This article describes a new release of the Social Connectedness Index (SCI), a large-scale measure of social ties across geographic locations constructed from Facebook friendship links. The newly available SCI data have substantially expanded global coverage and finer geographic resolution than prior versions, and provide measures of social connectedness for national and subnational units across 178 countries. The SCI dataset is based on Facebook friendship networks from January 2026 and is freely available through the Humanitarian Data Exchange. This data descriptor details the methodology used to construct the measure, the structure of the SCI dataset, and its geographic coverage at various granularities.

Used a cohort difference-in-differences design and a nationally representative panel of 1.3 million Indians (2014–2024) to estimate the effects of caste- and income-based affirmative action reforms on educational attainment, finding that expanded caste-based reservations increased schooling by 0.26–0.88 years among newly eligible students.

Used an IV framework leveraging drought exposure and its interaction with school meal provision to identify the effect of India’s Mid-Day Meal Scheme on standardized academic outcomes, using nationally representative household survey data; found no statistically significant effects on composite or subject-specific test scores.

Used India’s 2016 demonetization as a natural experiment and conducted complementary survey and pilot field experiments to examine how payment methods affect consumption, finding a negative association between digital payment adoption and aggregate consumption but contrasting experimental estimates of spending differences across payment methods.

Used panel data from 43 countries and a synthetic difference-in-differences design to estimate the effect of India’s 2016 demonetization on tax revenue, finding no statistically significant increase in tax collection relative to synthetic control.

Conducted comparative case studies of populist leaders using process tracing, cross-country tax data, public opinion polls, and computational text analysis of speeches and manifestos; found evidence that right-wing populists’ use of progressive taxation rhetoric varies with the political salience of taxation.

What are the spatial and demographic determinants of Hindu-Muslim tensions in India? Does the case of communal violence in India align with the primordialist or the instrumentalist account of ethnic conflict? Methodology: Geospatial analysis using ArcGIS.

Designed a behavioral survey experiment to test how tax-paying status and effective tax rates shape citizens’ expectations of government, using a pilot randomized study of 50 undergraduates that found higher expected government transfers among participants assigned to pay taxes and those facing higher effective tax rates.

How closely is vegetarianism/veganism linked to leftism and to what extent is carnism linked to right-wing tendencies? Methodology: Survey experiment in the US and India using right-wing authoritarianism questionnaire, social dominance orientation questionnaire, and meat eating justification scale.