Second Mover Advantage and Bertrand Dynamic Competition: An Experiment

In this paper we provide an experimental test of a dynamic Bertrand duopolistic model, where firms move sequentially and their informational setting varies across different designs. Our experiment is composed of three treatments. In the first treatment, subjects receive information only on the costs and demand parameters and on the price’ choices of their opponent in the market in which they are positioned (matching is fixed); in the second and third treatments, subjects are also informed on the behaviour of players who are not directly operating in their market. Our aim is to study whether the individual behaviour and the process of equilibrium convergence are affected by the specific informational setting adopted. In all treatments we selected students who had previously studied market games and industrial organization, conjecturing that the specific participants’ expertise decreased the chances of imitation in treatment II and III. However, our results prove the opposite: the extra information provided in treatment II and III strongly affects the long run convergence to the market equilibrium. In fact, whilst in the first session, a high proportion of markets converge to the Nash-Bertrand symmetric solution, we observe that a high proportion of markets converge to more collusive outcomes in treatment II and more competitive outcomes in treatment III. By the same token, players’ profits significantly differ in three settings. An interesting point of our analysis relates to the assessment of the individual behavioural rules in the second and third treatments. When information on the behaviour of participants on uncorrelated markets is provided, players begin to adopt mixed behavioural rules, in the sense that they follow myopic best reply rules as long as their profits are in line with the average profits on all markets, and , when their gains fall below that threshold, they start imitating successful strategies adopted on other markets

Diversity and ethics in trauma and acute care surgery teams: results from an international survey

Background Investigating the context of trauma and acute care surgery, the article aims at understanding the factors that can enhance some ethical aspects, namely the importance of patient consent, the perceptiveness of the ethical role of the trauma leader, and the perceived importance of ethics as an educational subject. Methods The article employs an international questionnaire promoted by the World Society of Emergency Surgery. Results Through the analysis of 402 fully filled questionnaires by surgeons from 72 different countries, the three main ethical topics are investigated through the lens of gender, membership of an academic or non-academic institution, an official trauma team, and a diverse group. In general terms, results highlight greater attention paid by surgeons belonging to academic institutions, official trauma teams, and diverse groups. Conclusions Our results underline that some organizational factors (e.g., the fact that the team belongs to a university context or is more diverse) might lead to the development of a higher sensibility on ethical matters. Embracing cultural diversity forces trauma teams to deal with different mindsets. Organizations should, therefore, consider those elements in defining their organizational procedures. Level of evidence Trauma and acute care teams work under tremendous pressure and complex circumstances, with their members needing to make ethical decisions quickly. The international survey allowed to shed light on how team assembly decisions might represent an opportunity to coordinate team member actions and increase performance

The role of immune suppression in COVID-19 hospitalization: clinical and epidemiological trends over three years of SARS-CoV-2 epidemic

Specific immune suppression types have been associated with a greater risk of severe COVID-19 disease and death. We analyzed data from patients >17 years that were hospitalized for COVID-19 at the “Fondazione IRCCS Ca′ Granda Ospedale Maggiore Policlinico” in Milan (Lombardy, Northern Italy). The study included 1727 SARS-CoV-2-positive patients (1,131 males, median age of 65 years) hospitalized between February 2020 and November 2022. Of these, 321 (18.6%, CI: 16.8–20.4%) had at least one condition defining immune suppression. Immune suppressed subjects were more likely to have other co-morbidities (80.4% vs. 69.8%, p < 0.001) and be vaccinated (37% vs. 12.7%, p < 0.001). We evaluated the contribution of immune suppression to hospitalization during the various stages of the epidemic and investigated whether immune suppression contributed to severe outcomes and death, also considering the vaccination status of the patients. The proportion of immune suppressed patients among all hospitalizations (initially stable at <20%) started to increase around December 2021, and remained high (30–50%). This change coincided with an increase in the proportions of older patients and patients with co-morbidities and with a decrease in the proportion of patients with severe outcomes. Vaccinated patients showed a lower proportion of severe outcomes; among non-vaccinated patients, severe outcomes were more common in immune suppressed individuals. Immune suppression was a significant predictor of severe outcomes, after adjusting for age, sex, co-morbidities, period of hospitalization, and vaccination status (OR: 1.64; 95% CI: 1.23–2.19), while vaccination was a protective factor (OR: 0.31; 95% IC: 0.20–0.47). However, after November 2021, differences in disease outcomes between vaccinated and non-vaccinated groups (for both immune suppressed and immune competent subjects) disappeared. Since December 2021, the spread of the less virulent Omicron variant and an overall higher level of induced and/or natural immunity likely contributed to the observed shift in hospitalized patient characteristics. Nonetheless, vaccination against SARS-CoV-2, likely in combination with naturally acquired immunity, effectively reduced severe outcomes in both immune competent (73.9% vs. 48.2%, p < 0.001) and immune suppressed (66.4% vs. 35.2%, p < 0.001) patients, confirming previous observations about the value of the vaccine in preventing serious disease

Gender Effects, Culture and Social Influence in the Dictator Game: An Italian Study

There is little consensus on whether women are more generous than men; some research results indicate a higher propensity towards giving of female dictators, whilst others suggest the opposite. Two explanations have been put forward. According to the first one, women are more generous than men and the conflicting results are due to the way preferences are elicited (Eckel and Grossman, 2002), since women are more sensitive to “social cues” and their preferences are more “malleable” (Croson and Gneezy, 2009). According to the second one, the institutional culture and the role women have in society are key elements in shaping gender differences in preferences. In fact, in matrilineal societies (Gong et al.; 2014; Gneezy et al.; 2009), women are self-oriented, more competitive and less generous than men, since they have an important role as economic decision makers in the family and the society. We test these alternative hypotheses running Dictators experiments in Italy, a western country with a matrilineal culture, introducing – at the same time – social influence in the design. We find more support to the hypothesis on the cultural role in shaping preferences, rather than the effects of social influence. JE

Second Mover Advantage and Bertrand Dynamic Competition: An Experiment

In this paper we provide an experimental test of a dynamic Bertrand duopolistic model, where firms move sequentially and their informational setting varies across different designs. Our experiment is composed of three treatments. In the first treatment, subjects receive information only on the costs and demand parameters and on the price’ choices of their opponent in the market in which they are positioned (matching is fixed); in the second and third treatments, subjects are also informed on the behaviour of players who are not directly operating in their market. Our aim is to study whether the individual behaviour and the process of equilibrium convergence are affected by the specific informational setting adopted. In all treatments we selected students who had previously studied market games and industrial organization, conjecturing that the specific participants’ expertise decreased the chances of imitation in treatment II and III. However, our results prove the opposite: the extra information provided in treatment II and III strongly affects the long run convergence to the market equilibrium. In fact, whilst in the first session, a high proportion of markets converge to the Nash-Bertrand symmetric solution, we observe that a high proportion of markets converge to more collusive outcomes in treatment II and more competitive outcomes in treatment III. By the same token, players’ profits significantly differ in three settings. An interesting point of our analysis relates to the assessment of the individual behavioural rules in the second and third treatments. When information on the behaviour of participants on uncorrelated markets is provided, players begin to adopt mixed behavioural rules, in the sense that they follow myopic best reply rules as long as their profits are in line with the average profits on all markets, and , when their gains fall below that threshold, they start imitating successful strategies adopted on other markets.price competition, learning, strategic information.

Third party punishment and criminal behavior: an experiment with the Italian Camorra prison inmates

In this paper, we report the results of two experiments, each comprising two designs (a prisoner dilemma and a third party punishment; Fehr et al. 2004). The experiments were conducted with a sample of university students and a sample of Camorra prison inmates, both coming from the same Italian region. Our research hypothesis is that there are consistent differences in cooperative and sanctioning behavior between the two samples. The presence of these differences would justify the claim that economic analyses of crime must be integrated with a behavioral perspective. The results of the experiments fully support our research hypothesis, as Camorra inmates exhibit higher propensity to cooperate and to punish defecting behavior