Results 151 to 160 of about 4,703 (266)

SCF Framework, HF Stability, and RPA Correlation for Jordan-Wigner-Transformed Spin Hamiltonians on Arbitrary Coupling Topologies. [PDF]

J Chem Theory Comput
Tabrizi SG, Henderson TM, Kühne TD, Scuseria GE.   +3 more
europepmc   +1 more source

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

Convex Hartree-Fock theory for modeling ground state conical intersections. [PDF]

Commun Chem
Rossi F, Koch H.
europepmc   +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

Moving Aggregate Modified Autoregressive Copula‐Based Time Series Models (MAGMAR‐Copulas)

Journal of Time Series Analysis, EarlyView.
ABSTRACT Copula‐based time series models can model univariate and stationary time series in a flexible way by decomposing the joint distribution of consecutive observations into a copula and the stationary distribution. Implicitly, this approach assumes a finite Markov order. In reality, a time series may not follow the Markov property.
Sven Pappert
wiley   +1 more source

A Two-Level Preconditioner for the CASSCF Linear-Response Equations. [PDF]

J Phys Chem A
Helmich-Paris B.
europepmc   +1 more source

Parametric Time‐Variation in the Unconditional Volatility: Estimation and Inference

Journal of Time Series Analysis, EarlyView.
ABSTRACT We propose modeling time‐variation in the unconditional volatility by augmenting the standard GARCH model by a deterministic time‐varying intercept. The model, called the additive time‐varying (ATV‐)GARCH model, can be interpreted as a reduced form of a model including covariates and can be derived from a multiplicative decomposition of ...
Niklas Ahlgren, Alexander Back, Timo Teräsvirta   +2 more
wiley   +1 more source

Freeze-and-Release Direct Optimization Method for Variational Calculations of Excited Electronic States. [PDF]

J Chem Theory Comput
Schmerwitz YLA, Selenius E, Levi G.
europepmc   +1 more source

Reinforcement Learning for Jump‐Diffusions, With Financial Applications

Mathematical Finance, EarlyView.
ABSTRACT We study continuous‐time reinforcement learning (RL) for stochastic control in which system dynamics are governed by jump‐diffusion processes. We formulate an entropy‐regularized exploratory control problem with stochastic policies to capture the exploration–exploitation balance essential for RL.
Xuefeng Gao, Lingfei Li, Xun Yu Zhou
wiley   +1 more source

Multi-physics modeling for ion homeostasis in multi-compartment plant cells using an energy function. [PDF]

PLoS Comput Biol
Mestdagh G, De Angeli A, Godin C.
europepmc   +1 more source