Chronicle of a Pandemic Foretold. CEPS Policy Insights No 2020-05 / March 2020

In just a few weeks, COVID-19 appeared in China and quickly spread to the rest of the world, including Europe and the United States. Many have rushed to describe the outbreak as a ‘black swan’ – an unpredictable event with extremely severe consequences. However, COVID-19 was not only predictable ex post: it was amply predicted ex ante. This allows us to draw some preliminary lessons: • First, economic policy will need to shift from its current focus on efficiency, towards a greater emphasis on resilience and sustainability. • Second, a more centralised governance to address health emergencies is needed. • Third, Europe should create a centre for the prevention of large-scale risks. • Fourth, digital technologies, if handled with care, can be an important part of both a mitigation and a response strategy. • Fifth, Europe should improve its science advice and communication functions. Finally, there are many ways to pursue enhanced resilience and responsiveness, but not all of them are compatible with sustainability and democratic values. The challenge is to find an adequate policy mix, which safeguards individual rights and liberties, protects the economy, and at the same time strengthens government preparedness for cases of epidemics and pandemics

Axial and Vector Correlator Mixing in Hot and Dense Hadronic Matter

We study the manifestations of chiral symmetry restoration which have a significance for the parity mixing. Restricting to pions and nucleons we establish a formalism for the expression of the vector correlator, which displays the mixing of the axial correlator into the vector one and unifies the cases of the heat bath and the dense medium. We give examples of mixing cross-sections. We also establish a link between the energy integrated mixing cross-sections and the pion scalar density which governs the quenching factors of coupling constants, such as the pion decay one, as well as the quark condensate evolution.Comment: 12 pages, Latex, 4 PostScript Figure

Nonparametric Identification and Estimation of Nonadditive Hedonic Models

This paper studies the identification and estimation of preferences and technologies in equilibrium hedonic models. In it, we identify nonparametric structural relationships with nonadditive heterogeneity. We determine what features of hedonic models can be identified from equilibrium observations in a single market under weak assumptions about the available information. We then consider use of additional information about structural functions and heterogeneity distributions. Separability conditions facilitate identification of consumer marginal utility and firm marginal product functions. We also consider how identification is facilitated using multimarket data.hedonic models, hedonic equilibrium, nonadditive models, identification, non-parametric estimation

Global Patterns of Synchronization in Human Communications

Social media are transforming global communication and coordination. The data derived from social media can reveal patterns of human behavior at all levels and scales of society. Using geolocated Twitter data, we have quantified collective behaviors across multiple scales, ranging from the commutes of individuals, to the daily pulse of 50 major urban areas and global patterns of human coordination. Human activity and mobility patterns manifest the synchrony required for contingency of actions between individuals. Urban areas show regular cycles of contraction and expansion that resembles heartbeats linked primarily to social rather than natural cycles. Business hours and circadian rhythms influence daily cycles of work, recreation, and sleep. Different urban areas have characteristic signatures of daily collective activities. The differences are consistent with a new emergent global synchrony that couples behavior in distant regions across the world. A globally synchronized peak that includes exchange of ideas and information across Europe, Africa, Asia and Australasia. We propose a dynamical model to explain the emergence of global synchrony in the context of increasing global communication and reproduce the observed behavior. The collective patterns we observe show how social interactions lead to interdependence of behavior manifest in the synchronization of communication. The creation and maintenance of temporally sensitive social relationships results in the emergence of complexity of the larger scale behavior of the social system.Comment: 20 pages, 12 figures. arXiv admin note: substantial text overlap with arXiv:1602.0621