and imperfect isolation. Our results suggest that TTI alone is insufficient to contain an otherwise unhindered spread of SARS-CoV-2, implying that complementary measures like social distancing and improved hygiene remain necessary.


1998 ◽  
Vol 7 (1) ◽  
pp. 7-20 ◽  
Author(s):  
K Greenawalt

The author lays a blueprint for distinctions between legal and moral rules and socially accepted behavior, situations in which these distinctions set different standards of conduct, and the relationship among them. Several of the more common paradigms of cultural property disputes are then fit into the patterns of legal and moral rules and obligations, thus establishing a framework for the discussion of how to evaluate ethical or moral behaviors in varying circumstances. The author also considers the relevance of deontological and consequentialist arguments for the return of cultural property, as well as avoidance strategies by which a country of origin can make a claim for restitution while ignoring the long-term questions of the legitimacy, power, and responsibilities of national governments. The author concludes by emphasizing the difficulties in basing arguments concerning cultural property on moral evaluations and conclusions.


Author(s):  
Caitlin N Cadaret ◽  
Dustin T Yates

Abstract Studies show that retrieval practices such as homework assignments that are completed during the encoding phase of learning benefit knowledge acquisition and retention. In addition, desirable difficulties, which are strategies that intentionally create a greater challenge during initial learning to enhance encoding and retrieval pathways, also benefit learning long term. Our objective was to determine whether weekly homework questions intended to create desirable difficulties by requiring higher-order cognitive skills (HOCS) benefited students’ long-term retention of physiology concepts compared to questions designed to require lower-order cognitive skills (LOCS). Undergraduate students in a junior-level animal physiology course were presented information during weekly laboratory periods, and then required to complete retrieval practices in the form of online homework assignments 5 d after each lab. Homework questions were formatted per Bloom’s Taxonomy to require HOCS (i.e. level 4 or 5) or LOCS (i.e. level 1 or 2). Information retention was assessed the next week via performance on an in-class quiz and again at semesters’ end via performance on a final practical exam. We observed no differences in performance on the in-class quiz or final practical exam between students randomly assigned to complete homework with HOCS questions compared to LOCS questions. However, students that received homework with HOCS questions had decreased (P < 0.05) performance scores on 9 out of the 11 homework assignments compared to those receiving homework with LOCS questions. These findings indicate that desirable difficulties were not created by our HOCS homework questions because students receiving these more difficult retrieval practices did not achieve equal success on them. As a result, this attempt to create variations in cognitive demand did not enhance retention of knowledge in this study.


2015 ◽  
Vol 25 (6) ◽  
pp. 744-776 ◽  
Author(s):  
Apostolos Giovanis ◽  
Pinelopi Athanasopoulou ◽  
Evangelos Tsoukatos

Purpose – The purpose of this paper is to extend the well-established nomological network of service quality-relationship quality-customer loyalty by introducing service fairness – a distinct service evaluation concept. Specifically, the study aims to investigate the impact of service fairness on relationship quality as a complementary to service quality driver, and the direct and indirect effect of service fairness on customer loyalty in the presence of service quality and relationship quality in a no failure/recovery effort service context. Design/methodology/approach – A telephone survey of a random sample of 408 customers of auto repair and maintenance services was implemented using a structured questionnaire with established scales. Data were analyzed with partial least squares path methodology, a structural equation modeling methodology. Findings – Interactional fairness is the most important formative determinant of customers’ overall fairness perception, followed by procedural and distributive fairness. Relationship quality measured as a higher order construct, made of satisfaction; trust; affective and calculative commitment, is the main determinant of customer loyalty. Also, it partially mediates, along with service quality, the relationship between service fairness and customer loyalty and fully mediates the effect of service quality on customer loyalty. Finally, service fairness has the highest overall effect on customer loyalty. Research limitations/implications – The sample is industry-specific and this may affect generalizability of findings. Also, the cross-sectional design adopted does not reflect temporal changes. Practical implications – Interactional fairness is of utmost importance to customers of the investigated industry. So, customers should be fairly treated at every point of contact. Also, service quality is heavily affected by service fairness. Thus, fair service leads to high-perceived service quality. Third, service quality affects customer loyalty only through relationship quality. Only when service quality is coupled by long-term quality relationships, signs of customer loyalty appear. Finally, service fairness influences customer loyalty mainly through service and relationship quality and has the highest overall effect on customer loyalty. So, fairly treating customers is crucial for developing long-term relationships that lead to customer loyalty. Originality/value – The role of service fairness in the service quality-relationship quality-customer loyalty chain is investigated and using a higher order construct for relationship quality.


Paleobiology ◽  
1985 ◽  
Vol 11 (1) ◽  
pp. 120-138 ◽  
Author(s):  
Daniel C. Fisher

Many questions have emerged recently regarding the importance and methodology of analysis of adaptation. Divergent views reflect both problems of definition and more substantive issues of interpretation. Defining the state of adaptation in terms of its contribution to current fitness, rather than origin by natural selection, is essential if natural selection is to be considered anexplanationof adaptation. The context dependency and relativity of fitness apply also to adaptation. Design criteria are essential components of adaptation, but only to the extent that they are subsumed as elements of the causal interactions determining relative reproductive potential. The local, relational, contingent character of adaptation supports only limited reference to improvement. Most long-term patterns of change can be better described as diffusion within a structured design-space than as progressive improvement of design. The analysis of adaptation is part of a broader inquiry into the processes and constraints that control form and the history of changing form. It offers one perspective on how organisms operate on ecological time scales and how their configurations might be maintained or transformed over evolutionary time. Hypotheses concerning adaptation are sometimes tested by reference to predictions concerning the central tendency or trend of some aspect of an anatomical-behavioral system. These can be interpreted with minimal reference to assumptions of optimality if the analysis is viewed in terms of Bayesian inference. However, an alternative and frequently preferable approach to testing relies on limit-oriented predictions. Analysis of adaptation can be visualized as inferring the pattern and nature of interactions comprising the causal plexus that determines fitness. A comprehensive understanding of form and form-change requires that this be integrated with the perspective offered by studies of development, genetics, phylogenetic history, and external perturbations acting on the system.


2018 ◽  
Vol 80 (2) ◽  
pp. 124-131 ◽  
Author(s):  
Emily A. Kane ◽  
E. Dale Broder ◽  
Andrew C. Warnock ◽  
Courtney M. Butler ◽  
A. Lynne Judish ◽  
...  

Evolution education poses unique challenges because students can have preconceptions that bias their learning. Hands-on, inquiry approaches can help overcome preset beliefs held by students, but few such programs exist and teachers typically lack access to these resources. Experiential learning in the form of self-guided kits can allow evolution education programs to maximize their reach while still maintaining a high-quality resource. We created an inquiry-based kit that uses live Trinidadian guppies to teach evolution by natural selection using the VIST (Variation, Inheritance, Selection, Time) framework. Our collaborative team included evolutionary biologists and education specialists, and we were able to combine expertise in evolution research and inquiry-based kit design in the development of this program. By constructing the kits with grant funds slated for broader impacts and maintaining them at our university's Education and Outreach Center, we made these kits freely available to local schools over the long term. Students and teachers have praised how clearly the kits teach evolution by natural selection, and we are excited to share this resource with readers of The American Biology Teacher.


2018 ◽  
Vol 6 (6) ◽  
pp. 532-551 ◽  
Author(s):  
Caichun Chai ◽  
Hailong Zhu ◽  
Zhangwei Feng

Abstract The management strategies of a firm are inevitable affected by individual behavior preferences. The effect of individual preference on the evolutionary dynamics for supply chains is studied by employing replicator dynamics. Each firm has three behavior preferences: selfishness, fairness, and altruism. Firstly, the case that the strategy set of manufacturers and retailers including two pure strategies is considered and the effect of preference parameter on the equilibrium outcome in the short-term interaction is discussed. Secondly, the equilibrium state in the short-term is always disturbed because the change of the environment, firm’s structure, and so forth. Using the replicator dynamics, the evolutionary stable strategies of manufacturers and retailers in the long-term interaction are analyzed. Finally, the extend case that the strategy set of manufacturers and retailers include three pure strategies is investigated. These results are found that the strategy profile in which both manufacturer and retailer choose fairness or altruism, or one player chooses fair or altruistic strategy and the other player chooses selfish strategy may be evolutionary stable, the stability of these equilibria depends on the the preference parameters.


2017 ◽  
Vol 13 (S337) ◽  
pp. 251-254
Author(s):  
A. Ridolfi ◽  
P. C. C. Freire ◽  
M. Kramer ◽  
C. G. Bassa ◽  
F. Camilo ◽  
...  

AbstractMulti-decade observing campaigns of the globular clusters 47 Tucanae and M15 have led to an outstanding number of discoveries. Here, we report on the latest results of the long-term observations of the pulsars in these two clusters. For most of the pulsars in 47 Tucanae we have measured, among other things, their higher-order spin period derivatives, which have in turn provided stringent constraints on the physical parameters of the cluster, such as its distance and gravitational potential. For M15, we have studied the relativistic spin precession effect in PSR B2127+11C. We have used full-Stokes observations to model the precession effect, and to constrain the system geometry. We find that the visible beam of the pulsar is swiftly moving away from our line of sight and may very soon become undetectable. On the other hand, we expect to see the opposite emission beam sometime between 2041 and 2053.


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