Nudging and corporate environmental responsibility: a natural field experiment

We devise a "nudging" natural field experiment to test the impact of a simple form of advertising on environmentally responsible products with/without the increase of the responsible product price. We find that the simple use of a small shelf poster explaining the importance of buying a green product (with/without a concurring price increase) generates significant changes in market shares for some of the product classes for both food and non-food products. Part of the effect is generated by the reduced price elasticity of consumers to the poster-plus-price-increase treatment

Nudging and corporate environmental responsibility: A natural field experiment

We devise a “nudging” natural field experiment to test the impact of a simple form of advertising on environmentally responsible products with/without the increase of the responsible product price. We find that the simple use of a small shelf poster explaining the importance of buying a green product (with/without a concurring price increase) generates significant changes in market shares for some of the product classes for both food and non-food products. Part of the effect is generated by the reduced price elasticity of consumers to the poster-plus-price-increase treatment

Let us buy sustainable! The impact of cash mobs on sustainable consumption: Experimental results

Cash mob is a practice where groups of people gather at local shops to buy a given product (usually with a strong sustainable feature) and make their decisions visible to the general public. With our paper we aim to assess the effectiveness of the cash mob as a behavioural tool and provide a better understanding of the behavioural triggers of consumers’ decision making process. We run a laboratory experiment where we mimic sustainable consumption and the cash mob treatment is embedded in a sequential game structure with/without an environmental frame. We find that the cash mob treatment has a positive gross effect, that is, the share of sustainable consumers is significantly higher in treated sessions. We also document a significant effect of expectations about the number of those eliciting a sustainable behaviour depending on participants’ previous choices. Our results suggest that cash mob-like mechanisms can help to solve social dilemmas like sustainable consumption with entirely private solutions (not based on punishment like taxes but on positive action), and with no costs for government budgets

dynamic modeling of wind turbines experimental tuning of a multibody model

Abstract This work is part of a research project funded by the Italian Ministry of the University and Research (MIUR), under the call for "National Interest Research Projects 2015 (PRIN 2015)", titled "Smart Optimized Fault Tolerant WIND turbines (SOFTWIND)". Within this project, the research unit of the University of Perugia (UniPG) aims to develop dynamic modeling and simulation methodologies and fatigue behavior evaluation ones for wind turbine as a whole. The development of these methodologies will be aimed at predicting the life of generic wind turbines, also providing important and fundamental parameters for optimizing their control, aimed at reducing the failures of these machines. In the present paper, a small turbine, developed at the Department of Engineering of the University of Perugia, will be analyzed. The multibody modeling technique adopted and the experimental activity conducted in the wind tunnel of UniPG, needed for the tuning of the model, will be described. The analysis of both model behavior and experimental data has allowed for the definition of a robust multibody modeling technique that adopts a freeware code (NREL - FAST), universally considered to be a reference in this field. The goodness of the model guarantees the capabilities of the simulation environment to analyze the real load scenario and the fatigue behavior of this kind of device

Understanding the heterogeneity of COVID-19 deaths and contagions: The role of air pollution and lockdown decisions

The uneven geographical distribution of the novel coronavirus epidemic (COVID-19) in Italy is a puzzle given the intense flow of movements among the different geographical areas before lockdown decisions. To shed light on it, we test the effect of the quality of air (as measured by particulate matter and nitrogen dioxide) and lockdown restrictions on daily adverse COVID-19 outcomes during the first pandemic wave in the country. We find that air pollution is positively correlated with adverse outcomes of the pandemic, with lockdown being strongly significant and more effective in reducing deceases in more polluted areas. Results are robust to different methods including cross-section, pooled and fixed-effect panel regressions (controlling for spatial correlation), instrumental variable regressions, and difference-in-differences estimates of lockdown decisions through predicted counterfactual trends. They are consistent with the consolidated body of literature in previous medical studies suggesting that poor quality of air creates chronic exposure to adverse outcomes from respiratory diseases. The estimated correlation does not change when accounting for other factors such as temperature, commuting flows, quality of regional health systems, share of public transport users, population density, the presence of Chinese community, and proxies for industry breakdown such as the share of small (artisan) firms. Our findings provide suggestions for investigating uneven geographical distribution patterns in other countries, and have implications for environmental and lockdown policies

Finding a Bounded-Degree Expander Inside a Dense One

It follows from the Marcus-Spielman-Srivastava proof of the Kadison-Singer conjecture that if $G=(V,E)$ is a $\Delta$-regular dense expander then there is an edge-induced subgraph $H=(V,E_H)$ of $G$ of constant maximum degree which is also an expander. As with other consequences of the MSS theorem, it is not clear how one would explicitly construct such a subgraph. We show that such a subgraph (although with quantitatively weaker expansion and near-regularity properties than those predicted by MSS) can be constructed with high probability in linear time, via a simple algorithm. Our algorithm allows a distributed implementation that runs in $\mathcal O(\log n)$ rounds and does \bigO(n) total work with high probability. The analysis of the algorithm is complicated by the complex dependencies that arise between edges and between choices made in different rounds. We sidestep these difficulties by following the combinatorial approach of counting the number of possible random choices of the algorithm which lead to failure. We do so by a compression argument showing that such random choices can be encoded with a non-trivial compression. Our algorithm bears some similarity to the way agents construct a communication graph in a peer-to-peer network, and, in the bipartite case, to the way agents select servers in blockchain protocols

Fission studies with 140 MeV α\bm{\alpha}-Particles

Binary fission induced by 140 MeV $\alpha$-particles has been measured for $^{\rm nat}$Ag, $^{139}$La, $^{165}$Ho and $^{197}$Au targets. The measured quantities are the total kinetic energies, fragment masses, and fission cross sections. The results are compared with other data and systematics. A minimum of the fission probability in the vicinity $Z^2/A=24$ is observed.Comment: 4 figures, 2 table