2,005 research outputs found
Riesz transform characterization of H^1 spaces associated with certain Laguerre expansions
For alpha>0 we consider the system l_k^{(alpha-1)/2}(x) of the Laguerre
functions which are eigenfunctions of the differential operator Lf
=-\frac{d^2}{dx^2}f-\frac{alpha}{x}\frac{d}{dx}f+x^2 f. We define an atomic
Hardy space H^1_{at}(X), which is a subspace of L^1((0,infty), x^alpha dx).
Then we prove that the space H^1_{at}(X) is also characterized by the Riesz
transform Rf=\sqrt{\pi}\frac{d}{dx}L^{-1/2}f in the sense that f\in H^1_{at}(X)
if and only if f,Rf \in L^1((0,infty),x^alpha dx)
Regulating privatized infrastructures and airport services
For a World Bank Institute course on transport privatization, the authors cover basic issues associated with the regulation of privatized airport infrastructure and services: 1) Economic characteristics of airport. Three types of activities are carried out in airports: essential operational services (aeronautical and non-aeronautical), handling services (aeronautical and non-aeronautical), and commercial activities. Demand for basic airport services is directly influenced by trip purpose. The two types of airline customers (business and leisure travelers) need different levels of flexibility and tend to travel at different times. Analyzing airport capacity (practical and saturation) under peak demand is essential to airport success. Among other important issues: runway cost, level and volume of service, pollution, congestion, and air traffic control. 2) Recent trends in the airport industry. The movement toward privatization may involve public ownership and private operation, including joint ventures; partial or majority divestiture; management contracts; and BOT (build-operate-transfer) schemes and variants, including BOOT (build-own-operate-transfer) schemes and LDO (lease-develop-operate) schemes. Or it may involve private ownership and operation. 3) Price regulation. Topics covered include traditional pricing policies'price regulation through an RPI-X formula; charges for congestion, noise, and other externalities; investment plans; and design of the regulatory system. 4) Regulation of quality in the industry. Topics covered: regulation of services to passengers (as measured by targets for check-in queues, immigration queues, baggage reclaim queues, concourse crowding, shopping, parking, and so on); fault repair times; average levels of passenger boarding and disembarkation and baggage delivery; safety; and investment obligation. 5) Performance indicators in the industry. Topics covered: strategic indicators and other financial indicators (including revenues), as well as indicators of cost, productivity, and quality of service.Transport and Trade Logistics,Public Sector Economics&Finance,Banks&Banking Reform,Environmental Economics&Policies,Decentralization,Roads&Highways,Airports and Air Services,Public Sector Economics&Finance,Banks&Banking Reform,Transport and Trade Logistics
Forecasting Inflation Forecast Errors
We evaluate inflation forecasts from the Survey of Professional Forecasters (SPF) of the Central Bank of Chile. Forecast errors for the period 2000-2008 show an excess of autocorrelation and a statistically significant bias at the end of the sample. We take advantage of the autocorrelation structure of the forecast errors to build new and more accurate inflation forecasts. We evaluate these new forecasts in an out-of-sample exercise. The new forecasts display important reductions in bias and Mean Square Prediction Error. Moreover, these reductions are, in general, statistically significant.
Chébli–Trimèche hypergroups and W-type spaces
AbstractThe generalized Fourier transformation associated with Chébli–Trimèche hypergroups is investigated in some spaces of W-type introduced by Gelfand and Shilov. It is established that this transformation is an isomorphism from the space WM,a onto the space WM×,1/a, where the function M and the parameter a determine the growth of the testing functions in the first space, and M× denotes the Young dual function of M. The translation operator and the convolution corresponding to this transform are also studied in this class of spaces
Calder\'on-Zygmund operators in the Bessel setting
We study several fundamental operators in harmonic analysis related to Bessel
operators, including maximal operators related to heat and Poisson semigroups,
Littlewood-Paley-Stein square functions, multipliers of Laplace transform type
and Riesz transforms. We show that these are (vector-valued) Calder\'on-Zygmund
operators in the sense of the associated space of homogeneous type, and hence
their mapping properties follow from the general theory.Comment: 21 page
Hankel Multipliers of Laplace Transform Type
In this paper we prove that the Hankel multipliers of Laplace transform type
on are of weak type (1,1). Also we analyze Lp-boundedness properties
for the imaginary powers of Bessel operator on .Comment: 32 page
UMD Banach spaces and the maximal regularity for the square root of several operators
In this paper we prove that the maximal -regularity property on the
interval , , for Cauchy problems associated with the square root of
Hermite, Bessel or Laguerre type operators on
characterizes the UMD property for the Banach space .Comment: 23 pages. To appear in Semigroup Foru
- …