Josep Tomas-Porresi (University of Turin) and Isabel Rodríguez (Collegio Carlo Alberto)

Postdocs e Rtda

Josep Tomas-Porresi (University of Turin)

“Self-selection and learning in sustainable innovations”

Abstract: This paper investigates the mechanisms driving firms to locate in sustainable markets, focusing on self-selection patterns and the dynamics generated by the learning effects related to the development of sustainable innovations. The theoretical analysis is developed within a monopolistic competition framework with heterogeneous firms and consumers with varying sustainability preferences. Then, its core principles are empirically tested using firm-level data and a system of dynamic models, revealing a significant and positive relationship between past productivity and both the likelihood and intensity of sustainable innovations. Additionally, the outcomes demonstrate two sources of learning effects, one driving firms to persist in developing sustainable innovations, simultaneously increasing their quality, and another enhancing firm productivity once firms develop sustainable innovations. However, the learning returns on productivity are only obtained when there is an increase in the sustainability preferences of the rest of the economy. At their core, the market incentives driving firms to innovate sustainably are based on the trade-off between the costs associated with sustainable innovations and a firm’s ability to exploit their market returns. Then, the learning effects consolidate the long-term comparative advantages in sustainable and non-sustainable markets when the social focus on sustainability becomes more intense.

Isabel Rodríguez (Collegio Carlo Alberto)

“Outgroup hostility across six social identity contexts”

Abstract: Partisan identity has increasingly shaped social divisions in Western societies, fostering strong in-group bias and hostility toward political opponents. This phenomenon is known as partyism. Research on partyism largely examines its macro-level impact and development, but the underlying micro-level mechanisms remain underexplored. Two key factors explain the dominance of partyism over divisions based on race or religion: first, societal norms discourage prejudice based on race or gender but permit political hostility; second, political affiliation is perceived as a choice, making individuals more accountable for their views. These factors likely reinforce each other, influencing norms and behavior. Using the ascribed-achieved identity framework, this study examines why political identity is uniquely divisive. In laboratory experiments, discrimination and social norms were tested in the contexts of politics, religion, and football. Results showed lower discrimination against religious outgroups compared to political or football affiliations. A survey experiment conducted on 3,000 Spaniards further explored the continuum of identity perception, revealing that politics is viewed as the most choice-driven identity, while gender and nationality are seen as the least. These findings demonstrate that normative permissiveness of discrimination is higher for achieved identities, like politics, than for ascribed ones, offering insights into the salience of partisan identity and its divisive effects in modern societies.

Joint work with Luis Miller and Tom Lane