Results 41 to 50 of about 1,153 (175)
The Mathematical History Behind the Granger–Johansen Representation Theorem
Oxford Bulletin of Economics and Statistics, EarlyView.ABSTRACT When can a vector time series that is integrated once (i.e., becomes stationary after taking first differences) be described in error correction form? The answer to this is provided by the Granger–Johansen representation theorem. From a mathematical point of view, the theorem can be viewed as essentially a statement concerning the geometry of ...
Johannes M. Schumacher
wiley +1 more source
A discrete form of Jordan curve theorem [PDF]
, 1993 The paper includes purely cobinatorial proof of a theorem that implies the following theorem, stated by Hugo Steinhaus in [6, p.35]: consider a chessboard (rectang:ular, not necessarily square) with some "mined" squares on.
Surówka, Wojciech
core +2 more sources
Two Discrete Forms of the Jordan Curve Theorem
, 1988 The Jordan curve theorem is one of those frustrating results in topology: it is intuitively clear but quite hard to prove. In this note we will look at two discrete analogs of the Jordan curve theorem that are easy to prove by an induction argument ...
Stout, Lawrence, Lawrence Neff Stout
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Threshold Regression for Fixed‐T$$ T $$ Panel Data with Interactive Fixed Effects
Oxford Bulletin of Economics and Statistics, EarlyView.ABSTRACT This paper develops a new toolbox for estimation and inference in panel data threshold regression models with interactive fixed effects and a fixed number of time periods, T$$ T $$. The toolbox is designed to be simple, accurate, and computationally efficient.
Jan Ditzen +2 more
wiley +1 more source
A converse to the Jordan curve theorem for digital curves
Information and Control, 1975 It is shown that a subset S of a digital picture is a simple closed curve if and only if its complement S¯ has exactly two components, and every point of S is adjacent to both of these components.
openaire +1 more source
Analytic Philosophy, EarlyView.ABSTRACT I defend the non‐instrumentalist thesis that every adult member of a political society has a pro tanto fundamental moral right to an equal democratic say in determining the content of the laws to which she is subject. I begin by giving an account of an important kind of servility that has received only glancing notice in philosophical ...
Shruta Swarup
wiley +1 more source
Jordan curve theorem : different approaches [PDF]
, 2019 RESUMEN: Se conocen muchas demostraciones del teorema de la curva de Jordan. A lo largo de éste trabajo desarrollamos en detalle algunas de estas pruebas.
Revilla Martín, Eloy
core
A Survey for Deep Reinforcement Learning Based Network Intrusion Detection
Applied AI Letters, Volume 7, Issue 2, June 2026.This paper surveys deep reinforcement learning (DRL) for network intrusion detection, evaluating model efficiency, minority attack detection, and dataset imbalance. Findings show DRL achieves state‐of‐the‐art results on public datasets, sometimes surpassing traditional deep learning.
Wanrong Yang +3 more
wiley +1 more source
Automorphism groups of P1$\mathbb {P}^1$‐bundles over geometrically ruled surfaces
Journal of the London Mathematical Society, Volume 113, Issue 6, June 2026.Abstract We classify the pairs (X,π)$(X,\pi)$, where π:X→S$\pi \colon X\rightarrow S$ is a P1$\mathbb {P}^1$‐bundle over a non‐rational geometrically ruled surface S$S$ and Aut∘(X)$\mathrm{Aut}^\circ (X)$ is relatively maximal, that is, maximal with respect to the inclusion in the group Bir(X/S)$\mathrm{Bir}(X/S)$.
Pascal Fong
wiley +1 more source
A nonstandard proof of the Jordan curve theorem
, 1996 A new elementary nonstandard proof of the Jordan curve theorem is given. The proof (the technical part consists of 4 pages) is self-contained, except for the Jordan theorem for polygons taken for granted.
Kanovei, Vladimir, Reeken, Michael
openaire +4 more sources