Nicolas Velasquez

Universidad de Atacama

Online extremist movements are increasingly using social media communities to share content, spread their ideologies, recruit members, and mobilize offline activities. In recent years, mainstream platforms, including Twitter and Facebook, have adopted policies to remove or deplatform some of these movements. Yet online extremists are well-known for...

Online hate speech is a critical and worsening problem, with extremists using social media platforms to radicalize recruits and coordinate offline violent events. While much progress has been made in analyzing online hate speech, no study to date has classified multiple types of hate speech across both mainstream and fringe platforms. We conduct a...

Online hate speech is a critical and worsening problem, with extremists using social media platforms to radicalize recruits and coordinate offline violent events. While much progress has been made in analyzing online hate speech, no study to date has classified multiple types of hate speech across both mainstream and fringe platforms. We conduct a...

Ensuring widespread public exposure to best-science guidance is crucial in a crisis, e.g. Covid-19, climate change. Mapping the emitter-receiver dynamics of Covid-19 guidance among 87 million Facebook users, we uncover a multi-sided battle over exposure that gets lost well before the pandemic's official announcement. By the time Covid-19 vaccines e...

We show that malicious COVID-19 content, including racism, disinformation, and misinformation, exploits the multiverse of online hate to spread quickly beyond the control of any individual social media platform. We provide a first mapping of the online hate network across six major social media platforms. We demonstrate how malicious content can tr...

Disrupting the emergence and evolution of potentially violent online extremist movements is a crucial challenge. Extremism research has analyzed such movements in detail, focusing on individual- and movement-level characteristics. But are there system-level commonalities in the ways these movements emerge and grow? Here we compare the growth of the...

Parents - particularly moms - increasingly consult social media for support when taking decisions about their young children, and likely also when advising other family members such as elderly relatives. Minimizing malignant online influences is therefore crucial to securing their assent for policies ranging from vaccinations, masks and social dist...

We show that malicious COVID-19 content, including racism, disinformation, and misinformation, exploits the multiverse of online hate to spread quickly beyond the control of any individual social media platform. We provide a first mapping of the online hate network across six major social media platforms. We demonstrate how malicious content can tr...

Objectives. To understand changes in how Facebook pages frame vaccine opposition. Methods. We categorized 204 Facebook pages expressing vaccine opposition, extracting public posts through November 20, 2019. We analyzed posts from October 2009 through October 2019 to examine if pages’ content was coalescing. Results. Activity in pages promoting vacc...

From the moment the first COVID-19 vaccines are rolled out, there will need to be a large fraction of the global population ready in line. It is therefore crucial to start managing the growing global hesitancy to any such COVID-19 vaccine. The current approach of trying to convince the "no"s cannot work quickly enough, nor can the current policy of...

Many governments have managed to control their COVID-19 outbreak with a simple message: keep the effective '$R$ number' $R<1$ to prevent widespread contagion and flatten the curve. This raises the question whether a similar policy could control dangerous online 'infodemics' of information, misinformation and disinformation. Here we show, using mult...

We show that the eclectic "Boogaloo" extremist movement that is now rising to prominence in the U.S., has a hidden online mathematical order that is identical to ISIS during its early development, despite their stark ideological, geographical and cultural differences. The evolution of each across scales follows a single shockwave equation that acco...

Distrust in scientific expertise1,2,3,4,5,6,7,8,9,10,11,12,13,14 is dangerous. Opposition to vaccination with a future vaccine against SARS-CoV-2, the causal agent of COVID-19, for example, could amplify outbreaks2,3,4, as happened for measles in 20195,6. Homemade remedies7,8 and falsehoods are being shared widely on the Internet, as well as dismis...

A huge amount of potentially dangerous COVID-19 misinformation is appearing online. Here we use machine learning to quantify COVID-19 content among online opponents of establishment health guidance, in particular vaccinations ("anti-vax"). We find that the anti-vax community is developing a less focused debate around COVID-19 than its counterpart,...

We show that malicious COVID-19 content, including hate speech, disinformation, and misinformation, exploits the multiverse of online hate to spread quickly beyond the control of any individual social media platform. Machine learning topic analysis shows quantitatively how online hate communities are weaponizing COVID-19, with topics evolving rapid...

We present preliminary results on the online war surrounding distrust of expertise in medical science -- specifically, the issue of vaccinations. While distrust and misinformation in politics can damage democratic elections, in the medical context it may also endanger lives through missed vaccinations and DIY cancer cures. We find that this online...

Online hate and extremist narratives have been linked to abhorrent real-world events, including a current surge in hate crimes1–6 and an alarming increase in youth suicides that result from social media vitriol⁷; inciting mass shootings such as the 2019 attack in Christchurch, stabbings and bombings8–11; recruitment of extremists12–16, including en...

We quantify how and when extreme subpopulations emerge in a model society despite everyone having the same information and available resources – and show that counterintuitively these extremes will likely be enhanced over time by new social media algorithms designed to reduce division. We verify our analysis mathematically, and show it reproduces (...

Split-belt treadmills that move the legs at different speeds are thought to update internal representations of the environment, such that this novel condition generates a new locomotor pattern with distinct spatio-temporal features compared to those of regular walking. It is unclear the degree to which such recalibration of movements in the spatial...

Split-belt treadmills that move the legs at different speeds are thought to update internal representations of the environment, such that this novel condition generates a new locomotor pattern with distinct spatio-temporal features to those of regular walking. It is unclear the degree to which such recalibration of movements in the spatial and temp...

Online social media allows individuals to cluster around common interests - including hate. We show that tight-knit social clusters interlink to form resilient 'global hate highways' that bridge independent social network platforms, countries, languages and ideologies, and can quickly self-repair and rewire. We provide a mathematical theory that re...

We present a many-body theory that explains and reproduces recent observations of population polarization dynamics, is supported by controlled human experiments, and addresses the controversy surrounding the Internet's impact. It predicts that whether and how a population becomes polarized is dictated by the nature of the underlying competition, ra...

A complete IoT solution for outdoor traceability of mobile things is presented. e system is composed of a mobile embedded system with a GPS/GPRS module (also referred in the article as tracking device) and cloud services. is embedded device has been designed using design for manufacturing, assembly and testing, with low power consumption and low co...

is paper presents an Internet of ings (IoT) approach to Human Activity Recognition (HAR) using remote monitoring of vital signs in the context of a healthcare system for self-managed chronic heart patients. Our goal is to create a HAR-IoT system using learning algorithms to infer the activity done within 4 categories (lie, sit, walk and run) as wel...

El articulo busco comprobar que un uso inadecuado de la informacion en medios de comunicacion puede incrementar riesgos en personas susceptibles a enfermedad mental. Para ello se estudio el efecto de noticias colombianas, tanto nacionales como regionales, que se relacionaban con la palabra suicidio en el 2014. Posteriormente, se analizaron las noti...

Tackling the advance of online threats Online support for adversarial groups such as Islamic State (ISIS) can turn local into global threats and attract new recruits and funding. Johnson et al. analyzed data collected on ISIS-related websites involving 108,086 individual followers between 1 January 1 and 31 August 2015. They developed a statistical...

After a decade long surge in Sino-Latin American trade, the bilateral relationship has gained political and cultural complexity. Recent public opinion polls depict a mildly positive opinion of China in Latin America. Nonetheless, these polls are not well suited to unveiling the framing of anti-Chinese attitudes that are present among the Latin Amer...

Many high-profile societal problems involve an individual or group repeatedly attacking another - from child-parent disputes, sexual violence against women, civil unrest, violent conflicts and acts of terror, to current cyber-attacks on national infrastructure and ultrafast cyber-trades attacking stockholders. There is an urgent need to quantify th...

This Resource Letter provides a guide into the literature on modeling and explaining political conflict, violence, and wars. Although this literature is dominated by social scientists, multidisciplinary work is currently being developed in the wake of myriad methodological approaches that have sought to analyze and predict political violence. The w...

Open Source Indicators (OSI) such as Google Trends (GT) promise to uncover the social dynamics associated with behavior that precede episodes of civil unrest. There are myriad reasons why societies may become unstable: Our analysis does not require or inquire the underlying reasons for discontent but instead takes into account differences associate...