We study the performance of heuristics relative to the performance of optimal solutions in the rich domain of sequential search, where the decision to stop the search depends only on the applicant’s relative rank. Considering multiple variants of the secretary problem, that vary from one another in their formulation and method of solution, we find that descriptive heuristics perform well only when the optimal solution prescribes a single threshold value. We show that a computational heuristic originally proposed as an approximate (...) solution to a single variant of the secretary problem performs equally well in many other variants where the optimal solution prescribes multiple threshold values that gradually relax the criterion for stopping the search. Finally, we propose a new heuristic with near optimal performance in a competitive or strategic variant of the secretary problem with multiple employers competing with one another to hire job applicants. Both heuristics share a simple computational component: the ratio of the number of interviewed applicants to the number of those remaining to be searched. We present the subgame-perfect Nash equilibrium for this competitive variant and an algorithm for its computation. (shrink)

The Braess Paradox (BP) is a counterintuitive finding that degrading a network that is susceptible to congestion may decrease the equilibrium travel cost for each of its users. We illustrate this paradox with two networks: a basic network with four alternative routes from a single origin to a single destination, and an augmented network with six alternative routes. We construct the equilibrium solutions to these two networks, which jointly give rise to the paradox, and subject them to experimental testing. Our (...) purpose is to test the generality of the BP when the network is enriched as well as the effects of the information provided to the network users when they conclude their travel. To this end, we compare experimentally two information conditions when each of the two networks is iterated in time. Under public monitoring each user is accurately informed of the route choices and payoffs of all the users, whereas under private monitoring she is only informed of her own payoff. Under both information conditions, over iterations of the basic and augmented games, aggregate route choices converge to equilibrium. (shrink)

Within the last decade, there has been a dramatic bloom in ridesharing businesses along with the emergence of new enabling technologies. A central issue in ridesharing, which is also important in the general domain of cost-sharing in economics and computer science, is that the sharing of cost implies positive externalities and hence coordination problems for the network users. We investigate these problems experimentally in the present study. In particular, we focus on how sequential observability of transportation mode choices can be (...) a powerful facilitator of coordination in ridesharing. Our study abstracts the essential issues of coordination in ridesharing into a directed network game with experimentally testable predictions. In line with the theoretical analysis, our experimental evidence shows that even a limited extent of sequential choice observability might lead to efficient coordination. However, convergence to efficiency is slower with more limited observability, resulting in a significant increase in travel cost. (shrink)

We consider a class of dynamic tournaments in which two contestants are faced with a choice between two courses of action. The first is a riskless option (“hold”) of maintaining the resources the contestant already has accumulated in her turn and ceding the initiative to her rival. The second is the bolder option (“roll”) of taking the initiative of accumulating additional resources, and thereby moving ahead of her rival, while at the same time sustaining a risk of temporary setback. We (...) study this tournament in the context of a jeopardy race game (JRG), extend the JRG to $N > 2$ contestants, and construct its equilibrium solution. Compared to the equilibrium solution, the results of three experiments reveal a dysfunctional bias in favor of the riskless option. This bias is substantially mitigated when the contestants are required to commit in advance how long to pursue the risky course of action. (shrink)

We examine the philosophical disputes among computer scientists concerning methodological, ontological, and epistemological questions: Is computer science a branch of mathematics, an engineering discipline, or a natural science? Should knowledge about the behaviour of programs proceed deductively or empirically? Are computer programs on a par with mathematical objects, with mere data, or with mental processes? We conclude that distinct positions taken in regard to these questions emanate from distinct sets of received beliefs or paradigms within the discipline: – The rationalist (...) paradigm, which was common among theoretical computer scientists, defines computer science as a branch of mathematics, treats programs on a par with mathematical objects, and seeks certain, a priori knowledge about their ‘correctness’ by means of deductive reasoning. – The technocratic paradigm, promulgated mainly by software engineers and has come to dominate much of the discipline, defines computer science as an engineering discipline, treats programs as mere data, and seeks probable, a posteriori knowledge about their reliability empirically using testing suites. – The scientific paradigm, prevalent in the branches of artificial intelligence, defines computer science as a natural (empirical) science, takes programs to be entities on a par with mental processes, and seeks a priori and a posteriori knowledge about them by combining formal deduction and scientific experimentation. We demonstrate evidence corroborating the tenets of the scientific paradigm, in particular the claim that program-processes are on a par with mental processes. We conclude with a discussion in the influence that the technocratic paradigm has been having over computer science. (shrink)

Singularity Hypotheses: A Scientific and Philosophical Assessment offers authoritative, jargon-free essays and critical commentaries on accelerating technological progress and the notion of technological singularity. It focuses on conjectures about the intelligence explosion, transhumanism, and whole brain emulation. Recent years have seen a plethora of forecasts about the profound, disruptive impact that is likely to result from further progress in these areas. Many commentators however doubt the scientific rigor of these forecasts, rejecting them as speculative and unfounded. We therefore invited prominent (...) computer scientists, physicists, philosophers, biologists, economists and other thinkers to assess the singularity hypotheses. Their contributions go beyond speculation, providing deep insights into the main issues and a balanced picture of the debate. (shrink)

Recent studies based on next‐generation DNA sequencing have revealed that the female inactive X chromosome is replicated in a rapid, unorganized manner, and undergoes increased rates of mutation. These observations link the organization of DNA replication timing to gene regulation on one hand, and to the generation of mutations on the other hand. More generally, the exceptional biology of the inactive X chromosome highlights general principles of genome replication. Cells may control replication timing by a combination of intrinsic replication origin (...) properties, local chromatin states and global levels of replication factors, leading to a functional separation between the activity of genes and their mutation. (shrink)

It remains to summarize the contributions which each of the three disciplines discussed here is making toward the development of a science of man. "Significs" makes a study of the effects on human behavior of the linguistic aspects of the evaluative process, the most distinctly human aspect of the behavior of the human organism. "Mathematical Biophysics" seeks to describe the events associated with evaluative processes in physico-mathematical terms. "Cybernetics" is discovering important invariants common to these processes and others, particularly those (...) observed in man-made machines and in situations which lend themselves to description in thermo-dynamic or statistical terms. (shrink)

Research studies on Corporate Social Responsibility often focus on revealing corporate leaders’ attitudes toward various issues of CSR. The position of the present paper is that to understand CSR, we must grasp the collaborative perspective of CSR, and discern the attitudes of community leaders as well as corporate leaders. To this end, the study compares attitudes of community leaders with those of corporate leaders in three localities in Israel. The study examines various issues of CSR, highlighting the benefits to both (...) community and corporation of reciprocal relations. Results from t‐tests confirmed significant differences between the groups. Some important implications for CSR particularly in terms of collaboration between community and corporation are discussed. (shrink)

This study seeks to provide a new resolution to an old controversy regarding Wilhelm Dilthey's methodological writings, written from 1880 to 1911. This controversy concentrates on the relations of Dilthey's early psychology and his late hermeneutics. On one side of this controversy stand interpreters who claim that the appearance of the late hermeneutics marks a dramatic change in Dilthey's thought, and even creates an internal paradox in his thinking. On the other side, stand interpreters who view his thought as a (...) unified whole, by claiming that these methods were meant to work in tandem and complement each other. I largely agree with the latter group of interpreters regarding the unity of Dilthey's writings; however, instead of basing my view on the methodological level of Dilthey’s writings, I will concentrate on the object of these two methods. According to my new answer to the question of the continuity of Dilthey’s thought, Dilthey did intend to replace his early psychology with his late hermeneutics; even so, his thought should still be viewed as consistent and stable because he continued to apply both different methods to the same object: inner-universal content, that is, the inner psychological source of outer human reality. In this way, I will try show that the consistency of Dilthey's thought is derived from the stable destination he aspired to reach with the help of the different methods. (shrink)

The essays included in the special issue dedicated to the philosophy of computer science examine new philosophical questions that arise from reflection upon conceptual issues in computer science and the insights such an enquiry provides into ongoing philosophical debates.

This study examines the sources of human divergence as arise from Wilhelm Dilthey’s writings. While Dilthey assigns a central role to the human subject, he never synthesizes his major ideas on subjectivity into a unified theory of subjective uniqueness. I will show that such a theory can be derived from his writings through the combination of three ideas that appear in them. These ideas are: (1) the thesis that human understanding is possible because of psychological content that is shared by (...) both the creator and the interpreter; (2) the belief that this shared content is the only content that exists within human beings, meaning that there is no unique psychological content; and (3) the perception of this inner universal content as an accumulation of life-possibilities. When joined together, these ideas create an inspiring theory of human divergence, according to which the uniqueness of an individual is determined through partial realization of universal possibilities. (shrink)

As our knowledge of the genetic constitution of human beings expands, testing to determine an individual's disposition toward a given disease will also increase. Since genes are a family affair, to know that an individual is genetically disposed toward a specific disease is an indicator that members of this individual's family may also be so disposed.

Over the past several decades, conflicts between physicians and patients or patient surrogates concerning continued treatment or the withdrawal of treatment have received public and legal attention. In more recent years, there have been several prominent Instances in which physicians have refused to provide treatment requested by patient surrogates because such treatment was judged to be futile. The claim that a treatment is futile has far reaching consequences. It serves to justify the withholding or withdrawal of treatment and thus, perhaps, (...) to also justify the rationing of healthcare. It limits the autonomy of the patient or patient surrogate by reducing their participation in the decision making process. (shrink)

Disease and illness are terms that are often used interchangeably by physicians and the lay public. But not all usage permits this. For instance, diseases are referred to in terms of entities with etiologies; illnesses are not. We also speak of illness as being the effect or symptom of a disease, but not the converse. In what follows, disease and illness will be treated as distinct concepts. a.

Because of the emphasis on individualism and self-governance, medical interventions and medical research in Western nations are preceded by attempts to obtain informed consent from the individual patient or potential research subject. Individual autonomy expresses our belief that persons are ends in themselves and not merely instrumentalities to achieve the goals of others. By respecting the patient or potential research subject in the context of medical decisionmaking, we acknowledge that these individuals are moral agents. Thus, individual autonomy is an important (...) feature of morality as it is practiced in the West. However, there are at least two circumstances in which individual autonomy appears to be threatened. One is embodied in nonwestern societies that favor collective decisionmaking over that of the individual. The other is related to the need for family histories and family testing to determine the susceptibility of family members to some genetically based disease. In both cases, individual judgment appears to be made subordinate to collective judgment. (shrink)

When Jean-Paul Sartre, the French existentialist philosopher, declared some four decades ago that man makes himself, this assertion was based on Sartre's belief that human beings do not possess an essential human nature. Man's self creation had to do with his freedom to choose the roles that he played or could play, and their attendant effects on his attitudes and responsibilities. It said nothing about his freedom to alter his biological nature.