Data-Powered Positive Deviance during the SARS-CoV-2 Pandemic—An Ecological Pilot Study of German Districts

We introduced the mixed-methods Data-Powered Positive Deviance (DPPD) framework as a potential addition to the set of tools used to search for effective response strategies against the SARS-CoV-2 pandemic. For this purpose, we conducted a DPPD study in the context of the early stages of the German SARS-CoV-2 pandemic. We used a framework of scalable quantitative methods to identify positively deviant German districts that is novel in the scientific literature on DPPD, and subsequently employed qualitative methods to identify factors that might have contributed to their comparatively successful reduction of the forward transmission rate. Our qualitative analysis suggests that quick, proactive, decisive, and flexible/pragmatic actions, the willingness to take risks and deviate from standard procedures, good information flows both in terms of data collection and public communication, alongside the utilization of social network effects were deemed highly important by the interviewed districts. Our study design with its small qualitative sample constitutes an exploratory and illustrative effort and hence does not allow for a clear causal link to be established. Thus, the results cannot necessarily be extrapolated to other districts as is. However, the findings indicate areas for further research to assess these strategies’ effectiveness in a broader study setting. We conclude by stressing DPPD’s strengths regarding replicability, scalability, adaptability, as well as its focus on local solutions, which make it a promising framework to be applied in various contexts, e.g., in the context of the Global South.

How individuals change language

Languages emerge and change over time at the population level though interactions between individual speakers. It is, however, hard to directly observe how a single speaker’s linguistic innovation precipitates a population-wide change in the language, and many theoretical proposals exist. We introduce a very general mathematical model that encompasses a wide variety of individual-level linguistic behaviours and provides statistical predictions for the population-level changes that result from them. This model allows us to compare the likelihood of empirically-attested changes in definite and indefinite articles in multiple languages under different assumptions on the way in which individuals learn and use language. We find that accounts of language change that appeal primarily to errors in childhood language acquisition are very weakly supported by the historical data, whereas those that allow speakers to change incrementally across the lifespan are more plausible, particularly when combined with social network effects.

Social networks, adoption of improved variety and household welfare: evidence from Ghana

In this study, we examine the effects of own and peer adoption of improved soybean variety on household yields and food and nutrient consumption, using observational data from Ghana. We employ the marginal treatment effect approach to account for treatment effect heterogeneity across households and a number of identification strategies to capture social network effects. Our empirical results show that households with higher unobserved gains are more likely to adopt because of their worse outcomes when not adopting. We also find strong peer adoption effect on own yield, only when the household is also adopting, and on food and nutrient consumption when not adopting. However, the peer adoption effect on consumption attenuates when the household adopts the improved variety. Furthermore, our findings reveal that adoption tends to equalise households in terms of observed and unobserved gains on consumption and can thus serve as a mechanism for promoting food security and nutrition in this area.

Social Network Effects in Developing Countries

How do social networks influence and moderate electoral persuasion in developing countries? An extensive literature shows that social networks are important for understanding electoral persuasion in established democracies. At the same time, these theories might not necessarily apply to democracies in the developing world, particularly when they are characterized by clientelism, coercion, and other modes of political engagement outside of formal democratic institutions. In such contexts, networks can matter for politics in different, and sometimes unexpected, ways. In surveying the literature, this chapter dentifies three general functions of networks that are important for understanding electoral persuasion behavior in developing countries: (i) information diffusion; (ii) social persuasion; and (iii) coordination and enforcement. The chapter explores the implications of these network mechanisms by exploring the roles of both voter and politician networks.