Search results for " multipliers"
showing 10 items of 17 documents
An Adaptive Alternating Direction Method of Multipliers
2021
AbstractThe alternating direction method of multipliers (ADMM) is a powerful splitting algorithm for linearly constrained convex optimization problems. In view of its popularity and applicability, a growing attention is drawn toward the ADMM in nonconvex settings. Recent studies of minimization problems for nonconvex functions include various combinations of assumptions on the objective function including, in particular, a Lipschitz gradient assumption. We consider the case where the objective is the sum of a strongly convex function and a weakly convex function. To this end, we present and study an adaptive version of the ADMM which incorporates generalized notions of convexity and penalty…
Operators on Partial Inner Product Spaces: Towards a Spectral Analysis
2014
Given a LHS (Lattice of Hilbert spaces) $V_J$ and a symmetric operator $A$ in $V_J$, in the sense of partial inner product spaces, we define a generalized resolvent for $A$ and study the corresponding spectral properties. In particular, we examine, with help of the KLMN theorem, the question of generalized eigenvalues associated to points of the continuous (Hilbertian) spectrum. We give some examples, including so-called frame multipliers.
Statistics of transitions for Markov chains with periodic forcing
2013
The influence of a time-periodic forcing on stochastic processes can essentially be emphasized in the large time behaviour of their paths. The statistics of transition in a simple Markov chain model permits to quantify this influence. In particular the first Floquet multiplier of the associated generating function can be explicitly computed and related to the equilibrium probability measure of an associated process in higher dimension. An application to the stochastic resonance is presented.
Effects of Fiscal Stimulus in Structural Models
2010
The paper assesses, using seven structural models used heavily by policymaking institutions, the effectiveness of temporary fiscal stimulus. Models can, more easily than empirical studies, account for differences between fiscal instruments, for differences between structural characteristics of the economy, and for monetary-fiscal policy interactions. Findings are: (i) There is substantial agreement across models on the sizes of fiscal multipliers. (ii) The sizes of spending and targeted transfers multipliers are large. (iii) Fiscal policy is most effective if it has some persistence and if monetary policy accommodates it. (iv) The perception of permanent fiscal stimulus leads to significant…
Analysis of compressor architectures in MOS current-mode logic
2010
This paper is concerned with the design and the comparison of different compressor architectures for high performance multipliers in MOS current-mode logic (MCML). More specifically, three architectures have been designed for 3-2, 4-2 and 5-2 compressors and two architectures for 7-2 compressors. The various implementations for each type of compressor have been compared one another. This investigation indicates that the architectures based exclusively on three-level MCML gates are the most suitable for MCML implementation in terms of speed, power consumption and area. Design guidelines are provided to improve compressor performance. All the compressors were designed in a TSMC 180nm CMOS tec…
Household Leverage and Fiscal Multipliers
2011
We study the size of fiscal multipliers in response to a government spending shock under different household leverage conditions in a general equilibrium setting with search and matching frictions. We allow for different levels of household indebtedness by changing the intensive margin of borrowing (loan-to-value ratio), as well as the extensive margin, defined as the number of borrowers over total population. The interaction between the consumption decisions of agents with limited access to credit and the process of wage bargaining and vacancy posting delivers two main results: (a) higher initial leverage makes it more likely to find output multipliers higher than one; and (b) a positive g…
Testing and implementing a new approach to estimating interregional output multipliers using input-output data for South Korean regions
2020
Flegg's location quotient (FLQ) is a useful tool for estimating intraregional output multipliers. This paper uses it as one component when estimating interregional multipliers. Using statistical information criteria and official data for 16 South Korean regions, it is found that the best approach is to combine the FLQ with a simple trade model. The paper explains how the proposed procedure can be implemented for both multiple and individual regions, and also how a region-specific value for the unknown parameter δ in the FLQ formula can be determined. Finally, an illustrative case study of one of the regions is carried out.
Nonlocal model of Superfluid Turbulence: Constitutive Theory
2014
In this paper, the constitutive restrictions for the fluxes in a nonlocal model of superfluid turbulence are deduced from the entropy principle, using the Liu method of Lagrange multipliers. The proposed model chooses as fundamental fields the density, the velocity, the energy density, the heat flux, and the averaged vortex line length per unit volume. The onstitutive quantities are assumed to depend on the fundamental fields and on their first derivative.
A New Augmented Lagrangian Approach for $L^1$-mean Curvature Image Denoising
2015
Variational methods are commonly used to solve noise removal problems. In this paper, we present an augmented Lagrangian-based approach that uses a discrete form of the L1-norm of the mean curvature of the graph of the image as a regularizer, discretization being achieved via a finite element method. When a particular alternating direction method of multipliers is applied to the solution of the resulting saddle-point problem, this solution reduces to an iterative sequential solution of four subproblems. These subproblems are solved using Newton’s method, the conjugate gradient method, and a partial solution variant of the cyclic reduction method. The approach considered here differs from ex…
Instruments, rules, and household debt: the effects of fiscal policy
2015
In this paper, we look at the interplay between the level of household leverage in the economy and fiscal policy, the latter characterised by different combinations of instruments and rules. When the fiscal rule is defined on lump-sum transfers, government spending or consumption taxes, the impact multipliers of transitory fiscal shocks become substantially amplified in an environment of easy access to credit by impatient consumers, regardless of the primary instruments used. However, when the government reacts to debt deviations by raising distortionary taxes on income, labour or capital, the effects of household debt on the size of the impact output multipliers vanish or even reverse, no …