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1.
The naming game model characterizes the main evolutionary features of languages or more generally of communication systems. Very recently, the combination of complex networks and the naming game has received much attention and the influences of various topological properties on the corresponding dynamical behavior have been widely studied. In this paper, we investigate the naming game on small-world geographical networks. The small-world geographical networks are constructed by randomly adding links to two-dimensional regular lattices, and it is found that the convergence time is a nonmonotonic function of the geographical distance of randomly added shortcuts. This phenomenon indicates that, although a long geographical distance of the added shortcuts favors consensus achievement, too long a geographical distance of the added shortcuts inhibits the convergence process, making it even slower than the moderates.  相似文献   

2.
Human history leaves fingerprints in human languages. Little is known about language evolution and its study is of great importance. Here we construct a simple stochastic model and compare its results to statistical data of real languages. The model is based on the recent finding that language changes occur independently of the population size. We find agreement with the data additionally assuming that languages may be distinguished by having at least one among a finite, small number of different features. This finite set is also used in order to define the distance between two languages, similarly to linguistics tradition since Swadesh.  相似文献   

3.
The idea of measuring distance between languages seems to have its roots in the work of the French explorer Dumont D’Urville (1832) [13]. He collected comparative word lists for various languages during his voyages aboard the Astrolabe from 1826 to 1829 and, in his work concerning the geographical division of the Pacific, he proposed a method for measuring the degree of relation among languages. The method used by modern glottochronology, developed by Morris Swadesh in the 1950s, measures distances from the percentage of shared cognates, which are words with a common historical origin. Recently, we proposed a new automated method which uses the normalized Levenshtein distances among words with the same meaning and averages on the words contained in a list. Recently another group of scholars, Bakker et al. (2009) [8] and Holman et al. (2008) [9], proposed a refined version of our definition including a second normalization. In this paper we compare the information content of our definition with the refined version in order to decide which of the two can be applied with greater success to resolve relationships among languages.  相似文献   

4.
《Physica A》2005,345(1-2):227-244
Power laws in socioeconomic systems are generally explained as being generated by multiplicative growth of aggregate objects. In this paper we formulate a model of geographic activity distribution with spatial correlations on the level of land lots where multiplicative growth is assumed to be dominant but not exclusive. The purpose is to retain the explanatory power of earlier models due to Simon, Gibrat and others while attaining some additional properties that are attractive for both empirical and modelling purposes. In this sense, the model presented here is a combination of the two factors that have been identified as central to urban evolution but rarely appear unified in the same model: transportation costs and multiplicative growth. The model is an elaboration of a previously reported complex network model of geographical land value evolution. We reproduce statistical properties of an empirical geographical distribution of land values on multiple hierarchical levels: land value per unit area, cluster areas, aggregated land value per cluster and cluster area/perimeter ratios. It is found that transportation effects are not strong enough to disturb the power law distribution of land values per unit area but strong enough to sort nodes to generate a new set of power laws on a higher level of aggregation. The main hypothesis is that all these relations can be understood as consequences of an underlying growing scale-free network of geographic economic interdependencies.  相似文献   

5.
A factor-analytic model, PARAFAC, has been shown to yield highly significant and interpretable results when applied to the analysis of tongue shapes in particular languages. However, the forms of the solutions differ from language to language. A conceptual model that provides an account for cross-language variability in terms of coordinative structures that may vary in a language-specific manner is developed. This model rationalizes both the success of the PARAFAC procedure within languages and the poor cross-language replicability of PARAFAC solutions. We consider methods for quantitatively comparing the results of PARAFAC analyses of data from different languages using data from Icelandic and English as a test case. A cross-language factor solution that accounts for 90% of the variance in tongue position measurements is presented and interpreted in terms of the conceptual model.  相似文献   

6.
由于红外光谱数据采集受仪器状态和实验环境的制约,影响对样品的正确识别。基于傅里叶变换红外光谱(FTIR)技术,用多种方法对两面针的红外光谱数据进行校正后,利用SIMCA法建立鉴别模型;分别对广西区内四个产地的两面针进行鉴别,通过比较分析以获得最适合建立两面针产地鉴别模型的光谱数据校正方法。结果显示,经多元散射校正和标准正态变换后,它们的PCA数据分布,以及产地分类模型之间的距离,都表明这两种校正方法在消除环境和人为因素的干扰的同时,能够很好的分离各个产地的样本,在对实际的样本识别中,其识别率和拒绝率均达到或接近100%。可见,多元散射校正和标准正态变换,均是两面针产地模型鉴别研究的理想校正方法。  相似文献   

7.
罗植  杨冠琼  狄增如 《物理学报》2012,61(19):190509-190509
舆论形成是个体因素与外部影响共同作用的结果. 个体因素包括个体理性的认知与非理性的情绪因素, 外部影响则包括文化、认知以及行为模式的作用和社会网络上个体之间的影响, 而文化、认知等背景因素往往与空间地域相关联. 本文通过构建一个同时具有空间位置特征与小世界特征的无标度网络以及网络上的Ising模型, 全面考察了空间与网络共同作用对舆论形成的影响, 研究了舆论形成中的相变行为, 重点分析了与区域文化或认知背景以及与整体社会情绪等相关的参数在舆论形成过程中的作用. 计算机数值模拟结果表明, 区域间的认知背景差异足够大时, 会导致公共舆论形成明显的区域性特征, 此时, 空间因素和社会网络具有同样的影响强度时, 会有利于全局一致舆论的形成. 同时, 非理性因素引发的社会情绪可以通过提高个体影响力及降低背景差异使得一致性公共舆论快速形成.  相似文献   

8.
This paper formulates a random-growth urban model with a notion of geographical fitness. Using techniques of complex-network theory, we study our system as a type of preferential-attachment model with fitness, and we analyze its macro behavior to clarify the properties of the city-size distributions it predicts. First, restricting the geographical fitness to take positive values and using a continuum approach, we show that the city-size distributions predicted by our model asymptotically approach Pareto distributions with coefficients greater than unity. Then, allowing the geographical fitness to take negative values, we perform local coefficient analysis to show that the predicted city-size distributions can deviate from Pareto distributions, as is often observed in actual city-size distributions. As a result, the model we propose can generate a generic class of city-size distributions, including but not limited to Pareto distributions. For applications to city-population projections, our simple model requires randomness only when new cities are created, not during their subsequent growth. This property leads to smooth trajectories of city population growth, in contrast to other models using Gibrat’s law. In addition, a discrete form of our dynamical equations can be used to estimate past city populations based on present-day data; this fact allows quantitative assessment of the performance of our model. Further study is needed to determine appropriate formulas for the geographical fitness.  相似文献   

9.
Entropy estimation faces numerous challenges when applied to various real-world problems. Our interest is in divergence and entropy estimation algorithms which are capable of rapid estimation for natural sequence data such as human and synthetic languages. This typically requires a large amount of data; however, we propose a new approach which is based on a new rank-based analytic Zipf–Mandelbrot–Li probabilistic model. Unlike previous approaches, which do not consider the nature of the probability distribution in relation to language; here, we introduce a novel analytic Zipfian model which includes linguistic constraints. This provides more accurate distributions for natural sequences such as natural or synthetic emergent languages. Results are given which indicates the performance of the proposed ZML model. We derive an entropy estimation method which incorporates the linguistic constraint-based Zipf–Mandelbrot–Li into a new non-equiprobable coincidence counting algorithm which is shown to be effective for tasks such as entropy rate estimation with limited data.  相似文献   

10.
太平猴魁茶因其特有的“喉韵”深受广大消费者喜爱,不同产地太平猴魁茶市场价格相差较大,如何实现产地精准鉴别是目前促进绿茶产业发展的关键因素。依赖于人工经验的感官评审方法主观性强、稳定性差,无法应用于实际生产检测过程。作为目前主要的检测分析方法,化学分析方法周期长、检测成本高,而且目前没有用于茶叶产地鉴别的统一标准。近红外光谱(NIR)作为一种无损检测分析方法,具有快速、非破坏性、无污染等特点,但是不同产地太平猴魁茶主要内含成分及其含量基本相同,不同产地样本光谱特征峰分布相似,导致常规分析方法无法有效选择特征变量。卷积神经网络(CNN)作为经典深度学习网络模型之一,具有强特征提取和模型表达能力。采用太平猴魁茶产地光谱特征分析,利用一维卷积神经网络模型(1-D CNN)提取太平猴魁茶NIR特征,提出一种基于1-D CNN和NIR的太平猴魁茶产地鉴别分析方法。试验以6个不同产地共120个样本为研究对象,分析10 000~4 000 cm-1范围内的光谱信息;将样本随机划分为训练集(84,占70%)和测试集(36,占30%),分别讨论不同间隔采样、网络结构、卷积核大小及激活函数对产地鉴别结果的影响,并引入Dropout方法对比分析模型过拟合现象;最终建立一个具有9层结构的1-D CNN模型。蒙特卡罗试验结果表明,相比于基于原始光谱数据(40.57%,7.06)和PCA方法(31.93%,6.96)的太平猴魁茶产地预测模型准确率和标准差,基于1-D CNN的太平猴魁茶产地鉴别模型预测精度和稳定性更高,其测试集预测准确率平均值和标准差分别为97.73%和3.47。因此,1-D CNN可有效提取太平猴魁茶不同产地NIR特征,提高太平猴魁茶产地鉴别精度,为太平猴魁茶精准产地鉴别及溯源分析提供参考。  相似文献   

11.
We review some recent endeavors and add some new results to characterize and understand underlying mechanisms in Wikipedia (WP), the paradigmatic example of collaborative value production. We analyzed the statistics of editorial activity in different languages and observed typical circadian and weekly patterns, which enabled us to estimate the geographical origins of contributions to WPs in languages spoken in several time zones. Using a recently introduced measure we showed that the editorial activities have intrinsic dependencies in the burstiness of events. A comparison of the English and Simple English WPs revealed important aspects of language complexity and showed how peer cooperation solved the task of enhancing readability. One of our focus issues was characterizing the conflicts or edit wars in WPs, which helped us to automatically filter out controversial pages. When studying the temporal evolution of the controversiality of such pages we identified typical patterns and classified conflicts accordingly. Our quantitative analysis provides the basis of modeling conflicts and their resolution in collaborative environments and contribute to the understanding of this issue, which becomes increasingly important with the development of information communication technology.  相似文献   

12.
《Physica A》2006,361(1):355-360
In this work we study the dynamics of language competition. In Abrams and Strogatz [Modeling the dynamics of language death, Nature 424 (2003) 900], the extinction of one of the competing languages is predicted, although in some case the coexistence occurs. The preservation of both languages was explained by Patriarca and Leppanen [Modeling language competition, Physica A 338 (2004) 296] by introducing the existence of two disjoint zones where each language is predominant. However, their results cannot explain the survivance of both languages in only one zone of competition. In this work we discuss their results and propose a new alternative model of Lotka–Volterra type in order to explain the coexistence of two languages.  相似文献   

13.
This study examined whether speech-on-speech masking is sensitive to variation in the degree of similarity between the target and the masker speech. Three experiments investigated whether speech-in-speech recognition varies across different background speech languages (English vs Dutch) for both English and Dutch targets, as well as across variation in the semantic content of the background speech (meaningful vs semantically anomalous sentences), and across variation in listener status vis-a?-vis the target and masker languages (native, non-native, or unfamiliar). The results showed that the more similar the target speech is to the masker speech (e.g., same vs different language, same vs different levels of semantic content), the greater the interference on speech recognition accuracy. Moreover, the listener's knowledge of the target and the background language modulate the size of the release from masking. These factors had an especially strong effect on masking effectiveness in highly unfavorable listening conditions. Overall this research provided evidence that that the degree of target-masker similarity plays a significant role in speech-in-speech recognition. The results also give insight into how listeners assign their resources differently depending on whether they are listening to their first or second language.  相似文献   

14.
Parapatric speciation is studied using an individual-based model with sexual reproduction. We combine the theory of mutation accumulation for biological ageing with an environmental selection pressure that varies according to the individuals geographical positions and phenotypic traits. Fluctuations and genetic diversity of large populations are crucial ingredients to model the features of evolutionary branching and are intrinsic properties of the model. Its implementation on a spatial lattice gives interesting insights into the population dynamics of speciation on a geographical landscape and the disruptive selection that leads to the divergence of phenotypes. Our results suggest that assortative mating is not an obligatory ingredient to obtain speciation in large populations at low gene flow.  相似文献   

15.
We study geographical effects on the spread of diseases in lattice-embedded scale-free networks. The geographical structure is represented by the connecting probability of two nodes that is related to the Euclidean distance between them in the lattice. By studying the standard susceptible-infected model, we found that the geographical structure has great influences on the temporal behavior of epidemic outbreaks and the propagation in the underlying network: the more geographically constrained the network is, the more smoothly the epidemic spreads, which is different from the clearly hierarchical dynamics that the infection pervades the networks in a progressive cascade across smaller-degree classes in Barabási–Albert scale-free networks.  相似文献   

16.
In this paper, we analyze statistical properties of a communication network constructed from the records of a mobile phone company. The network consists of 2.5 million customers that have placed 810 million communications (phone calls and text messages) over a period of 6 months and for whom we have geographical home localization information. It is shown that the degree distribution in this network has a power-law degree distribution k−5 and that the probability that two customers are connected by a link follows a gravity model, i.e. decreases as d−2, where d is the distance between the customers. We also consider the geographical extension of communication triangles and we show that communication triangles are not only composed of geographically adjacent nodes but that they may extend over large distances. This last property is not captured by the existing models of geographical networks and in a last section we propose a new model that reproduces the observed property. Our model, which is based on the migration and on the local adaptation of agents, is then studied analytically and the resulting predictions are confirmed by computer simulations.  相似文献   

17.
We extend the Abrams–Strogatz model for competition between two languages (Abrams and Strogatz in Nature 424:900, 2003) to the case of n (≥2) competing states (i.e., languages). Although the Abrams–Strogatz model for n=2 can be interpreted as modeling either majority preference or minority aversion, the two mechanisms are distinct when n≥3. We find that the condition for the coexistence of different states is independent of n under the pure majority preference, whereas it depends on n under the pure minority aversion. We also show that the stable coexistence equilibrium and stable monopoly equilibria can be multistable under the minority aversion and not under the majority preference. Furthermore, we obtain the phase diagram of the model when the effects of the majority preference and minority aversion are mixed, under the condition that different states have the same attractiveness. We show that the multistability is a generic property of the model facilitated by large n.  相似文献   

18.
复杂地理环境是电波传播不可避免的传播环境,不仅不规则地形会对电波传播产生影响,不同的地表媒质对电波传播也会产生不同的影响。为了使得电波传播特性的预测结果更加地准确有效,通过图像分割算法实现地表环境的简单分类,同时对不同的媒质赋予不同的电磁参数,并结合数字高程模型(DEM)数据,实现了既具有地形起伏信息又具有地表电磁环境参数的复杂地理环境建模。在此基础上,对地表电磁环境信息做了网格剖分处理,利用抛物方程(PE)模型对复杂地理环境下的电波传播特性进行了预测。  相似文献   

19.
潘登  郑应平 《物理学报》2015,64(7):78902-078902
复杂地理环境下车辆运行线路具有空间三维特征, 它对车辆行为的约束是显然的, 非一维空间和二维空间所能描述. 将复杂地理环境下车辆运行线路抽象为空间曲线, 引入微分几何理论, 利用弧长、曲率和挠率等几何不变量参数建立沿空间曲线运动的Serret-Frenet活动标架; 然后, 对空间曲线上任意一点处Serret-Frenet标架具有时变属性的动态行为进行数学描述, 进而建立路径约束条件下车辆行为的时空演化模型, 并在数学上严格证明了所建时空演化模型适用于车辆(Serret-Frenet标架)直线运行和做匀速圆周运动的特殊情形. 为后续复杂地理环境中交通线路上的车辆跟驰、变道等微观行为和交通流宏观行为研究, 奠定了理论基础.  相似文献   

20.
Dependency distance, measured by the linear distance between two syntactically related words in a sentence, is generally held as an important index of memory burden and an indicator of syntactic difficulty. Since this constraint of memory is common for all human beings, there may well be a universal preference for dependency distance minimization (DDM) for the sake of reducing memory burden. This human-driven language universal is supported by big data analyses of various corpora that consistently report shorter overall dependency distance in natural languages than in artificial random languages and long-tailed distributions featuring a majority of short dependencies and a minority of long ones. Human languages, as complex systems, seem to have evolved to come up with diverse syntactic patterns under the universal pressure for dependency distance minimization. However, there always exist a small number of long-distance dependencies in natural languages, which may reflect some other biological or functional constraints. Language system may adapt itself to these sporadic long-distance dependencies. It is these universal constraints that have shaped such a rich diversity of syntactic patterns in human languages.  相似文献   

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