1,721,084 research outputs found
Dynamic game under ambiguity: the sequential bargaining example, and a new "coase conjecture"
No full textConventional Bayesian games of incomplete information are limited in their ability to represent severe incompleteness of information. Using an illustrative example of (seller offer) sequential bargaining with one-sided incomplete information, we analyze a dynamic game under ambiguity. The novelty of our model is the stark assumption that the seller has complete ignorance---represented by the set of all plausible prior distributions---over the buyer's type. We propose a new equilibrium concept---Perfect Objectivist Equilibrium (POE)---in which multiple priors and full Bayesian updating characterize the belief system, and the uninformed player maximizes the infimum expected utility over non-weakly-dominated strategies. We provide a novel justification for refining POE through Markov perfection, and obtain a unique refined equilibrium. This results in a New "Coase Conjecture"---a competitive outcome arising from an apparent monopoly, which does not require the discount rate to approach zero, and is robust to reversion caused by reputation equilibria
Subsidizing research programs with "if" and "when" uncertainty in the face of severe informational constraints
No full textWe study government optimal subsidy policies for research programs in the face of servere information asymmetry---when firms have private information about the likelihood of project viability but the government cannot form a unique prior belief about this likelihood. The paper makes two contributions. First, we show that the way in which R&D is subsidized matters. Under both monopoly R&D (i.e., a single firm conducts R&D in isolation) and R&D competition, different types of subsidies (e.g., earmarked, unrestricted subsidies, and pure matching subsidies) have significantly different effects on firms' R&D investment incentives. Second, we show that a simple subsidy scheme works even when the government is unable to form a unique prior belief about the firm's private information on project viability. If the shadow cost of public funds is zero, under monopoly R&D, there exists a pure matching subsidy that induces the firm to follow the first-best R&D policy irrespective of its prior beliefs about the viability of the project, meaning it is a (belief-free) ex post equilibrium policy; under R&D competition, the first-best outcome can also be achieved through a simple combination of a matching subsidy and an unrestricted subsidy. If the shadow cost of public funds is positive, an ex post equilibrium in general does not exist either under monopoly or competition. We then consider two alternative policy decision criteria that are appropriate for belief-free games: rationalizability and max-min criteria. We argue that the max-min criteria is preferable in our context, and by way of doing so establish that the set of max-min subsidy policies under either monopoly or competitive R&D consists entirely of simple pure matching subsidies. We further establish that allowing firms to form an R&D consortium reduces the matching rate for the highest max-min subsidy, suggesting that cooperative R&D has the potential to economize on the shadow costs of public funding of subsidies
A Dynamic Game under Ambiguity: Repeated Bargaining with Interactive Learning
No full textConventional Bayesian games of incomplete information are limited in their ability to represent complete ignorance of an uninformed player about an opponent's private information. Using an illustrative example of repeated bargaining with interactive learning, we analyze a dynamic game of incomplete information that incorporates a multiple-prior belief system. We consider a game in which a principal sequentially compensates an agent for his effort on a novel experiment --- a Poisson process with unknown hazard rate. The agent has knowledge to form a single prior over the hazard rate, but the principal has complete ignorance, represented by the set of all plausible prior distributions over the hazard rate. We propose a new equilibrium concept --- Perfect Objectivist Equilibrium --- in which the principal infers the agent's prior from the observed history of the game via maximum likelihood updating. The new equilibrium concept embodies a novel model of learning under ambiguity in the context of a dynamic game. The unique (Markov) equilibrium outcome determines a unique bargaining solution. The underlying Markov Perfect Objectivist Equilibria are all belief-free, in sharp contrast to Markov Perfect Bayesian Equilibria, which hinge on subjective pretense of knowledge and predict a continuum of equilibrium outcomes
Subsidizing research programs with “if” and “when” uncertainty in the face of severe informational constraints
No full textWe study subsidy policies for research programs when firms have private information about the likelihood of project viability, but the government cannot form a unique prior about this likelihood. When the shadow cost of public funds is zero, first-best welfare can be attained as a (belief-free) ex post equilibrium under both monopoly and competition, but it cannot be attained when the shadow cost is positive. However, max-min subsidy policies exist under monopoly and competition and consist of pure matching subsidies. Under a Research and Development (R&D) consortium, the highest max-min matching rate is lower than under competition, and R&D investment intensity is higher.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
