排序方式: 共有53条查询结果,搜索用时 15 毫秒
41.
The literature predicts that the average skill level and productivity are higher in larger cities. Prior studies use workers’ wage or education differentials to indirectly link city size and output. This article relates city size and productivity directly, using performance data of U.S. equity mutual funds. On average, funds in financial centers perform better than other funds in terms of both gross and risk-adjusted returns, but this difference is driven only by more experienced managers. Among funds in financial centers there is strong evidence of a positive relation between performance and manager experience in a given city, especially among New York funds. More importantly, we observe performance improvements of the same manager at the same fund in financial centers but not elsewhere. Our tests provide novel evidence of knowledge spillovers and learning in cities. 相似文献
42.
43.
This paper presents a simple discrete time model for valuing real options. A short and simple proof of optimal exercise rules for the standard problems in the real options theory is given in the binomial and trinomial models, and, more generally, when the underlying uncertainty is modelled as a random walk on a lattice. The method of the paper is based on the use of the expected present value operators. With straightforward modifications, the method works in discrete time-continuous space, continuous time-continuous space and continuous time-discrete space models. 相似文献
44.
Conditional Probabilistic Population Forecasting 总被引:1,自引:0,他引:1
Warren C. Sanderson Sergei Scherbov Brian C. O'Neill Wolfgang Lutz 《Revue internationale de statistique》2004,72(2):157-166
Since policy-makers often prefer to think in terms of alternative scenarios, the question has arisen as to whether it is possible to make conditional population forecasts in a probabilistic context. This paper shows that it is both possible and useful to make these forecasts. We do this with two different kinds of examples. The first is the probabilistic analog of deterministic scenario analysis. Conditional probabilistic scenario analysis is essential for policy-makers because it allows them to answer "what if" type questions properly when outcomes are uncertain. The second is a new category that we call "future jump-off date forecasts". Future jump-off date forecasts are valuable because they show policy-makers the likelihood that crucial features of today's forecasts will also be present in forecasts made in the future. 相似文献
45.
Continuous time models in the theory of real options give explicit formulas for optimal exercise strategies when options are simple and the price of an underlying asset follows a geometric Brownian motion. This article suggests a general, computationally simple approach to real options in discrete time. Explicit formulas are derived even for embedded options. Discrete time processes reflect the scarcity of observations in the data, and may account for fat tails and skewness of probability distributions of commodity prices. The method of this article is based on the use of the expected present value operators. 相似文献
46.
EFFICIENT PRICING OF BARRIER OPTIONS AND CREDIT DEFAULT SWAPS IN LÉVY MODELS WITH STOCHASTIC INTEREST RATE 下载免费PDF全文
Recently, advantages of conformal deformations of the contours of integration in pricing formulas for European options have been demonstrated in the context of wide classes of Lévy models, the Heston model, and other affine models. Similar deformations were used in one‐factor Lévy models to price options with barrier and lookback features and credit default swaps (CDSs). In the present paper, we generalize this approach to models, where the dynamics of the assets is modeled as , where X is a Lévy process, and the interest rate is stochastic. Assuming that X and r are independent, and , the infinitesimal generator of the pricing semigroup in the model for the short rate, satisfies weak regularity conditions, which hold for popular models of the short rate, we develop a variation of the pricing procedure for Lévy models which is almost as fast as in the case of the constant interest rate. Numerical examples show that about 0.15 second suffices to calculate prices of 8 options of same maturity in a two‐factor model with the error tolerance and less; in a three‐factor model, accuracy of order 0.001–0.005 is achieved in about 0.2 second. Similar results are obtained for quanto CDS, where an additional stochastic factor is the exchange rate. We suggest a class of Lévy models with the stochastic interest rate driven by 1–3 factors, which allows for fast calculations. This class can satisfy the current regulatory requirements for banks mandating sufficiently sophisticated credit risk models. 相似文献
47.
48.
Internet auctions with many traders 总被引:4,自引:0,他引:4
We study a multi-unit auction environment similar to eBay. Sellers, each with a single unit of a homogeneous good, set reserve prices at their own second-price auctions. Each buyer has private value for the good and wishes to acquire a single unit. Buyers can bid as often as they like and move between auctions. We characterize a perfect Bayesian equilibrium for this decentralized dynamic mechanism in which, conditional on reserve prices, an efficient set of trades occurs at a uniform price. In a large but finite market, the sellers set reserve prices equal to their true costs under a very mild distributional assumption, so ex post efficiency is achieved. Buyers’ strategies in this equilibrium are simple and do not depend on their beliefs about other buyers’ valuations, or the number of buyers and sellers. 相似文献
49.
The “transition happiness gap” has been one of the most robust findings in the literature on life satisfaction. Until very recently, scholars using various datasets have shown that residents of post-communist countries were significantly less satisfied with their lives than their counterparts in non-transition countries (controlling for income and other socio-economic characteristics). The literature has explained this finding by the great macroeconomic instability of the 1990s, by a substantial decrease in the quality and accessibility of public goods, by the major increase in inequality, and by the rapid depreciation of pre-transition human capital. All these factors were expected to subside over time – at least after the post-Great-Recession recovery. In this paper, we consider two most recent datasets – the third wave of the Life in Transition Survey (administered in 2015–16) and the 2010–2016 waves of the annual Gallup World Poll. We find that by 2016 the transition happiness gap had closed. This convergence has taken place both due to a “happiness recovery” in post-communist countries after the Great Recession and due to a decrease in life satisfaction in comparator countries in recent years. We also find that the convergence in life satisfaction was primarily driven by middle-income young, educated individuals, regardless of gender. 相似文献
50.
ABSTRACTThe purpose of this paper is to assess the major trends, factors, and prospects of development of Russian and EEU sunflower oil exports. The sanctions resulted in an increase of sunflower oil exports in 2014 to a peak value, which allowed the producers to accumulate revenues in hard currency. The gravity models findings for Russia and for the EEU show that the sanctions stimulated the growth of sunflower oil exports. As distinct from a common language, a common border also encourages the development of Eurasian exports to third countries. The tariff size in the importer country is strongly and negatively connected with exports both from Russia and from the EEU. The effect of regional integration within the EEU is insignificant for the development of sunflower oil exports, while regional integration processes in the CIS have a positive impact on exports. 相似文献