85 resultados para Nicolás Factor , Beato, 1520-1583-Culto-València
Spanning tests in return and stochastic discount factor mean-variance frontiers: A unifying approach
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We propose new spanning tests that assess if the initial and additional assets share theeconomically meaningful cost and mean representing portfolios. We prove their asymptoticequivalence to existing tests under local alternatives. We also show that unlike two-step oriterated procedures, single-step methods such as continuously updated GMM yield numericallyidentical overidentifyng restrictions tests, so there is arguably a single spanning test.To prove these results, we extend optimal GMM inference to deal with singularities in thelong run second moment matrix of the influence functions. Finally, we test for spanningusing size and book-to-market sorted US stock portfolios.
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This paper presents new estimates of total factor productivity growth in Britain for the period1770 1860. We use the dual technique and argue that the estimates we derive from factorprices are of similar quality to quantity-based calculations. Our results provide further evidence,calculated on the basis of an independent set of sources, that productivity growth duringthe British Industrial Revolution was relatively slow. The Crafts Harley view of theIndustrial Revolution is thus reinforced. Our preferred estimates suggest a modest accelerationafter 1800.
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This paper presents several applications to interest rate risk managementbased on a two-factor continuous-time model of the term structure of interestrates previously presented in Moreno (1996). This model assumes that defaultfree discount bond prices are determined by the time to maturity and twofactors, the long-term interest rate and the spread (difference between thelong-term rate and the short-term (instantaneous) riskless rate). Several newmeasures of ``generalized duration" are presented and applied in differentsituations in order to manage market risk and yield curve risk. By means ofthese measures, we are able to compute the hedging ratios that allows us toimmunize a bond portfolio by means of options on bonds. Focusing on thehedging problem, it is shown that these new measures allow us to immunize abond portfolio against changes (parallel and/or in the slope) in the yieldcurve. Finally, a proposal of solution of the limitations of conventionalduration by means of these new measures is presented and illustratednumerically.
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In this paper we consider the equilibrium effects of an institutionalinvestor whose performance is benchmarked to an index. In a partialequilibrium setting, the objective of the institutional investor is modeledas the maximization of expected utility (an increasing and concave function,in order to accommodate risk aversion) of final wealth minus a benchmark.In equilibrium this optimal strategy gives rise to the two-beta CAPM inBrennan (1993): together with the market beta a new risk-factor (that wecall active management risk) is brought into the analysis. This new betais deffined as the normalized (to the benchmark's variance) covariancebetween the asset excess return and the excess return of the market overthe benchmark index. Different to Brennan, the empirical test supports themodel's predictions. The cross-section return on the active management riskis positive and signifficant especially after 1990, when institutionalinvestors have become the representative agent of the market.
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We show how, in general equilibrium models featuring increasing returns, imperfectcompetition and endogenous markups, changes in the scale of economic activity affectincome distribution across factors. Whenever final goods are gross-substitutes (gross-complements), a scale expansion raises (lowers) the relative reward of the scarce factoror the factor used intensively in the sector characterized by a higher degree of product differentiation and higher fixed costs. Under very reasonable hypothesis, our theory suggests that scale is skill-biased. This result provides a microfoundation for the secular increase in the relative demand for skilled labor. Moreover, it constitutes an important link among major explanations for the rise in wage inequality: skill-biased technical change, capital-skill complementarities and international trade. We provide new evidence on the mechanism underlying the skill bias of scale.
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This paper presents a two--factor model of the term structure ofinterest rates. We assume that default free discount bond prices aredetermined by the time to maturity and two factors, the long--term interestrate and the spread (difference between the long--term rate and theshort--term (instantaneous) riskless rate). Assuming that both factorsfollow a joint Ornstein--Uhlenbeck process, a general bond pricing equationis derived. We obtain a closed--form expression for bond prices andexamine its implications for the term structure of interest rates. We alsoderive a closed--form solution for interest rate derivatives prices. Thisexpression is applied to price European options on discount bonds andmore complex types of options. Finally, empirical evidence of the model'sperformance is presented.
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In cost-effectiveness analysis (CEA) it is usually assumed that a QALY is of equal value to everybody, irrespective of the patient's age. However, it is possible that society assigns different social values to a QALY according to who gets it. In this paper we discuss the possibility of weighting health benefits for age in CEA. We also examinethe possibility that age-related preferences depend on the size of the health gain. An experiment was performedto test these hypotheses. The results assessing suggest that the patient's age is a relevant factor when assessing health gains.
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Aquest estudi pretén mostrar com una cort perifèrica dins de la monarquia espanyola com la dels Centelles, comtes d’Oliva, tot imitant fil per randa la dels Este de Ferrara i la seva brillant presència en la Itàlia renaixentista mitjançant el mecenatge de Boiardo i d’Ariosto, va importar aquells esquemes i es va envoltar d’un grup d’escriptors que van constituir el nucli inicial de la recepció, difusió i continuació castellana de l’èpica d’Ariosto a la península Ibèrica. Gairebé es podria afirmar que la propagació en castellà de l’Orlando furioso a la península Ibèrica estava monopolitzada en gran part pel clan dels Centelles. Un cercle en el qual localitzem, segons tots els indicis, el traductor de Gli asolani de Bembo al castellà: Lluís Santàngel
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In liberalized electricity markets, generation Companies must build an hourly bidthat is sent to the market operator. The price at which the energy will be paid is unknown during the bidding process and has to be forecast. In this work we apply forecasting factor models to this framework and study its suitability.
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Podeu consultar la versió en castellà a: http://hdl.handle.net/2445/16864
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Podeu consultar la versió en català a: http://hdl.handle.net/2445/16818
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The epidermal growth factor receptor (EGFR) is a member of the tyrosine kinase receptor family involved in signal transduction and the regulation of cellular proliferation and differentiation. It is also a calmodulin-binding protein. To examine the role of calmodulin in the regulation of EGFR, the effect of calmodulin antagonist, W-13, on the intracellular trafficking of EGFR and the MAPK signaling pathway was analyzed. W-13 did not alter the internalization of EGFR but inhibited its recycling and degradation, thus causing the accumulation of EGF and EGFR in enlarged early endosomal structures. In addition, we demonstrated that W-13 stimulated the tyrosine phosphorylation of EGFR and consequent recruitment of Shc adaptor protein with EGFR, presumably through inhibition of the calmodulin-dependent protein kinase II (CaM kinase II). W-13¿mediated EGFR phosphorylation was blocked by metalloprotease inhibitor, BB94, indicating a possible involvement of shedding in this process. However, MAPK activity was decreased by W-13; dissection of this signaling pathway showed that W-13 specifically interferes with Raf-1 activity. These data are consistent with the regulation of EGFR by calmodulin at several steps of the receptor signaling and trafficking pathways.