Results 61 to 70 of about 1,430 (227)

A Note on ⊕-Cofinitely Supplemented Modules

International Journal of Mathematics and Mathematical Sciences, 2007
Let R be a ring and M a right R-module. In this note, we show that a quotient of an ⊕-cofinitely supplemented module is not in general ⊕-cofinitely supplemented and prove that if a module M is an ⊕-cofinitely supplemented multiplication module with Rad(M)
Yongduo Wang, Qing Sun
doaj   +1 more source

New estimation methods for diagnostic classification models

British Journal of Mathematical and Statistical Psychology, EarlyView.
Abstract This paper introduces a new class of estimators for cognitive diagnosis models (CDMs) based on the Cressie–Read family of ϕ$$ \phi $$‐divergences. Focusing on the loglinear CDM (LCDM), for which joint maximum likelihood estimation (JMLE) has been shown to be consistent, we propose a joint minimum divergence estimation (JMDE) framework.
Elena Castilla
wiley   +1 more source

When some complement of an exact fully invariant submodule is a direct summand [PDF]

In this paper, we study modules with the property that every exact fully invariant submodule has a complement which is a direct summand. This new class of modules properly contains both of classes of FI-extending modules and C11r-modules (i.e.
Yücel, Canan Celep, Tercan, Adnan, CELEP YÜCEL, CANAN   +2 more
core   +1 more source

The Decentralization of Liquor Policies in Texas During the Post‐Prohibition Era

International Economic Review, EarlyView.
ABSTRACT We examine the decentralization of liquor policies in Texas during the Post‐Prohibition era using newly collected historical legislative roll call data. By combining these data with local referendum vote shares, we analyze both legislators' and constituents' preferences on liquor policy.
Andrew Arnold, Holger Sieg
wiley   +1 more source

Testing for Unspecified Periodicities in Binary Time Series

Journal of Time Series Analysis, EarlyView.
ABSTRACT Given random variables Y1,…,Yn$$ {Y}_1,\dots, {Y}_n $$ with Yi∈{0,1}$$ {Y}_i\in \left\{0,1\right\} $$ we test the hypothesis whether the underlying success probabilities pi$$ {p}_i $$ are constant or whether they are periodic with an unspecified period length of r≥2$$ r\ge 2 $$.
Finn Schmidtke, Mathias Vetter
wiley   +1 more source

When is a Discrete Bounded Subgroup of an LCA Group Necessarily a Topological Direct Summand? [PDF]

, 2000
We establish necessary and sufficient conditions for a discrete bounded subgroup of an LCA (locally compact abelian) group to be a topological direct summand.
Loth, Peter
core  

On Selection of Cross‐Section Averages in Non‐Stationary Environments

Journal of Time Series Analysis, EarlyView.
ABSTRACT Information criteria (ICs) have been widely used in factor models to estimate an unknown number of latent factors. It has recently been shown that ICs perform well in Common Correlated Effects (CCE) and related settings when selecting a set of cross‐section averages (CAs) sufficient for the factor space under stationary factors.
Jan Ditzen, Ovidijus Stauskas
wiley   +1 more source

MODULES WHOSE CLOSED SUBMODULES WITH ESSENTIAL SOCLE ARE DIRECT SUMMANDS [PDF]

, 2014
We introduce and study CLESS-modules, which subsume two generalizations of extending modules due to P.F. Smith and A. Tercan. A module M will be called a CLESS-module if every closed submodule N of M (in the sense that M/N is non-singular) with essential
Sahinkaya, Serap, Crivei, Septimiu
core   +1 more source

A Note on Local Polynomial Regression for Time Series in Banach Spaces

Journal of Time Series Analysis, EarlyView.
ABSTRACT This work extends local polynomial regression to Banach space‐valued time series for estimating smoothly varying means and their derivatives in non‐stationary data. The asymptotic properties of both the standard and bias‐reduced Jackknife estimators are analyzed under mild moment conditions, establishing their convergence rates.
Florian Heinrichs
wiley   +1 more source

Purely Goldie Extending Modules

Ibn Al-Haitham Journal for Pure and Applied Sciences, 2017
An -module  is extending if every submodule of   is essential in a direct summand of . Following Clark, an -module  is purely extending if every submodule of   is essential in a pure submodule of .
Saad A. Al-Saadi, Ikbal A. Omer
doaj