Author Archives: luai

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!

Luca Aiello wins Carlsberg Young Researcher Fellowships

Luca Aiello was one of the recipients of this year’s Carlsberg Young Researcher Fellowships.


The Carlsberg Young Researcher Fellowship funds three-year fellowships for newly appointed tenured associate professors to establish an independent research group and forming an international network.

Luca’s winning proposal was awarded with DKK 5M:
COCOONS: COllective COordination through ONline Social media

In the coming decades, a defining task for humanity will be to solve global challenges through mass coordination. The goal of the project is to unveil the prime elements of social interactions that enable spontaneous coordination in the face of social dilemmas. It will do so by quantifying fundamental dimensions of social interactions with Natural Language Processing algorithms applied to online social media conversations, and to leverage principles from complex systems science to find how these dimensions are linked to cooperation outcomes in social networks.

We are excited about Luca’s success and are looking forward to welcome one new PhD student and two postdocs that will be recruited starting October 2022. Stay tuned for upcoming job calls.

Two new NERDS papers: NFT market and Pearson correlations on networks

Two new papers from the NERDS crew!

    1. Mapping the NFT revolution: market trends, trade networks, and visual features, by M. Nadini, L. Alessandretti, F. Di Giacinto, M. Martino, L.M. Aiello, A. Baronchelli, published in Scientific Reports

      Luca and collaborators performed the first large-scale analysis of the market of Non Fungible Tokens (NFTs) since its birth. The looked at 6.1 million trades of 4.7 million NFTs to learn about market, traders, visual features and price prediction. The dataset they collected is available. Learn more on this blogpost from the Alan Turing Institute.
      Also, watch the accompanying video: https://www.youtube.com/watch?v=KyIITtPKJbY
    2. Pearson correlations on complex networks, by M. Coscia, published in Journal of Complex Networks
       

       
      Estimating the correlation between two processes happening on the same network is therefore an important problem with a number of applications. However, at present there is no way to do so: current methods to estimate the correlation between two processes happening on the same network either correlate a network with itself, a single process with the network structure, or calculate a network distance between two processes. To fill this gap, Michele created a new method to extend the Pearson correlation coefficient to work on complex networks, and showed its usefulness in tasks related to social network analysis and economics. Learn more on this blogpost.