31 citations · 170 across the 19 of their papers we have counts for
20 papers
Disentangling epidemics and percolation
Takayuki Hiraoka, Jari Saramäki
Non-recurrent epidemics on complex networks, such as the paradigmatic susceptible-infected-recovered (SIR) model, are often studied by mapping the model to bond percolation. Howeve…
Coevolution of epidemic dynamics and network topology driven by disease fatality and waning immunity
ThankGod I. S. Ikpe, Takayuki Hiraoka, Naoya Fujiwara
Epidemics on complex networks have been shown to exhibit dynamics that are strongly influenced by the topology of the network. However, it remains unclear how the topology of the n…
Message passing and cyclicity transition
Takayuki Hiraoka
Message passing, also known as belief propagation, is a versatile framework for analyzing models defined on graphs. Its most prototypical application is percolation; yet, the inter…
Epidemic reproduction numbers in spatial networks
Zahra Ghadiri, Jari Saramäki, Takayuki Hiraoka
The basic and effective reproduction numbers are widely used metrics for characterizing the dynamics of infectious disease epidemics. However, the interpretation of these numbers i…
Hierarchical organization of bursty trains in event sequences
Takayuki Hiraoka, Hang-Hyun Jo
Temporal sequences of discrete events that describe natural and social processes are often driven by non-Poisson dynamics. In addition to a heavy-tailed interevent time distributio…
Block-corrected Modularity for Community Detection
Hasti Narimanzadeh, Takayuki Hiraoka, Mikko Kivelä
Unknown node attributes in complex networks may introduce community structures that are important to distinguish from those driven by known attributes. We propose a block-corrected…
Geospatial analysis of toponyms in geotagged social media posts
Takayuki Hiraoka, Takashi Kirimura, Naoya Fujiwara
Place names, or toponyms, play an integral role in human representation and communication of geographic space. In particular, how people relate each toponym with particular locatio…
Strength and weakness of disease-induced herd immunity in networks
Takayuki Hiraoka, Zahra Ghadiri, Abbas K. Rizi +2
When a fraction of a population becomes immune to an infectious disease, the population-wide infection risk decreases nonlinearly due to collective protection, known as herd immuni…
Herd Immunity and Epidemic Size in Networks with Vaccination Homophily
Takayuki Hiraoka, Abbas K. Rizi, Mikko Kivelä +1
We study how the herd immunity threshold and the expected epidemic size depend on homophily with respect to vaccine adoption. We find that the presence of homophily considerably in…
Adaptive and optimized COVID-19 vaccination strategies across geographical regions and age groups
Jeta Molla, Alejandro Ponce de León Chávez, Takayuki Hiraoka +3
We evaluate the efficiency of various heuristic strategies for allocating vaccines against COVID-19 and compare them to strategies found using optimal control theory. Our approach…
Individual-driven versus interaction-driven burstiness in human dynamics: The case of Wikipedia edit history
Jeehye Choi, Takayuki Hiraoka, Hang-Hyun Jo
The origin of non-Poissonian or bursty temporal patterns observed in various datasets for human social dynamics has been extensively studied, yet its understanding still remains in…
Waiting-time paradox in 1922
Naoki Masuda, Takayuki Hiraoka
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 ca…
Modeling temporal networks with bursty activity patterns of nodes and links
Takayuki Hiraoka, Naoki Masuda, Aming Li +1
The concept of temporal networks provides a framework to understand how the interaction between system components changes over time. In empirical communication data, we often detec…
Burst-tree decomposition of time series reveals the structure of temporal correlations
Hang-Hyun Jo, Takayuki Hiraoka, Mikko Kivelä
Comprehensive characterization of non-Poissonian, bursty temporal patterns observed in various natural and social processes is crucial to understand the underlying mechanisms behin…
Bursty time series analysis for temporal networks
Hang-Hyun Jo, Takayuki Hiraoka
Characterizing bursty temporal interaction patterns of temporal networks is crucial to investigate the evolution of temporal networks as well as various collective dynamics taking…
Copula-based algorithm for generating bursty time series
Hang-Hyun Jo, Byoung-Hwa Lee, Takayuki Hiraoka +1
Dynamical processes in various natural and social phenomena have been described by a series of events or event sequences showing non-Poissonian, bursty temporal patterns. Temporal…
Correlated bursts in temporal networks slow down spreading
Takayuki Hiraoka, Hang-Hyun Jo
Spreading dynamics has been considered to take place in temporal networks, where temporal interaction patterns between nodes show non-Poissonian bursty nature. The effects of inhom…
Limits of memory coefficient in measuring correlated bursts
Hang-Hyun Jo, Takayuki Hiraoka
Temporal inhomogeneities in event sequences of natural and social phenomena have been characterized in terms of interevent times and correlations between interevent times. The inho…
The effect of laziness in chasers in group chase and escape model
Makoto Masuko, Takayuki Hiraoka, Nobuyasu Ito +1
The effect of laziness in the group chase and escape problem is studied using a simple model. The laziness is introduced as random walks in two ways: uniformly and in a "division o…
Order-disorder transition in repulsive self-propelled particle systems
Takayuki Hiraoka, Takashi Shimada, Nobuyasu Ito
We study the collective dynamics of repulsive self-propelled particles. The particles are governed by coupled equations of motion that include polar self-propulsion, damping of vel…