The 0-1 inverse maximum stable set problem

Given an instance of a weighted combinatorial optimization problem and its feasible solution, the usual inverse problem is to modify as little as possible (with respect to a fixed norm) the given weight system to make the giiven feasible solution optimal. We focus on its 0-1 version, which is to modify as little as possible the structure of the given instance so that the fixed solution becomes optimal in the new instance. In this paper, we consider the 0-1 inverse maximum stable set problem against a specific (optimal or not) algorithm, which is to delete as few vertices as possible so that the fixed stable set S* can be returned as a solution by the given algorithm in the new instance. Firstly, we study the hardness and approximation results of the 0-1 inverse maximum stable set problem against the algorithms. Greedy and 2-opt. Secondly, we identify classes of graphs for which the 0-1 inverse maximum stable set problem can be polynomially solvable. We prove the tractability of the problem for several classes of perfect graphs such as comparability graphs and chordal graphs.Combinatorial inverse optimization, maximum stable set problem, NP-hardness, performance ratio, perfect graphs.

Inventory Changes With Information Asymmetry And Informed Trading Patterns In The Korean Stock Market

In this paper, we examine how inventory changes are related to the trading patterns of foreign and institutional investors, especially in firms with information asymmetry. Prior researchers report that inventory changes could be associated with firm performance, earnings management, stock returns, and incentive contracts. In this study, we focus on the relationship between trading patterns of informed traders and changes in inventory, testing how inventory changes are associated with the investment decision-making of informed traders. After controlling for firm-specific factors, we find a significant relationship between changes in inventory and trading patterns of institutional and foreign investors. Under conditions of high information asymmetry, the negative relation between institutional trading and inventory changes is enhanced. However, the amounts invested by foreign traders are negatively associated with increases in inventory even in firms with low information asymmetry. We infer that foreign traders exhibit more conservative trading patterns than institutional investors

Managing Complexity For Creating Breakthrough Inventions: Focusing On Collaboration Teams And Prior Art

Inventing processes are often greatly complex, resulting in the difficulty of creating breakthrough inventions. But the relationship between the complexity of inventing and the creation of breakthrough inventions and ways of dealing with the complexity of inventing have received little research attention. This study focuses on the effect of coupling, one of the causes of complex inventing, on the likelihood of creating breakthrough inventions and suggests two moderating factors: the size of collaboration teams and the oldness of prior art. Based on U.S. granted patents in optical disc technology domains applied during 1997–2001, the empirical results showed the negative effect of coupling on the likelihood of creating breakthrough patents and the weakening moderating effect of the number of inventors involved in generating patents

The 16th Data Release of the Sloan Digital Sky Surveys: First Release from the APOGEE-2 Southern Survey and Full Release of eBOSS Spectra

This paper documents the 16th data release (DR16) from the Sloan Digital Sky Surveys (SDSS), the fourth and penultimate from the fourth phase (SDSS-IV). This is the first release of data from the Southern Hemisphere survey of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2); new data from APOGEE-2 North are also included. DR16 is also notable as the final data release for the main cosmological program of the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), and all raw and reduced spectra from that project are released here. DR16 also includes all the data from the Time Domain Spectroscopic Survey and new data from the SPectroscopic IDentification of ERosita Survey programs, both of which were co-observed on eBOSS plates. DR16 has no new data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey (or the MaNGA Stellar Library "MaStar"). We also preview future SDSS-V operations (due to start in 2020), and summarize plans for the final SDSS-IV data release (DR17)

The 16th Data Release of the Sloan Digital Sky Surveys: First Release from the APOGEE-2 Southern Survey and Full Release of eBOSS Spectra

This paper documents the 16th data release (DR16) from the Sloan Digital Sky Surveys (SDSS), the fourth and penultimate from the fourth phase (SDSS-IV). This is the first release of data from the Southern Hemisphere survey of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2); new data from APOGEE-2 North are also included. DR16 is also notable as the final data release for the main cosmological program of the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), and all raw and reduced spectra from that project are released here. DR16 also includes all the data from the Time Domain Spectroscopic Survey and new data from the SPectroscopic IDentification of ERosita Survey programs, both of which were co-observed on eBOSS plates. DR16 has no new data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey (or the MaNGA Stellar Library "MaStar"). We also preview future SDSS-V operations (due to start in 2020), and summarize plans for the final SDSS-IV data release (DR17)

The 16th Data Release of the Sloan Digital Sky Surveys : First Release from the APOGEE-2 Southern Survey and Full Release of eBOSS Spectra

This paper documents the 16th data release (DR16) from the Sloan Digital Sky Surveys (SDSS), the fourth and penultimate from the fourth phase (SDSS-IV). This is the first release of data from the Southern Hemisphere survey of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2); new data from APOGEE-2 North are also included. DR16 is also notable as the final data release for the main cosmological program of the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), and all raw and reduced spectra from that project are released here. DR16 also includes all the data from the Time Domain Spectroscopic Survey and new data from the SPectroscopic IDentification of ERosita Survey programs, both of which were co-observed on eBOSS plates. DR16 has no new data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey (or the MaNGA Stellar Library "MaStar"). We also preview future SDSS-V operations (due to start in 2020), and summarize plans for the final SDSS-IV data release (DR17).Peer reviewe

Inverse combinatorial problems and applications

L'optimisation combinatoire inverse a suscité beaucoup d'attention de la communauté de la recherche opérationnelle pendant les deux dernières décennies. Étant donnée une instance d'un problème d'optimisation combinatoire définie par un système de paramètres (coûts, profits, etc.) et une solution réalisable, le problème inverse associé consiste à modifier au minimum les paramètres afin de rendre la solution fixée optimale dans l'instance modifiée. Dans le cadre de l'optimisation combinatoire, de nombreux problèmes inverses ont été étudiés, mais relativement peu d'études ont été menées sur des versions inverses de problèmes NP-difficiles. Dans cette thèse, nous considérons des problèmes combinatoires inverses généralisés. Nous commençons par imposer certaines contraintes aux paramètres à modifier. En particulier, des contraintes booléennes nous permettent de définir des versions inverses de problèmes non pondérés. Ainsi, des contraintes discrètes engendrent des problèmes combinatoires inverses eux-même combinatoires. Nous introduisons alors deux variantes de problèmes combinatoires inverses généralisés, à savoir "les problèmes inverses contre un algorithme spécifié" et "les problèmes inverses en valeur". Pour la première, un algorithme étant spécifié pour le problème d'origine, on cherche, pour une instance et une solution réalisable fixées, à modifier le moins possible l'instance pour que cette solution puisse être choisie par l'algorithme. Un problème inverse en valeur quant à lui est défini en spécifiant une valeur à atteindre au lieu d'une solution cible. L'objectif est de modifier le moins possible l'instance considerée de sorte que la valeur optimale de l'instance modifiée soit égale à la valeur fixée. Nous étudions différentes versions inverses de problèmes NP-difficiles. Les problèmes abordés sont le stable maximum d'un graphe (ensemble maximum de sommets 2 à 2 non adjacents), le voyageur de commerce minimum et la coloration minimum des sommets d'un graphe. Notre principal objectif est d'étudier la complexité et l'approximabilité de ces problèmes.PARIS1-BU Pierre Mendès-France (751132102) / SudocPARIS1-CNRS-Maison des sc. éco (751055202) / SudocSudocFranceF

The 0-1 inverse maximum stable set problem

In this paper we study the 0-1 inverse maximum stable set problem, denoted by I S{0, 1}. Given a graph and a fixed stable set, it is to delete the minimum number of vertices to make this stable set maximum in the new graph. We also consider I S{0, 1} against a specific algorithm such as G r e e d y and 2 o p t, aiming to delete the minimum number of vertices so that the algorithm selects the given stable set in the new graph; we denote them by I S{0, 1}, g r e e d y and I S{0, 1}, 2 o p t, respectively. Firstly, we show that they are NP-hard, even if the fixed stable set contains only one vertex. Secondly, we achieve an approximation ratio of 2 - Θ (frac(1, sqrt(l o g Δ))) for I S{0, 1}, 2 o p t. Thirdly, we study the tractability of I S{0, 1} for some classes of perfect graphs such as comparability, co-comparability and chordal graphs. Finally, we compare the hardness of I S{0, 1} and I S{0, 1}, 2 o p t for some other classes of graphs

Inverse chromatic number problems in interval and permutation graphs

International audienceGiven a graph G and a positive integer K, the inverse chromatic number problem consists in modifying the graph as little as possible so that it admits a chromatic number not greater than K. In this paper, we focus on the inverse chromatic number problem for certain classes of graphs. First, we discuss diverse possible versions and then focus on two application frameworks which motivate this problem in interval and permutation graphs: the inverse booking problem and the inverse track assignment problem. The inverse booking problem is closely related to some previously known scheduling problems; we propose new hardness results and polynomial cases. The inverse track assignment problem motivates our study of the inverse chromatic number problem in permutation graphs; we show how to solve in polynomial time a generalization of the problem with a bounded number of colors