Northeast Journal of Complex Systems最新文献

{"title":"Spectral Analysis of Multiscale Cultural Traits on Twitter","authors":"C. Squires, N. Kunapuli, Y. Bar-Yam, A. Morales","doi":"10.22191/nejcs/vol4/iss2/2","DOIUrl":"https://doi.org/10.22191/nejcs/vol4/iss2/2","url":null,"abstract":"Understanding and mapping the emergence and boundaries of cultural areas is a challenge for social sciences. In this paper, we present a method for analyzing the cultural composition of regions via Twitter hashtags. Cultures can be described as distinct combination of traits which we capture via principal component analysis (PCA). We investigate the top 8 PCA components of an area including France, Spain, and Portugal, in terms of the geographic distribution of their hashtag composition. We also discuss relationships between components and the insights those relationships can provide into the structure of a cultural space. Finally, we compare the spatial autocorrelation of PCA components in the Twitter data to similar components resulting from the Axelrod model. We conclude that properties of Twitter behavior can be framed in the discussion of cultural emergence and collective learning.","PeriodicalId":184569,"journal":{"name":"Northeast Journal of Complex Systems","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127847724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling Empirical Stock Market Behavior Using a Hybrid Agent-Based Dynamical Systems Model","authors":"Daniel A. Cline, Grant T. Aguinaldo, Christian Lemp","doi":"10.22191/nejcs/vol4/iss2/1","DOIUrl":"https://doi.org/10.22191/nejcs/vol4/iss2/1","url":null,"abstract":"We describe the development and calibration of a hybrid agent-based dynamical systems model of the stock market that is capable of reproducing empirical market behavior. The model consists of two types of trader agents, fundamentalists and noise traders, as well as an opinion dynamic for the latter (optimistic vs. pessimistic). The trader agents switch types stochastically over time based on simple behavioral rules. A system of ordinary differential equations is used to model the stock price as a function of the states of the trader agents. We show that the model can reproduce key stylized facts (e.g., volatility clustering and fat tails) while providing a behavioral interpretation of how the stock market itself can cause periods of high volatility and large price movements, even when the economic value of the stock grows at a constant rate.","PeriodicalId":184569,"journal":{"name":"Northeast Journal of Complex Systems","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126686416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toward Suicidal Ideation Detection with Lexical Network Features and Machine Learning","authors":"Ulya Bayram, William Lee, D. Santel, A. Minai, Peggy O. Clark, Tracy Glauser, J. Pestian","doi":"10.22191/nejcs/vol4/iss1/2","DOIUrl":"https://doi.org/10.22191/nejcs/vol4/iss1/2","url":null,"abstract":"In this study, we introduce a new network feature for detecting suicidal ideation from clinical texts and conduct various additional experiments to enrich the state of knowledge. We evaluate statistical features with and without stopwords, use lexical networks for feature extraction and classification, and compare the results with standard machine learning methods using a logistic classifier, a neural network, and a deep learning method. We utilize three text collections. The first two contain transcriptions of interviews conducted by experts with suicidal (n=161 patients that experienced severe ideation) and control subjects (n=153). The third collection consists of interviews conducted by experts with epilepsy patients, with a few of them admitting to experiencing suicidal ideation in the past (32 suicidal and 77 control). The selected methods detect suicidal ideation with an average area under the curve (AUC) score of 95% on the merged collection with high suicidal ideation, and the trained models generalize over the third collection with an average AUC score of 69%. Results reveal that lexical networks are promising for classification and feature extraction as successful as the deep learning model. We also observe that a logistic classifier’s performance was comparable with the deep learning method while promising explainability.","PeriodicalId":184569,"journal":{"name":"Northeast Journal of Complex Systems","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124268851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Representing and Analyzing the Dynamics of an Agent-Based Adaptive Social Network Model with Partial Integro-Differential Equations","authors":"Hiroki Sayama","doi":"10.22191/nejcs/vol4/iss1/3","DOIUrl":"https://doi.org/10.22191/nejcs/vol4/iss1/3","url":null,"abstract":"We formulated and analyzed a set of partial integro-differential equations that capture the dynamics of our adaptive network model of social fragmentation involving behavioral diversity of agents. Previous results showed that, if the agents’ cultural tolerance levels were diversified, the social network could remain connected while maintaining cultural diversity. Here we converted the original agent-based model into a continuous equation-based one so we can gain more theoretical insight into the model dynamics. We restricted the node states to 1-D continuous values and assumed the network size was very large. As a result, we represented the whole system as a set of partial integro-differential equations about two continuous functions: population density and connection density. These functions are defined over both the state and the cultural tolerance of nodes. We conducted numerical integration of the developed equations using a custom-made integrator implemented in Julia. The results obtained were consistent with the simulations of the original agent-based adaptive social network model we previously reported, confirming the robustness of the original finding. Specifically, when the variance of cultural tolerance d is large enough, the population with low d maintains the original clusters of cultures/opinions, while the one with high d tends to come to the center and connect culturally distant groups. Parameter dependence of the model behavior was also revealed through systematic numerical experiments.","PeriodicalId":184569,"journal":{"name":"Northeast Journal of Complex Systems","volume":"579 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131962697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bistability and Switching Behavior in Moving Animal Groups","authors":"D. Strömbom, Stephanie Nickerson, Catherine Futterman, A. Difazio, Cameron Costello, K. Tunstrøm","doi":"10.22191/nejcs/vol4/iss1/1","DOIUrl":"https://doi.org/10.22191/nejcs/vol4/iss1/1","url":null,"abstract":"Moving animal groups such as schools of fish and flocks of birds frequently switch between different group structures. Standard models of collective motion have been used successfully to explain how stable groups form via local interactions between individuals, but they are typically unable to produce groups that exhibit spontaneous switching. We are only aware of one model, constructed for barred flagtail fish that are known to rely on alignment and attraction to organize their collective motion, that has been shown to generate this type of behavior in 2D (or 3D). Interestingly, another species of fish, golden shiners, do exhibit switching but have been shown to use attraction and repulsion, not alignment, to coordinate themselves in schools. Suggesting that switching may be explained by attraction and repulsion alone, without an alignment interaction. Here we introduce a model based on attraction and repulsion only and show that groups exhibiting switching similar to that observed in experiments with golden shiners emerges. We also establish that switching occur in two boundary-free extensions of the model. Our work suggests that the bistability and switching behavior observed in golden shiners and other moving animal groups may be explained via attractive and repulsive interactions alone.","PeriodicalId":184569,"journal":{"name":"Northeast Journal of Complex Systems","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124311773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Waiting-Time Paradox in 1922","authors":"N. Masuda, Takayuki Hiraoka","doi":"10.22191/nejcs/vol2/iss1/1","DOIUrl":"https://doi.org/10.22191/nejcs/vol2/iss1/1","url":null,"abstract":"We present an English translation and discussion of an essay that a Japanese physicist, Torahiko Terada, wrote in 1922. In the essay, he described the waiting-time paradox, also called the bus paradox, which is a known mathematical phenomenon in queuing theory, stochastic processes, and modern temporal network analysis. He also observed and analyzed data on Tokyo City trams to verify the relevance of the waiting-time paradox to busy passengers in Tokyo at the time. This essay seems to be one of the earliest documentations of the waiting-time paradox in a sufficiently scientific manner.","PeriodicalId":184569,"journal":{"name":"Northeast Journal of Complex Systems","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114831572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rethinking Educational Reforms Through a Complex Dynamical Systems Approach: Preliminary Report from an Empirical Research","authors":"Eugenia Tsiouplis, D. Stamovlasis","doi":"10.22191/nejcs/vol1/iss1/3","DOIUrl":"https://doi.org/10.22191/nejcs/vol1/iss1/3","url":null,"abstract":"Literature on educational reforms is rich of cases where changes have been attempted, without however to attain success. Likewise the Greek education system had experienced a lot of reforms, most of which have failed to make the intended changes and they attenuated shortly after their implementation or they ceased at the stage of legislative planning. On the other hand, the traditional research have failed to develop a coherent theoretical perspective and provide satisfactory interpretations of the perpetually unsuccessful reforms. This paper is part of wider project which attempts to address the above issue following the Complex Dynamical Systems (CDS) perspective, that is, by fostering the CDS epistemological assumptions and applying nonlinear methodological approaches. This endeavor focuses on teachers' readiness for change and explores the dimensions of the resistance to change related to the values, attitudes, dysfunction beliefs and planed behaviors of teachers. Given that the project is still ongoing, here, only the outline of the research design and the strategy followed are discussed along with some preliminary findings. At a first stage, the investigation implemented focus-group settings to reveal clues of those dimensions. The recorded data were analyzed via orbital decomposition analysis (ODA), a method designed for categorical time series and discourse analysis. Some of the crucial dimensions of resistance-to-change were subsequently measured via a survey instrument and were used to predict teachers’ position with linear and nonlinear models. Statistical analysis showed that the cusp catastrophe model was superior to the linear alternatives and revealed discontinuities in teachers’ positions, while certain variables proved to be bifurcation factors. The implications of these findings are discussed, while methodological aspects of ODA and catastrophe theory modeling are briefly presented. The present work sets a framework for the application of complexity theory and nonlinear dynamics in organizational theory of educational change.","PeriodicalId":184569,"journal":{"name":"Northeast Journal of Complex Systems","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115405908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Being in Uncertainties: An Inquiry-based Model Leveraging Complexity in Teaching-Learning","authors":"D. Rosen","doi":"10.22191/nejcs/vol1/iss1/5","DOIUrl":"https://doi.org/10.22191/nejcs/vol1/iss1/5","url":null,"abstract":"Education is traditionally structured as a closed system, privileging result-driven methods that offer control and predictability. In recent decades this reductionist approach has been effectively challenged by interdisciplinary work in complex systems theory, revealing myriad levels of orderly disorder that make either-or, linear instruction an inadequate norm. Narrowing the broad implications of a complexity lens on education, this paper focuses on generative uncertainty in teaching-learning, a paradoxical state of epistemological and creative growth described by English poet John Keats as \"the negative capability of being in uncertainties, mysteries, doubts.\" Opportunities to advance this potentiating capacity are especially abundant in constructivist curricula, for example the Methods of Inquiry (MoI) program discussed herein. MoI's open, complexitybased approach foregrounds uncertainty-tolerance and other interactive dispositions, providing a fluid structure for the emergent, often turbulent nature of meaning production. Such dynamic attitudes and strategies are seen as essential for any classroom practice that seeks to transform as well as inform, to guide and also empower.","PeriodicalId":184569,"journal":{"name":"Northeast Journal of Complex Systems","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124429501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Academic Skill Learning and the Problem of Complexity I: Creational Purposeful Integrated Capability at Skill (CPICS)","authors":"M. Gardiner","doi":"10.22191/nejcs/vol1/iss1/7","DOIUrl":"https://doi.org/10.22191/nejcs/vol1/iss1/7","url":null,"abstract":"Physical and mental skills are intended to achieve success at acting purposefully. As capability at any skill increases, the need to adjust details of application to complexity of context and goals will increase as well. It will become more and more important to prepare mentally for what I now term Creational Purposeful Integrated Capability at Skill (CPICS). This paper develops what I mean by CPICS. Theory concerning Complex Dynamical Systems (CDS) such as the brain and other evidence points to the likelihood that the mental operations by which our brain produces any kind of skillful behavior cannot remain constant, but rather must develop through stages for skill to progress most profitably. Using early stages of math learning as an example, I propose that what can hold back some students at development of a skill is that even if presented with all the information need for progress, some students have not yet discovered how to make the most useful mental restructuring that is also needed. This paper proposes and discusses as an example details of what may be especially useful restructuring for early stages of math skill learning. This example is then taken as helping to identify the more general type of restructuring that is especially useful for addressing complexity of application that produces CPICS at every stage of skill improvement. 1. The Role of Mental Restructuring in Skill Improvement The discussion that follows builds upon earlier work (Gardiner et al, 1996; Gardiner, 2000, 2003, 2008, 2019). By skillful “engagement” (Gardiner, 2008) I refer to the specific brain actions that produce skillful physical behavior (such as at walking) or skillful mental behavior (such as at solving a math problem). William James pointed out more than a century ago (James, 1890, 1896) that to live in a complex world we must simplify our interactions with it. But, to paraphrase Einstein’s famous saying, we must think as simply as possible, but not more simply than possible. 2. Insight from Bicycle Riding, Theory of Complex Dynamical Systems (CDS) and Related Evidence 1 Gardiner: Academic Skill Learning and the Problem of Complexity: I Published by The Open Repository @ Binghamton (The ORB), 2019 Physical skills such as at learning to ride a bicycle illustrate what this paper now discusses in relation to academic learning as well. Once learners understand the bicycle and what they must accomplish, further progress must depend on their somehow developing better ways to use their brains to produce bike riding skillfully. Suggestions and help at training by parents, and training wheels can help, but ultimately qualitative improvement in engagement must take place out of direct control by the learners and outside of their conscious awareness. Capability at riding suddenly jumps from not possible to possible. Once possible the capability may continue to develop. But not until this first step. Development of academic skills such as at math, I now argue, also depe","PeriodicalId":184569,"journal":{"name":"Northeast Journal of Complex Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129018535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Patterning Approach to Complexity Thinking and Understanding for Students: A Case Study","authors":"Shae L. Brown","doi":"10.22191/nejcs/vol1/iss1/6","DOIUrl":"https://doi.org/10.22191/nejcs/vol1/iss1/6","url":null,"abstract":"Complexity thinking and understanding are vital skills for young people in these times of uncertainty and change. Such skills contribute to resilience and capacities for adaptivity and innovation. Within my teaching practice I have found students to be aware of complex dynamics, uncertainty and change, both in their lives and in the world. However, the current curriculum lacks language and process to conceptualise, articulate and develop complexity understanding. To address this problem, I developed and introduced a patterns-based design and process to a cohort of Australian secondary students. Comprising flowform patterning together with ecological metaphors, the design forms a conceptual language and practical process for thinking about, understanding and engaging with complex phenomena and change. Together these capacities are described here as complexity competence. Implemented initially to engage with time as a complex phenomenon, the design is described as the Patterns of Humantime (PHT), and the process of implementation as Complexity Patterning . Implementation during the development phase demonstrated the design’s capacity as a way to understand time as a complex phenomenon, as well as facilitating a relational and identity development approach to learning. In more recent research workshops with American undergraduate Liberal Studies students, the PHT design showed to be effective for understanding complexity and indicated the design’s capacity as a patterning process for engaging in collaborative projects in complex situations of diversity, change and uncertainty. Avenues to develop curriculum and evaluation materials, as well as professional development workshops, are being explored.","PeriodicalId":184569,"journal":{"name":"Northeast Journal of Complex Systems","volume":"18 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120889209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}