Author Archives: luai

NERDS at ICWSM’24

This week, Arianna and Anders are representing NERDS at ICWSM in Buffalo, NY, with two freshly-published papers.

  1. Narratives of Collective Action in YouTube’s Discourse on Veganism, by A. Pera and L.M. Aiello. ICWSM’24.

    We studied vegan narratives on YouTube through the lens of a theoretical framework of moral narratitves. We studied how different narratives elicit different types of responses from video commenters, and found that videos advocating social activism are the most effective at stirring reactions marked by heightened linguistic markers that relate to collective action.
  2. The Persuasive Power of Large Language Models by A.G. Møller and L.M. Aiello. ICWSM’24.

    Can artificial agents interact with each other to reproduce human-like persuasive dialogue? And do the arguments they generate sound persuasive to humans? We used Llama2 to test different persuasion strategies, and asked humans to rate them. We found that arguments that included factual knowledge, markers of trust, expressions of support, and conveyed status were deemed most effective according to both humans and agents.

NERDS at Como Summer School and WebSci’24

Arianna and Anders participated to the first editions of the Computational Social Science Summer School in Como, presenting their work on the COCOONS project. Arianna, Daniele, and external collaborator Maddalena Torricelli also attended the WebSci conference in Stuttgard, presenting an analysis of climate action communication on TikTok [paper], the use of hypergraphs to model opinion dynamics in large-scale social media [poster], and the role of interfaces in shaping human creativity during the interaction with generative AI tools [paper].

Welcome Anders to NERDS!

Anders Giovanni Møller graduation at ITU

NERDS welcomes a new member: Anders Giovanni Møller. Starting today, Anders will be a PhD student working with Luca Aiello on the COCOONS project at the intersection between NLP and complex systems. Anders can boast a long tenure at ITU, and last week he got his Master’s degree in Data Science. He was selected for a keynote address to the whole 2023 cohort of ITU MSc graduates during the graduation ceremony — a very moving and inspiring speech! Welcome, Anders!

Welcome Iraklis to NERDS!

Iraklis Moutidis joins NERDS today as a postdoctoral researcher. He will work with Luca Aiello on the COCOONS project. Iraklis got his PhD in Computer Science from the University of Exeter (UK) and he works at the intersection of Machine Learning and Social Network Analysis. Welcome, Iraklis!

Arianna Pera has joined NERDS

We are thrilled to welcome Arianna Pera to NERDS!

Arianna will be a PhD student for 3 years, working with Luca Aiello on the Carlsbergfondet project COCOONS on fostering collective cooperation in online social media to tackle societal dilemmas. Arianna recently got her MSc in Data Science from Università degli Studi di Milano-Bicocca. She will work at the intersection of Network Science and Natural Language Processing. Welcome, Arianna!

 

 

New NERDS paper: Multidimensional tie strength and economic development

Multidimensional tie strength and economic development, by L.M. Aiello, S. Joglekar, and D. Quercia, published in Scientific Reports

For decades, Granovetter’s tie strength has been quantified using the frequency of interaction. Yet, frequency does not reflect Granovetter’s initial conception of strength, which is a mix of social dimensions including exchnage of knowledge and provision of support. We used Natural Language Processing to quantify whether text messages convey expressions of knowledge or support, and applied it to a large conversation network from of Reddit users resident in the United States. Borrowing a classic experimental setup, we tested whether the diversity of social connections of Reddit users resident in a specific US state would correlate with the economic opportunities in that state (estimated with GDP per capita). We found that the combination of diversity calculated on the knowledge and support networks correlates much more strongly with GDP than diversity calculated on a network weighted with interaction frequency (R2=0.62 vs. R2=0.30). We also found that the two types of ties differ in their geographical span. Knowledge ties are long-distance (i.e., connecting people living in far-away states), support ties are mostly created among people living close by. Read more in this blogpost.

Two new NERDS urban planning papers: COVID-19 vs. urban form and Micromobility network planning

We are on an urban planning streak, publishing two new papers in Environment and Planning B:

  1. Urban form and COVID-19 cases and deaths in Greater London: An urban morphometric approach, by A. Venerandi, L.M. Aiello, and S. Porta, published in Environment and Planning B

    The COVID-19 pandemic generated a considerable debate in relation to urban density. Many urban planners have advocated for rethinking our cities in ways that can decrease built-up density, in order to curb the spreading of future epidemics. In this work, we show that would be a bad idea. We used urban morphometrics to quantify built-up density in Greater London, and studied its relationship with COVID-19 cases and deaths at the level of MSOAs (small neighborhoods with an average population of ~8000). We found that urban density weakly and negatively correlates with both deaths and cases. The picture above (the low-density areas that some think could save us from contagion) shows the typical area in London with highest occurrence of COVID cases. The widespread belief that COVID cases scale with built-up density was supported mostly by city-level studies. The picture changes when comparing different areas within a city, which has been done for the first time in our study. The moral of the story is that built-up density is different from crowding. Let’s keep that in mind before worsening the urban sprawl of our cities. 
  2. Data-driven micromobility network planning for demand and safety, by P. Folco, L. Gauvin, M. Tizzoni, and M. Szell, published in Environment and Planning B

    In this paper we study how data of micromobility trips and crashes can shape and automatize infrastructure network planning processes. We introduce a parameter that tunes the focus between demand-based and safety-based development, and investigate systematically this tradeoff for the city of Turin. We find that a full focus on demand or safety generates different network extensions in the short term, with an optimal tradeoff in-between. In the long term, our framework improves overall network quality independent of short-term focus. Thus, we show how a data-driven process can provide urban planners with automated assistance for variable short-term scenario planning while maintaining the long-term goal of a sustainable, city-spanning micromobility network.
    See the interactive visualization: http://www.datainterfaces.org/projects/biketracks/#turin

Two new NERDS papers: NFT price dynamics and Online originality

Two new NERDS papers are out – this time both in Scientific Reports:

  1. Heterogeneous rarity patterns drive price dynamics in NFT collections, by A. Mekacher, A. Bracci, M. Nadini, M. Martino, L. Alessandretti, L.M. Aiello & A. Baronchelli, published in Scientific ReportsWe quantify Non Fungible Token (NFT) rarity and investigate how it impacts market behaviour. We show that, on average, rarer NFTs: (i) sell for higher prices, (ii) are traded less frequently, (iii) guarantee higher returns on investment, and (iv) are less risky, i.e., less prone to yield negative returns. The dataset used for the work has been presented as part of a beautiful art exhibition at the MEET Digital Culture Center in Milano.
  2. Posts on central websites need less originality to be noticed, by M. Coscia and C. Vandeweerdt, published in Scientific Reports
    In this paper we study how originality and centrality interact in a nontrivial way, which might explain why originality by itself is not a good predictor of success. We collected data from Reddit on users sharing hyperlinks. We estimated the originality of each post title and the centrality of the website hosting the shared link. We show that the interaction effect exists: if users share content from a central website, originality no longer increases the odds of receiving at least one upvote.
    See more info in Michele’s blogpost: https://www.michelecoscia.com/?p=2205

IC2S2 2023 in Copenhagen!

Copenhagen will host the 9th edition of the International Conference of Computational Social Science (IC2S2) in July 2023, brought here by NERDS & Co!

IC²S² is the premier annual meeting bringing together researchers from different disciplines interested in using computational and data-intensive methods to address societally relevant problems.

The event will be organized jointly between the IT University of Copenhagen (ITU), the Technical University of Denmark (DTU), and the University of Copenhagen (KU). NERDS will have a crucial role in the organization: Luca Aiello will be General Co-Chair, Roberta Sinatra will be Program Co-Chair, and NERDS will be heavily involved in organization and connecting conference participants. The event will take place at the Maersk Tower, a fabulous venue in the heart of the city.

The Maersk Tower in Copenhagen

All previous editions of the conference have been a great success, with hundreds of participants, and we’ll work hard to go above and beyond with the next edition. The conference will feature around 10 keynote talks, 6 tutorials, 200+ contributed presentations, and a 3-day poster session.

Busy attendees during the last two in-presence conferences in Amsterdam and Chicago.

We’re looking forward to welcoming you in Copenhagen next year!