Leveraging digital and computational demography for policy insights

Situated at the intersection of the computational and demographic sciences, digital and computational demography explores how new digital data streams and computational methods advance the understanding of population dynamics, along with the impacts of digital technologies on population outcomes, e.g. linked to health, fertility and migration. Encompassing the data, methodological and social impacts of digital technologies, we outline key opportunities provided by digital and computational demography for generating policy insights. Within methodological opportunities, individual-level simulation approaches, such as microsimulation and agent-based modelling, infused with different data, provide tools to create empirically informed synthetic populations that can serve as virtual laboratories to test the impact of different social policies (e.g. fertility policies, support for the elderly or bereaved people). Individual-level simulation approaches allow also to assess policy-relevant questions about the impacts of demographic changes linked to ageing, climate change and migration. Within data opportunities, digital trace data provide a system for early warning with detailed spatial and temporal granularity, which are useful to monitor demographic quantities in real time or for understanding societal responses to demographic change. The demographic perspective highlights the importance of understanding population heterogeneity in the use and impacts of different types of digital technologies, which is crucial towards building more inclusive digital spaces

Reliance on scientists and experts during an epidemic: Evidence from the COVID-19 outbreak in Italy

Research suggests trust in experts and authorities are important correlates of compliance with public health measures during infectious disease outbreaks. Empirical evidence on the dynamics of reliance on scientists and public health authorities during the early phases of an epidemic outbreak is limited. We examine these processes during the COVID-19 outbreak in Italy by leveraging data from Twitter and two online surveys, including a survey experiment. We find that reliance on experts followed a curvilinear path. Both Twitter and survey data showed initial increases in information-seeking from expert sources in the three weeks after the detection of the first case. Consistent with these increases, knowledge about health information linked to COVID-19 and support for containment measures was widespread, and better knowledge was associated with stronger support for containment policies. Both knowledge and containment support were positively associated with trust in science and public health authorities. However, in the third week after the outbreak, we detected a slowdown in responsiveness to experts. These processes were corroborated with a survey experiment, which showed that those holding incorrect beliefs about COVID-19 gave no greater – or even lower – importance to information when its source was stated as coming from experts than when the source was unstated. Our results suggest weakened trust in public health authorities with prolonged exposure to the epidemic as a potential mechanism for this effect. Weakened responsiveness to expert sources may increase susceptibility to misinformation and our results call for efforts to sustain trust in adapting public health response

Demographic inequalities in digital spaces in China: The case of Weibo

We provide the first systematic, large-scale exploration of user counts by age, gender, and location on Weibo, the world's largest microblogging platform, using data from its advertising platform. Digital platforms potentially give access to information, economic opportunities, and social participation to underserved groups, and can be used for information dissemination during emergency situations and humanitarian response. The trace data that they produce is potentially more timely, of higher spatial or temporal resolution, and available for difficult-to-reach populations, than data from traditional sources. Whether this potential is fully realized however depends on who actually participates in these online spaces. We contribute to a growing body of research investigating the demographic characteristics of social media platforms, and on the population generalizability of digital trace data in non-Western, non-English-language contexts. We show that Weibo users are disproportionately young, female, and urban. Use of Weibo is higher in areas that are more economically prosperous and with a more educated population

A global assessment of the impact of violence on lifetime uncertainty

Uncertainty around age at death, or lifetime uncertainty, is a key public health indicator and a marker of inequality in survival. How does the extent of violence affect lifetime uncertainty? We address this question by quantifying the impact of violence on dispersion in the ages at death, the metric most used to measure lifetime uncertainty. Using mortality data from the Global Burden of Disease Study and the Internal Peace Index between 2008 and 2017, we find that the most violent countries are also those with the highest lifetime uncertainty. In the Middle East, conflict-related deaths are the largest contributor to lifetime uncertainty. In Latin America, a similar pattern is attributable to homicides. The effects are larger in magnitude for men, but the consequences remain considerable for women. Our study points to a double burden of violence on longevity: Not only does violence shorten individual lives, but it also makes the length of life less predictable

Demographic change and increasing late singlehood in East Asia, 2010-2050

Background: Marriage is a central institution for social reproduction in East Asia. Until the 1970s and 1980s, marriage across much of East Asia was early and universal. In recent decades, though, this pattern has begun shifting to one of later and less marriage. Objective: We explore the long-term implications for universal marriage patterns of future demographic change in marriage markets in the context of prevailing marriage norms by projecting trends in late singlehood (ages 45 to 49) in four East Asian societies (China, South Korea, Taiwan, and Japan). Methods: We estimate forces of attraction to characterize marriage matching norms by age and education across these different societies by drawing on large-scale population data. Next, we develop counterfactual scenarios in which we apply contemporary norms to future population structures in these societies, as well as scenarios based on more gender-symmetrical matching norms to examine how populations who have never been married by ages 45 to 49 would evolve. Results: Our projections indicate that in the coming decades there will be a substantial increase in late singlehood across all these societies relative to their 2010 levels. These increases in singlehood are driven by forthcoming demographic changes in the marriage market that intensify the effects of prevailing matching norms. These increases are notable in Taiwan and South Korea, where recent data indicate generalized weak propensities to marry in current norms. While a shift toward greater gender symmetry in matching norms would reverse gender gaps between men and women in nonmarriage, it would have little impact on the overall projected proportions of singles by ages 45 to 49. Conclusions: If prevailing norms in each of these contexts continue, the universality of marriage will be substantially eroded in the coming decades, even if norms become more gender symmetrical. The extent to which nonmarital cohabitation and childbearing emerge in the future will determine how marriage will influence fertility trends, population growth, aging, and social reproduction. Contribution: For the first time, we project the implications for universal marriage of recent shifts in marriage norms and demographic change in East Asian countries

A global assessment of the impact of violence on lifetime uncertainty.

Uncertainty around age at death, or lifetime uncertainty, is a key public health indicator and a marker of inequality in survival. How does the extent of violence affect lifetime uncertainty? We address this question by quantifying the impact of violence on dispersion in the ages at death, the metric most used to measure lifetime uncertainty. Using mortality data from the Global Burden of Disease Study and the Internal Peace Index between 2008 and 2017, we find that the most violent countries are also those with the highest lifetime uncertainty. In the Middle East, conflict-related deaths are the largest contributor to lifetime uncertainty. In Latin America, a similar pattern is attributable to homicides. The effects are larger in magnitude for men, but the consequences remain considerable for women. Our study points to a double burden of violence on longevity: Not only does violence shorten individual lives, but it also makes the length of life less predictable

Life expectancy changes since COVID-19.

The COVID-19 pandemic triggered an unprecedented rise in mortality that translated into life expectancy losses around the world, with only a few exceptions. We estimate life expectancy changes in 29 countries since 2020 (including most of Europe, the United States and Chile), attribute them to mortality changes by age group and compare them with historic life expectancy shocks. Our results show divergence in mortality impacts of the pandemic in 2021. While countries in western Europe experienced bounce backs from life expectancy losses of 2020, eastern Europe and the United States witnessed sustained and substantial life expectancy deficits. Life expectancy deficits during fall/winter 2021 among people ages 60+ and <60 were negatively correlated with measures of vaccination uptake across countries (r60+ = -0.86; two-tailed P < 0.001; 95% confidence interval, -0.94 to -0.69; r<60 = -0.74; two-tailed P < 0.001; 95% confidence interval, -0.88 to -0.46). In contrast to 2020, the age profile of excess mortality in 2021 was younger, with those in under-80 age groups contributing more to life expectancy losses. However, even in 2021, registered COVID-19 deaths continued to account for most life expectancy losses

Quantifying impacts of the COVID-19 pandemic through life-expectancy losses: a population-level study of 29 countries.

BACKGROUND: Variations in the age patterns and magnitudes of excess deaths, as well as differences in population sizes and age structures, make cross-national comparisons of the cumulative mortality impacts of the COVID-19 pandemic challenging. Life expectancy is a widely used indicator that provides a clear and cross-nationally comparable picture of the population-level impacts of the pandemic on mortality. METHODS: Life tables by sex were calculated for 29 countries, including most European countries, Chile and the USA, for 2015-2020. Life expectancy at birth and at age 60 years for 2020 were contextualized against recent trends between 2015 and 2019. Using decomposition techniques, we examined which specific age groups contributed to reductions in life expectancy in 2020 and to what extent reductions were attributable to official COVID-19 deaths. RESULTS: Life expectancy at birth declined from 2019 to 2020 in 27 out of 29 countries. Males in the USA and Lithuania experienced the largest losses in life expectancy at birth during 2020 (2.2 and 1.7 years, respectively), but reductions of more than an entire year were documented in 11 countries for males and 8 among females. Reductions were mostly attributable to increased mortality above age 60 years and to official COVID-19 deaths. CONCLUSIONS: The COVID-19 pandemic triggered significant mortality increases in 2020 of a magnitude not witnessed since World War II in Western Europe or the breakup of the Soviet Union in Eastern Europe. Females from 15 countries and males from 10 ended up with lower life expectancy at birth in 2020 than in 2015