Results 41 to 50 of about 523 (140)
Moments of exit times from wedges for non-homogeneous random walks with asymptotically zero drifts [PDF]
, 2013 We study quantitative asymptotics of planar random walks that are spatially non-homogeneous but whose mean drifts have some regularity. Specifically, we study the first exit time $\tau_\alpha$ from a wedge with apex at the origin and interior half-angle $
MacPhee, I.M. +4 more
core +2 more sources
Multiple Chains Markov Switching Vector Autoregression
Journal of Time Series Analysis, EarlyView.ABSTRACT Both the U.S. stock and bond returns exhibit distinct Markovian regimes. However, because these regimes display limited coherence, conventional models typically require highly parameterized systems to adequately capture their joint distribution.
Leopoldo Catania
wiley +1 more source
Penalized Convex Estimation in Dynamic Location Models
Journal of Time Series Analysis, EarlyView.ABSTRACT This paper studies L1$$ {L}^1 $$‐penalized estimation for location models yt=mt+ϵt$$ {y}_t={m}_t+{\epsilon}_t $$, where mt$$ {m}_t $$ is defined by a possibly non‐Markovian recursion and ϵt$$ {\epsilon}_t $$ is a martingale difference sequence with possibly time‐varying conditional variance.
Reda Alami Chentoufi
wiley +1 more source
Detecting Periodicity of a General Stationary Time Series via AR(2)‐Model Fitting
Journal of Time Series Analysis, EarlyView.ABSTRACT Estimating the periodicity of a stationary time series via fitting a second‐order stationary autoregressive (AR(2)) model has been initiated by the seminal paper of Yule (1927). We investigate properties of this procedure when applied to general stationary processes possessing a spectral density with a dominant peak at some unknown frequency ...
Jens‐Peter Kreiss +2 more
wiley +1 more source
Likelihood Estimation for Stochastic Differential Equations with Mixed Effects
Scandinavian Journal of Statistics, EarlyView.ABSTRACT Stochastic differential equations provide a powerful tool for modelling dynamic phenomena affected by random noise. When time series are observed for several experimental units, it is often the case that some of the parameters vary between the individual experimental units.
Fernando Baltazar‐Larios +2 more
wiley +1 more source
Transience and non-explosion of certain stochastic Newtonian systems [PDF]
, 2002 We give sufficient conditions for non-explosion and transience of the solution (xt,pt) (in dimensions >= 3) to a stochastic Newtonian system of the form { dxdt = ptdt dpt = -δV(xt)/δx dt - δc(xt)/δx dξt where {ξt}t>=0 is a d-dimensional Lévy process,
Kolokoltsov, V. N. (Vasiliĭ Nikitich) +2 more
core
Invariant Measure and Universality of the 2D Yang–Mills Langevin Dynamic
Communications on Pure and Applied Mathematics, Volume 79, Issue 8, Page 1973-2102, August 2026.ABSTRACT We prove that the Yang–Mills (YM) measure for the trivial principal bundle over the two‐dimensional torus, with any connected, compact structure group, is invariant for the associated renormalised Langevin dynamic. Our argument relies on a combination of regularity structures, lattice gauge‐fixing and Bourgain's method for invariant measures ...
Ilya Chevyrev, Hao Shen
wiley +1 more source
Power bounded composition operators on spaces of analytic functions [PDF]
, 2010 We study the dynamical behaviour of composition operators defined on spaces of real analytic functions. We characterize when such operators are power bounded, i.e. when the orbits of all the elements are bounded. In this case this condition is equivalent
José Bonet +3 more
core +1 more source
Lost in Translation? Risk‐Adjusting RMSE for Economic Forecast Performance
Journal of Forecasting, Volume 45, Issue 5, Page 2587-2605, August 2026.ABSTRACT When used for parameter optimization and/or model selection, traditional mean squared error (MSE)–based measures of forecast accuracy often exhibit a weak or even negative correlation with the economic value of return forecasts measured by, for example, the Sharpe ratios of the resulting portfolios.
Lukas Salcher +2 more
wiley +1 more source
Inference on Common Trends in a Cointegrated Nonlinear SVAR
Oxford Bulletin of Economics and Statistics, Volume 88, Issue 4, Page 658-676, August 2026.ABSTRACT We consider the problem of performing inference on the number of common stochastic trends when data is generated by a cointegrated CKSVAR (a two‐regime, piecewise affine SVAR; Mavroeidis, 2021), using a modified version of the Breitung (2002) multivariate variance ratio test that is robust to the presence of nonlinear cointegration (of a known
James A. Duffy, Xiyu Jiao
wiley +1 more source