113,472 research outputs found
Novelty and Collective Attention
The subject of collective attention is central to an information age where
millions of people are inundated with daily messages. It is thus of interest to
understand how attention to novel items propagates and eventually fades among
large populations. We have analyzed the dynamics of collective attention among
one million users of an interactive website -- \texttt{digg.com} -- devoted to
thousands of novel news stories. The observations can be described by a
dynamical model characterized by a single novelty factor. Our measurements
indicate that novelty within groups decays with a stretched-exponential law,
suggesting the existence of a natural time scale over which attention fades
Collective action for small-scale producers of agricultural biodiversity products:
"The role of well-functioning markets for development is now widely recognized, however the challenge remains to make these markets benefit the poor and the environment. Increasing attention is being given to the potential role markets can play for agrobiodiversity conservation through product diversification and increasing competitiveness in niche and novelty markets. Bioversity International has undertaken several studies that explore the use of market-based approaches to on-farm agrobiodiversity management and livelihood improvement. Case studies have been developed on a range of species, varieties and derived products, including underutilized species and commodities in several regions of the world. This paper explores how the theory of collective action can provide a more synthetic understanding of how market chains operate and how changes in the market chain and market institutions can permit a more equitable distribution of welfare benefits. The case studies illustrate the need for improved trust, a mutual understanding of each actor's involvement and the need for an agreed process of collective action that involves a high level of community participation to achieve an improved market chain organization benefiting the poor. The cases differ in their degree of collective action, the level of market organization and the ways in which handling, processing, and innovative marketing add value to the agrobiodiversity products. Comparative analysis of these cases identified a range of options and situations in which market development can support agrobiodiversity conservation and livelihoods. Bringing together these experiences will also help to identify the situations in which a collective approach can maximize the capturing of market benefits for smallholders. Trade-offs between income generation, livelihood security, and agrobiodiversity conservation should be further examined in order to find solutions that support sustainable development of poor communities that manage agricultural biodiversity." authors' abstractAgricultural biodiversity, Market chain, Market access, Livelihoods, Collective action, Small farmers, Biodiversity,
Attention and Visibility in an Information Rich World
As the rate of content production grows, we must make a staggering number of
daily decisions about what information is worth acting on. For any flourishing
online social media system, users can barely keep up with the new content
shared by friends. How does the user-interface design help or hinder users'
ability to find interesting content? We analyze the choices people make about
which information to propagate on the social media sites Twitter and Digg. We
observe regularities in behavior which can be attributed directly to cognitive
limitations of humans, resulting from the different visibility policies of each
site. We quantify how people divide their limited attention among competing
sources of information, and we show how the user-interface design can mediate
information spread.Comment: Appearing in 2nd International Workshop on Social Multimedia Research
2013, in conjunction with IEEE International Conference on Multimedia & Expo
(ICME 2013
Modeling the Rise in Internet-based Petitions
Contemporary collective action, much of which involves social media and other
Internet-based platforms, leaves a digital imprint which may be harvested to
better understand the dynamics of mobilization. Petition signing is an example
of collective action which has gained in popularity with rising use of social
media and provides such data for the whole population of petition signatories
for a given platform. This paper tracks the growth curves of all 20,000
petitions to the UK government over 18 months, analyzing the rate of growth and
outreach mechanism. Previous research has suggested the importance of the first
day to the ultimate success of a petition, but has not examined early growth
within that day, made possible here through hourly resolution in the data. The
analysis shows that the vast majority of petitions do not achieve any measure
of success; over 99 percent fail to get the 10,000 signatures required for an
official response and only 0.1 percent attain the 100,000 required for a
parliamentary debate. We analyze the data through a multiplicative process
model framework to explain the heterogeneous growth of signatures at the
population level. We define and measure an average outreach factor for
petitions and show that it decays very fast (reducing to 0.1% after 10 hours).
After 24 hours, a petition's fate is virtually set. The findings seem to
challenge conventional analyses of collective action from economics and
political science, where the production function has been assumed to follow an
S-shaped curve.Comment: Submitted to EPJ Data Scienc
Emergence: Key physical issues for deeper philosophical inquiries
A sketch of three senses of emergence and a suggestive view on the emergence
of time and the direction of time is presented. After trying to identify which
issues philosophers interested in emergent phenomena in physics view as
important I make several observations pertaining to the concepts, methodology
and mechanisms required to understand emergence and describe a platform for its
investigation. I then identify some key physical issues which I feel need be
better appreciated by the philosophers in this pursuit. I end with some
comments on one of these issues, that of coarse-graining and persistent
structures.Comment: 16 pages. Invited Talk at the Heinz von Foerster Centenary
International Conference on Self-Organization and Emergence: Emergent Quantum
Mechanics (EmerQuM11). Nov. 10-13, 2011, Vienna, Austria. Proceedings to
appear in J. Phys. (Conf. Series
Emergence: Key physical issues for deeper philosophical inquiries
A sketch of three senses of emergence and a suggestive view on the emergence
of time and the direction of time is presented. After trying to identify which
issues philosophers interested in emergent phenomena in physics view as
important I make several observations pertaining to the concepts, methodology
and mechanisms required to understand emergence and describe a platform for its
investigation. I then identify some key physical issues which I feel need be
better appreciated by the philosophers in this pursuit. I end with some
comments on one of these issues, that of coarse-graining and persistent
structures.Comment: 16 pages. Invited Talk at the Heinz von Foerster Centenary
International Conference on Self-Organization and Emergence: Emergent Quantum
Mechanics (EmerQuM11). Nov. 10-13, 2011, Vienna, Austria. Proceedings to
appear in J. Phys. (Conf. Series
Timescales of Massive Human Entrainment
The past two decades have seen an upsurge of interest in the collective
behaviors of complex systems composed of many agents entrained to each other
and to external events. In this paper, we extend concepts of entrainment to the
dynamics of human collective attention. We conducted a detailed investigation
of the unfolding of human entrainment - as expressed by the content and
patterns of hundreds of thousands of messages on Twitter - during the 2012 US
presidential debates. By time locking these data sources, we quantify the
impact of the unfolding debate on human attention. We show that collective
social behavior covaries second-by-second to the interactional dynamics of the
debates: A candidate speaking induces rapid increases in mentions of his name
on social media and decreases in mentions of the other candidate. Moreover,
interruptions by an interlocutor increase the attention received. We also
highlight a distinct time scale for the impact of salient moments in the
debate: Mentions in social media start within 5-10 seconds after the moment;
peak at approximately one minute; and slowly decay in a consistent fashion
across well-known events during the debates. Finally, we show that public
attention after an initial burst slowly decays through the course of the
debates. Thus we demonstrate that large-scale human entrainment may hold across
a number of distinct scales, in an exquisitely time-locked fashion. The methods
and results pave the way for careful study of the dynamics and mechanisms of
large-scale human entrainment.Comment: 20 pages, 7 figures, 6 tables, 4 supplementary figures. 2nd version
revised according to peer reviewers' comments: more detailed explanation of
the methods, and grounding of the hypothese
A Simple Generative Model of Collective Online Behaviour
Human activities increasingly take place in online environments, providing
novel opportunities for relating individual behaviours to population-level
outcomes. In this paper, we introduce a simple generative model for the
collective behaviour of millions of social networking site users who are
deciding between different software applications. Our model incorporates two
distinct components: one is associated with recent decisions of users, and the
other reflects the cumulative popularity of each application. Importantly,
although various combinations of the two mechanisms yield long-time behaviour
that is consistent with data, the only models that reproduce the observed
temporal dynamics are those that strongly emphasize the recent popularity of
applications over their cumulative popularity. This demonstrates---even when
using purely observational data without experimental design---that temporal
data-driven modelling can effectively distinguish between competing microscopic
mechanisms, allowing us to uncover new aspects of collective online behaviour.Comment: Updated, with new figures and Supplementary Informatio
- âŠ