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排序方式: 共有638条查询结果,搜索用时 15 毫秒
1.
This study back-tests a marginal cost of production model proposed to value the digital currency Bitcoin. Results from both conventional regression and vector autoregression (VAR) models show that the marginal cost of production plays an important role in explaining Bitcoin prices, challenging recent allegations that Bitcoins are essentially worthless. Even with markets pricing Bitcoin in the thousands of dollars each, the valuation model seems robust. The data show that a price bubble that began in the Fall of 2017 resolved itself in early 2018, converging with the marginal cost model. This suggests that while bubbles may appear in the Bitcoin market, prices will tend to this bound and not collapse to zero.  相似文献   
2.
The paper investigates whether patent fees are an effective mechanism to deter the filing of low‐quality patent applications. The study analyzes the effect on patent quality of the Patent Law Amendment Act of 1982, which resulted in a substantial increase in patenting fees at the U.S. Patent and Trademark Office. Results from a series of difference‐in‐differences regressions suggest that the increase in fees led to a weeding out of low‐quality patents. About 10% of patents in the lowest quality decile were filtered out, with the effect concentrated in the patents of firms whose overall patent portfolio was medium to large (more than 20 patents). The study has strong policy implications in the current context of concerns about declines in patent quality.  相似文献   
3.
The first 150 words of the full text of this article appear below. The year 1982 was not a particularly good period for the worldeconomy. At year's end, the Organization for Economic Cooperationand Development (OECD) revised its growth figures for membernations from slightly over 1% to –0.5%, with some 32 millionunemployed in its 24 member states. In the United States thejobless rate was 11% and 30% of plant capacity stood idle. OttoEckstein found the economy in its worst shape in nearly halfa century. Truly the year belonged to Scrooge. Yet 1982 was a very good year indeed for financial econometrics,the debut of an explosion of activity in the area that continuesvigorously 20 years later, as the emergence of the Journal ofFinancial Econometrics attests. In fact, it can convincinglybe argued that 1982 heralded the beginning of our subject, andperhaps with the recent awarding of the Nobel Prize in Economicsto Robert Engle . . . [Full Text of this Article]  相似文献   
4.
Two transitions in the evolution of the social contract are considered, the first from the dominance hierarchies of the great apes (used as a proxy for our prehuman ancestors) to the egalitarian political structure of non-sedentary hunter-gatherer bands, and the second, to the reintroduction of hierarchical institutions of governance, primarily a result of living in fixed settlements after the inception of agriculture. The first transition was a product of biological and cultural evolution, which brought about big brains, language, higher consciousness, and a lower rate of time preference that enabled early man to sustain an egalitarian social contract and thereby escape the domination that confronted his prehuman ancestors. The second transition was a product of cultural evolution alone. The high costs of enforcing the hunter-gatherer social contract caused it to break down and be replaced by hierarchy when the domestication of plants and animals gave rise to a sedentary existence and increased populations. However, it is shown that the very biological and cultural adaptations that made hunter-gatherer egalitarianism possible were a necessary foundation for the spontaneous creation of complex culture and the evolution of institutions that would once again eventually make freedom possible and economic prosperity possible.  相似文献   
5.
This paper uses a real option approach to analyze the impact of alternative marketing contracts on the decision to invest in a cooperatively owned hog facility. For the numerical analysis of the impact, this paper uses a simulation method that incorporates early exercise, multiple‐state variables, multi‐choice decisions and temporal optimality. The results show that the option values that stem from the value of waiting to invest and choosing between alternative marketing methods amounts to 20–36% of the initial investment. Further, having an option to choose an alternative marketing method with different risk structure does add to the value of waiting to invest. Having an option to enter a 15‐year marketing contract increases the value of waiting by as much as $117,097 for the pork production example in this paper. Finally, the value of the option to wait is unilaterally lower under a risk‐reducing contract scenario than under a spot market alternative. This could explain the explosion in hog production facility investment during the 1990s when prevalence of contract production increased. Les auteurs ont recouru à l'approche du choix véritable pour analyser l'impact d'autres solutions de mise en marché sur la capacité d'investir ou pas dans un élevage de porcs exploitéà la manière d'une coopérative. Aux fins de l'analyse, on s'est servi d'une méthode de simulation intégrant une brève campagne, de multiples variables d'État, des décisions à choix multiple et des conditions optimales dans le temps. Les résultats indiquent que l'existence d'un choix réel permettant à l'exploitant d'attendre avant d'investir et de sélectionner entre plusieurs méthodes de mise en marché représente 20 à 36 pour cent de l'investissement initial. Par ailleurs, le fait d'avoir accès à une autre méthode de mise en marché, à structure de risque différente, ne donne pas plus de valeur à la capacité d'attendre avant de procéder aux investissements. La possibilité de signer une entente de commercialisation de quinze ans accroît la valeur de l'attente de jusqu'à 117,097 $ pour le type d'élevage porcin retenu comme exemple. Enfin, l'existence d'une entente de commercialisation atténuant les risques réduit unilatéralement la valeur de l'option « attente », comparativement à ce qui se produit quand l'éleveur n'a d'autre choix qu'écouler ses bêtes sur le marché au comptant. Ces résultats pourraient expliquer l'explosion des investissements observée dans le secteur du porc au cours des années 90, où la production sous contrat avait sensiblement augmenté.  相似文献   
6.
Earlier studies of the seigniorage inflation model have found that the high-inflation steady state is not stable under learning. We reconsider this issue and analyze the full set of solutions for the linearized model. Our main focus is on stationary hyperinflationary paths near the high-inflation steady state. These paths are shown to be stable under least-squares learning if agents can utilize contemporaneous data. In an economy with a mixture of agents, some of whom only have access to lagged data, stable hyperinflationary paths emerge only if the proportion of agents with access to contemporaneous data is sufficiently high.  相似文献   
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8.
ABSTRACT

In this paper a novel information model that can be used in Manufacturing Execution Systems is presented. The model is based on the fusion of ISA95, AML and OPC UA. ISA95 is used to define, unify and describe the details of a product and production technology. It also enables communication with ERP systems. The AML standard allows information about the production facilities to be presented. The OPC UA address space represents different parts of an information model while the OPC communication protocol enables it to be linked to actual production systems. The proposed concept is illustrated using an actual example of a production line for electronic devices.  相似文献   
9.
We ask what redistributions of income and assets are feasible in a democracy, given the initial assets and their distribution. The question is motivated by the possibility that if redistribution is insufficient for the poor or excessive for the rich, they may turn against democracy. In turn, if no redistribution simultaneously satisfies the poor and the wealthy, democracy cannot be sustained. Hence, the corollary question concerns the conditions under which democracy is sustainable. We find that democracies survive in wealthy societies. Conditional on the initial income distribution and the capacity of the poor and the wealthy to overthrow democracy, each country has a threshold of capital stock above which democracy survives. This threshold is lower when the distribution of initial endowments is more equal and when the revolutionary prowess of these groups is lower. Yet in poor unequal countries there exist no redistribution scheme which would be accepted both by the poor and the wealthy. Hence, democracy cannot survive. As endowments increase, redistribution schemes that satisfy both the poor and the wealthy emerge. Moreover, as capital stock grows the wealthy tolerate more and the poor less redistribution, so that the set of feasible redistributions becomes larger. Since the median voter prefers one such scheme to the dictatorship of either group, democracy survives.We would like to thank, Daron Acemoglu, Marco Basetto, Alberto Bisin, V.V. Chari, Pat Kehoe, Onur Ozgur for very useful comments.  相似文献   
10.
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