Results 41 to 50 of about 46,949 (225)

Intraday Functional PCA Forecasting of Cryptocurrency Returns

Journal of Forecasting, EarlyView.
ABSTRACT We study the functional PCA (FPCA) forecasting method in application to functions of intraday returns on Bitcoin. We show that improved interval forecasts of future return functions are obtained when the conditional heteroscedasticity of return functions is taken into account.
Joann Jasiak, Cheng Zhong
wiley   +1 more source

On the Open Problem Related to Rank Equalities for the Sum of Finitely Many Idempotent Matrices and Its Applications

The Scientific World Journal, 2014
Tian and Styan have shown many rank equalities for the sum of two and three idempotent matrices and pointed out that rank equalities for the sum P1+⋯+Pk with P1,…,Pk be idempotent (k>3) are still open.
Mei-xiang Chen, Qing-hua Chen, Qiao-xin Li, Zhong-peng Yang   +3 more
doaj   +1 more source

Study Some Properties of a Circulant Matrix

Tikrit Journal of Pure Science, 2023
The aim of this paper is to study the properties of idempotent, nilpotent and stability to a circulant matrix  which generated by the first row, finally we showed the relation between this properties with eigenvalues of this matrix.
Akram Salim Mohammed
doaj   +1 more source

Nonnegative Idempotent Matrices [PDF]

Proceedings of the American Mathematical Society, 1974
Elementary ideas in the theory of partially ordered linear algebras are used to describe the structure of nonnegative idempotent matrices. In particular, we obtain a kind of “spectral decomposition” theorem for such matrices.
openaire   +2 more sources

Band‐Pass Filtering With High‐Dimensional Time Series. A Synthetic Indicator of the Medium‐to‐Long Run Component of Growth

Journal of Time Series Analysis, EarlyView.
ABSTRACT The paper deals with the construction of a synthetic indicator of economic growth, obtained by projecting a quarterly measure of aggregate economic activity, namely gross domestic product (GDP), into the space spanned by a finite number of smooth principal components, representative of the medium‐to‐long‐run component of economic growth of a ...
Alessandro Giovannelli, Marco Lippi, Tommaso Proietti   +2 more
wiley   +1 more source

Can we repudiate ontology altogether?

Noûs, EarlyView.
Abstract Ontological nihilists repudiate ontology altogether, maintaining that ontological structure is an unnecessary addition to our theorizing. Recent defenses of the view involve a sophisticated combination of highly expressive but ontologically innocent languages combined with a metaphysics of features—non‐objectual, complete but modifiable states
Christopher J. Masterman
wiley   +1 more source

A Collapse Result in the Mereology of Properties

Ratio, EarlyView.
ABSTRACT I examine five principles about the metaphysics of properties, each of which has been defended in the literature: (1) the sum of properties is their corresponding conjunctive property, (2) the mereology of properties is classical, (3) properties are individuated by necessary co‐instantiation, (4) sums of objects belonging to different ...
Alejandro G. Di Rienzo
wiley   +1 more source

The Equivalent Standard Forms of a Class of Tropical Matrices and Centralizer Groups

Mathematics
In this paper, the equivalent standard forms of tropical idempotent strongly definite matrices are introduced. In particular, the observation of the equivalent standard forms of tropical idempotent normal matrices is given.
Yanliang Cheng
doaj   +1 more source

Direct products of cyclic semigroups and left zero semigroups in $\beta\mathbb{N}$ [PDF]

Categories and General Algebraic Structures with Applications
We show that for every $n\in\mathbb{N}$, the direct product of the cyclic semigroup of order $n$ and period $1$ and the left zero semigroup $2^\mathfrak{c}$ has copies in $\beta\mathbb{N}$.
Yuliya Zelenyuk
doaj   +1 more source

Recursive and Cyclic Constructions for Double‐Change Covering Designs

Journal of Combinatorial Designs, Volume 34, Issue 4, Page 198-209, April 2026.
ABSTRACT A double‐change covering design (DCCD) is a v‐set V and an ordered list L of b blocks of size k where every pair from V must occur in at least one block and each pair of consecutive blocks differs by exactly two elements. It is minimal if it has the fewest blocks possible and circular when the first and last blocks also differ by two elements.
Amanda Lynn Chafee, Brett Stevens
wiley   +1 more source