arXiv subjects

Shao-Meng Qin

Publications and source records attributed to Shao-Meng Qin.

14 recordsLinked to original sources

arXiv2020

Network reconstruction from asynchronously updated evolutionary game

The interactions between players of prisoner's dilemma (PD) game are reconstructed with evolutionary game data. All participants play the game with their counterparts and gain corresponding rewards during each round of the game. However, their strategies are updated asynchronously during the evolutionary PD game. Two inference methods of the interactions between players are derived with naive mean-field (nMF) approximation and maximum log-likelihood estimation (MLE) respectively. The two methods are tested numerically also for fully connected asymmetric Sherrington-Kirkpatrick (SK) models, varying the data length, asymmetric degree, payoff and system noise (coupling strength). We find that the reconstruction mean square error (MSE) of MLE method is proportional to the inverse of data length and typically half (benefit from the extra information of update times) of that by nMF. Both methods are robust to the asymmetric degree but works better for large payoff. Compared with MLE, nMF is more sensitive to the couplings strength which prefers weak couplings.

physics.soc-ph↗

arXiv2018

Spin-glass model for the C-dismantling problem

C-dismantling (CD) problem aims at finding the minimum vertex set D of a graph G(V,E) after removing which the remaining graph will break into connected components with the size not larger than C. In this paper, we introduce a spin-glass model with C+1 integer-value states into the CD problem and then study the properties of this spin-glass model by the belief-propagation (BP) equations under the replica-symmetry ansatz. We give the lower bound $ρ_c$ of the relative size of D with finite C on regular random graphs and Erdos-Renyi random graphs. We find $ρ_c$ will decrease gradually with growing C and it converges to $ρ_\infty$ as C$\to\infty$. The CD problem is called dismantling problem when C is a small finite fraction of |V|. Therefore, $ρ_\infty$ is also the lower bound of the dismantling problem when |V|$\to\infty$. To reduce the computation complexity of the BP equations, taking the knowledge of the probability of a random selected vertex belonging to a remaining connected component with the size A, the original BP equations can be simplified to one with only three states when C$\to\infty$. The simplified BP equations are very similar to the BP equations of the feedback vertex set spin-glass model [H.-J.~Zhou, Eur. Phys. J. B 86, 455 (2013)]. At last, we develop two practical belief-propagation-guide decimation algorithms based on the original BP equations (CD-BPD) and the simplified BP equations (SCD-BPD) to solve the CD problem on a certain graph. Our BPD algorithms and two other state-of-art heuristic algorithms are applied on various random graphs and some real world networks. Computation results show that the CD-BPD is the best in all tested algorithms in the case of small C. But considering the performance and computation consumption, we recommend using SCD-BPD for the network with small clustering coefficient when C is large.

physics.soc-ph↗

arXiv2017

Dismantle a network efficiently during the entire process by a compound algorithm

The dismantling network problem only asks the minimal vertex set of a graph after removing which the remaining graph will break into connected components of sub-extensive size, but we should also consider the efficiency of intermediate states during the entire dismantling process, which is measured by the general performance R in this paper. In order to improve the general performance of the belief-propagation decimation (BPD) algorithm, we introduce a compound algorithm (CA) mixing the BPD and the node explosive percolation (NEP) algorithm. In this CA, the NEP algorithm will rearrange and optimize the head part of a dismantling sequence given by the BPD. Two ancestor algorithms are connected at the joint point where the general performance can be optimized. It dismantles a graph to small pieces as quickly as the BPD, and it is with the efficiency of the NEP during the entire dismantling process. We find that a wise joint point is where the BPD breaks the original graph to subgraphs no longer larger than the 1% of the original one. We refer the CA with this settled joint point as the fast CA and the fast CA is in the same complexity class with the BPD algorithm. The computation on some real-world instances also exhibits that using the fast CA to optimize the intermediate process of a dismantling algorithm is an effective approach.

physics.soc-ph↗

arXiv2016

Spin glass phase transitions in the random feedback vertex set problem

A feedback vertex set (FVS) of an undirected graph contains vertices from every cycle of this graph. Constructing a FVS of sufficiently small cardinality is very difficult in the worst cases, but for random graphs this problem can be efficiently solved after converting it into an appropriate spin glass model [H.-J. Zhou, Eur. Phys. J. B 86 (2013) 455]. In the present work we study the local stability and the phase transition properties of this spin glass model on random graphs. For both regular random graphs and Erdös-Rényi graphs we determine the inverse temperature $β_l$ at which the replica-symmetric mean field theory loses its local stability, the inverse temperature $β_d$ of the dynamical (clustering) phase transition, and the inverse temperature $β_c$ of the static (condensation) phase transition. We find that $β_{l}$, $β_{d}$, and $β_c$ change with the (mean) vertex degree in a non-monotonic way; $β_d$ is distinct from $β_c$ for regular random graphs of vertex degrees $K\geq 64$, while $β_d$ are always identical to $β_c$ for Erdös-Rényi graphs (at least up to mean vertex degree $c=512$). We also compute the minimum FVS size of regular random graphs through the zero-temperature first-step replica-symmetry-breaking mean field theory and reach good agreement with the results obtained on single graph instances by the belief propagation-guided decimation algorithm. Taking together, this paper presents a systematic theoretical study on the energy landscape property of a spin glass system with global cycle constraints.

cond-mat.stat-mech↗

arXiv2014

Topological invariant tensor renormalization group method for spin glasses

Tensor renormalization group method (TRG) is a real space renormalization group approach. It has been successfully applied to both classical and quantum systems. In this paper, we study a disordered and frustrated system, the two-dimensional Edward-Anderson model, by a new topological invariant TRG scheme. We propose an approach to calculate the local magnetizations and nearest pair correlations simultaneously. The Nishimori multi-critical point predicted by the topological invariant TRG agrees well with the recent Monte-Carlo results. The TRG schemes outperform the mean field methods on the calculation of the partition function. We notice that it maybe obtain a negative partition function at sufficiently low temperatures. However, the negative contribution can be neglected if the systems is large enough. This topological invariant TRG can also be used to study three-dimensional spin glass systems.

cond-mat.dis-nn↗

arXiv2014

Solving the undirected feedback vertex set problem by local search

An undirected graph consists of a set of vertices and a set of undirected edges between vertices. Such a graph may contain an abundant number of cycles, then a feedback vertex set (FVS) is a set of vertices intersecting with each of these cycles. Constructing a FVS of cardinality approaching the global minimum value is a optimization problem in the nondeterministic polynomial-complete complexity class, therefore it might be extremely difficult for some large graph instances. In this paper we develop a simulated annealing local search algorithm for the undirected FVS problem. By defining an order for the vertices outside the FVS, we replace the global cycle constraints by a set of local vertex constraints on this order. Under these local constraints the cardinality of the focal FVS is then gradually reduced by the simulated annealing dynamical process. We test this heuristic algorithm on large instances of Erödos-Renyi random graph and regular random graph, and find that this algorithm is comparable in performance to the belief propagation-guided decimation algorithm.

cs.AI↗

arXiv2012

Patterns, entropy, and predictability of human mobility and life

Cellular phones are now offering an ubiquitous means for scientists to observe life: how people act, move and respond to external influences. They can be utilized as measurement devices of individual persons and for groups of people of the social context and the related interactions. The picture of human life that emerges shows complexity, which is manifested in such data in properties of the spatiotemporal tracks of individuals. We extract from smartphone-based data for a set of persons important locations such as "home", "work" and so forth over fixed length time-slots covering the days in the data-set. This set of typical places is heavy-tailed, a power-law distribution with an exponent close to -1.7. To analyze the regularities and stochastic features present, the days are classified for each person into regular, personal patterns. To this are superimposed fluctuations for each day. This randomness is measured by "life" entropy, computed both before and after finding the clustering so as to subtract the contribution of a number of patterns. The main issue, that we then address, is how predictable individuals are in their mobility. The patterns and entropy are reflected in the predictability of the mobility of the life both individually and on average. We explore the simple approaches to guess the location from the typical behavior, and of exploiting the transition probabilities with time from location or activity A to B. The patterns allow an enhanced predictability, at least up to a few hours into the future from the current location. Such fixed habits are most clearly visible in the working-day length.

physics.soc-ph↗

arXiv2009

Four-state rock-paper-scissors games on constrained Newman-Watts networks

We study the cyclic dominance of three species in two-dimensional constrained Newman-Watts networks with a four-state variant of the rock-paper-scissors game. By limiting the maximal connection distance $R_{max}$ in Newman-Watts networks with the long-rang connection probability $p$, we depict more realistically the stochastic interactions among species within ecosystems. When we fix mobility and vary the value of $p$ or $R_{max}$, the Monte Carlo simulations show that the spiral waves grow in size, and the system becomes unstable and biodiversity is lost with increasing $p$ or $R_{max}$. These results are similar to recent results of Reichenbach \textit{et al.} [Nature (London) \textbf{448}, 1046 (2007)], in which they increase the mobility only without including long-range interactions. We compared extinctions with or without long-range connections and computed spatial correlation functions and correlation length. We conclude that long-range connections could improve the mobility of species, drastically changing their crossover to extinction and making the system more unstable.

q-bio.PE↗

arXiv2009

Coevolution of game and network structure: The temptation increases the cooperator density

Most papers about the evolutionary game on graph assume the statistic network structure. However, social interaction could change the relationship of people. And the changing social structure will affect the people's strategy too. We build a coevolutionary model of prisoner's dilemma game and network structure to study the dynamic interaction in the real world. Based on the asynchronous update rule and Monte Carlo simulation, we find that, when players prefer to rewire their links to the richer, the cooperation density will increase. The reason of it has been analyzed.

physics.soc-ph↗

arXiv2008

Detection of subthreshold pulses in neurons with channel noise

Neurons are subject to various kinds of noise. In addition to synaptic noise, the stochastic opening and closing of ion channels represents an intrinsic source of noise that affects the signal processing properties of the neuron. In this paper, we studied the response of a stochastic Hodgkin-Huxley neuron to transient input subthreshold pulses. It was found that the average response time decreases but variance increases as the amplitude of channel noise increases. In the case of single pulse detection, we show that channel noise enables one neuron to detect the subthreshold signals and an optimal membrane area (or channel noise intensity) exists for a single neuron to achieve optimal performance. However, the detection ability of a single neuron is limited by large errors. Here, we test a simple neuronal network that can enhance the pulse detecting abilities of neurons and find dozens of neurons can perfectly detect subthreshold pulses. The phenomenon of intrinsic stochastic resonance is also found both at the level of single neurons and at the level of networks. At the network level, the detection ability of networks can be optimized for the number of neurons comprising the network.

q-bio.NC↗

arXiv2008

Effect of memory on the prisoner's dilemma game in a square lattice

We have studied the effect of memory on evolution of the prisoner's dilemma game using square lattice networks. Based on extensive simulations, we found that the density of cooperators was enhanced by an increasing memory effect for most parameters. However, we also observed that the density of cooperators decreased with an increased memory effect in the case of a large memory and moderate temptation. It is interesting to note that memory makes cooperators immune from temptation. The strength of protection reaches its maximal value only for the moderate memory effect.

physics.soc-ph↗

arXiv2008

Coexistence of hexatic and isotropic phases in two-dimensional Yukawa systems

We have performed Brownian dynamics simulations on melting of two-dimensional colloidal crystal in which particles interact with Yukawa potential. The pair correlation function and bond-orientational correlation function was calculated in the Yukawa system. An algebraic decay of the bond orientational correlation function was observed. By ruling out the coexistence region, only a unstable hexatic phase was found in the Yukawa systems. But our work shows that the melting of the Yukawa systems is a two-stage melting not consist with the KTHNY theory and the isotropic liquid and the hexatic phase coexistence region was found. Also we have studied point defects in two-dimensional Yukawa systems.

cond-mat.soft↗

arXiv2008

Emergence of synchronization induced by the interplay between two prisoner's dilemma games with volunteering in small-world networks

We studied synchronization between prisoner's dilemma games with voluntary participation in two Newman-Watts small-world networks. It was found that there are three kinds of synchronization: partial phase synchronization, total phase synchronization and complete synchronization, for varied coupling factors. Besides, two games can reach complete synchronization for the large enough coupling factor. We also discussed the effect of coupling factor on the amplitude of oscillation of $cooperator$ density.

physics.soc-ph↗

arXiv2007

Network growth approach to macroevolution

We propose a novel network growth model coupled with the competition interaction to simulate macroevolution. Our work shows that the competition plays an important role in macroevolution and it is more rational to describe the interaction between species by network structures. Our model presents a complete picture of the development of phyla and the splitting process. It is found that periodic mass extinction occurred in our networks without any extraterrestrial factors and the lifetime distribution of species is very close to fossil record. We also perturb networks with two scenarios of mass extinctions on different hierarchic levels in order to study their recovery.

q-bio.PE↗