Bursty Human Dynamics

This book provides a comprehensive overview on emergent bursty patterns in the dynamics of human behaviour. It presents common and alternative understanding of the investigated phenomena, and points out open questions worthy of further investigations. The book is structured as follows. In the introduction the authors discuss the motivation of the field, describe bursty phenomena in case of human behaviour, and relate it to other disciplines. The second chapter addresses the measures commonly used to characterise heterogeneous signals, bursty human dynamics, temporal paths, and correlated behaviour. These definitions are first introduced to set the basis for the discussion of the third chapter about the observations of bursty human patterns in the dynamics of individuals, dyadic interactions, and collective behaviour. The subsequent fourth chapter discusses the models of bursty human dynamics. Various mechanisms have been proposed about the source of the heterogeneities in human dynamics, which leads to the introduction of conceptually different modelling approaches. The authors address all of these perspectives objectively, highlight their strengths and shortcomings, and mention possible extensions to them. The fifth chapter addresses the effect of individual heterogeneous behaviour on collective dynamics. This question in particular has been investigated in various systems including spreading phenomena, random walks, and opinion formation dynamics. Here the main issues are whether burstiness speeds up or slows down the co-evolving processes, and how burstiness modifies time-dependent paths in the system that determine the spreading patterns of any kind of information or influence. Finally in the sixth chapter the authors end the review with a discussion and future perspectives. It is an ideal book for researchers and students who wish to enter the field of bursty human dynamics or want to expand their knowledge on such phenomena. Preface 7 Acknowledgements 8 Contents 9 Acronyms 11 1 Introduction 13 1.1 Bursty Human Dynamics 16 1.2 About This Monograph 18 2 Measures and Characterisations 19 2.1 Point Processes as Time Series with Irregular Timings 20 2.1.1 The Poisson Process 21 2.1.2 Characterisation of Temporal Heterogeneities 21 2.2 Inter-event Time, Residual Time, and Waiting Time 30 2.3 Collective Bursty Phenomena 31 2.3.1 Bursty Patterns in Egocentric Networks 32 2.3.2 Bursty Temporal Motifs 35 2.3.3 System Level Characterisation 37 2.4 Cyclic Patterns in Human Dynamics 37 2.4.1 Remark on Non-stationarity 40 3 Empirical Findings in Human Bursty Dynamics 42 3.1 Individual Activities 42 3.2 Interaction-Driven Collective Activities 43 3.2.1 Face-to-face Interactions 46 3.2.2 Mobile Phone-Based Interactions 47 3.2.3 Communication by Posted Letters and Emails 50 3.2.4 Web-Based Activities and Social Interactions 51 3.3 Other Bursty Patterns 53 3.3.1 Financial Activities 54 3.3.2 Human Mobility 55 3.3.3 Animal Behaviours 57 4 Models and Mechanisms of Bursty Behaviour 58 4.1 Models of Individual Activity 58 4.1.1 Queuing Models of Bursty Phenomena 58 4.1.2 Memory Driven Models of Bursty Phenomena 64 4.1.3 Poisson Models of Bursty Phenomena 68 4.1.4 Other Type of Models 73 4.2 Models of Link Activity 75 4.2.1 Interacting Priority Queues 75 4.2.2 Models with Combined Mechanisms 76 4.3 Network Models of Bursty Agents 77 4.3.1 Zero-Crossing Random Walk Model 77 4.3.2 Reinforcement Models of Group Formation 78 4.3.3 Evolving Networks with Interacting Priority Queues 78 4.3.4 Dynamic Networks with Memory 79 4.3.5 Activity Driven Network Models with Bursty Nodes 80 5 Dynamical Processes on Bursty Systems 83 5.1 Bursty Characteristics Controlling Dynamical Processes 84 5.1.1 Inter-event Time and Residual Time Distributions 84 5.1.2 Triggered Event Correlations 93 5.1.3 Effects of Link Burstiness 94 5.1.4 Other Bursty Characters 95 5.1.5 Dominant Characters 96 5.2 Dynamical Processes on Bursty Temporal Networks 98 5.2.1 Epidemic Spreading 98 5.2.2 Random Walks 101 5.2.3 Threshold Models 104 5.2.4 Evolutionary Games 105 5.2.5 Dynamical Process Induced Bursty Behaviour 106 6 Discussion 108 6.1 Future Directions and Methodological Approaches 111 References 114 Index 127 Front Matter ....Pages i-xiv Introduction (Márton Karsai, Hang-Hyun Jo, Kimmo Kaski)....Pages 1-6 Measures and Characterisations (Márton Karsai, Hang-Hyun Jo, Kimmo Kaski)....Pages 7-29 Empirical Findings in Human Bursty Dynamics (Márton Karsai, Hang-Hyun Jo, Kimmo Kaski)....Pages 31-46 Models and Mechanisms of Bursty Behaviour (Márton Karsai, Hang-Hyun Jo, Kimmo Kaski)....Pages 47-71 Dynamical Processes on Bursty Systems (Márton Karsai, Hang-Hyun Jo, Kimmo Kaski)....Pages 73-97 Discussion (Márton Karsai, Hang-Hyun Jo, Kimmo Kaski)....Pages 99-104 Back Matter ....Pages 105-121