One method that has been proposed for the measurement of sustainability is Data Envelopment Analysis (DEA). Despite its advantages, the method has limitations: First, the efficiency of Decision-Making Units is calculated with weights that are favorable to themselves, which might be unrealistic, and second, it cannot account for different perceptions of sustainability; since there is not an established and unified definition, each analyst can use different data and variations that produce different results. The purpose of the current paper is twofold: (a) to propose an alternative, multi-dimensional DEA model that handles weight flexibility using a different metric (an alternative optimization criterion) and (b) the inclusion of a computational stage that attempts to incorporate different perceptions in the measurement of sustainability and integrates machine learning to explore country sustainability composite indices under different perceptions and assumptions. This approach offers insights in areas such as feature selection and increases the trust in the results by exploiting an inclusive approach to the calculations. The method is used to calculate the sustainability of the 28 EU countries.

The discourse surrounding digital transformation (DT) and sustainable development (SD) is pervasive in contemporary business and organizational operations, with both processes considered indispensable for sustainability. The success or failure of these endeavors hinges significantly on factors such as the behavior and skill sets of individuals within organizations. Thus, the purpose of the paper is twofold: to investigate the perceptions of organizations on digital transformation and sustainable development with regards to skills and education, and, secondly, to use the insights from these perceptions as a starting point for the use of systems thinking as a tool that could assist in achieving these states. To achieve the objective, a research effort was conducted that included desktop research, interviews with experts, and the development of a survey that was disseminated across Europe with questions on digital transformation and sustainable development. Finally, a general causal loop diagram was designed, illustrating the processes of digital transformation and sustainable development within organizations from a top-down view. The study reveals commonalities between DT and SD, recognizing both processes as advantageous with shared deficiencies in specific skill sets. It highlights a synergistic relationship between initiating DT and fostering SD activities. Furthermore, the research underscores the temporal aspects of these processes, acknowledging delayed positive effects and immediate implementation costs that challenge decision-makers to balance long-term benefits with short-term viability. In conclusion, the exploration emphasizes the dynamic nature of DT and SD, urging continual attention to the evolving landscape and the imperative for a shared understanding within organizational contexts.

One of the most challenging issues that policy makers will face in the near future is population ageing and its consequences in pension systems. The purpose of the paper is to investigate the effect of the increase in the retirement age on the pension scheme of Greece, by also taking into account social unrest that can inhibit the policy implementation. A model of Greece's pension scheme was modelled, using the methodology of system dynamics. The results showed that the increase in retirement age is not as effective as regarded in real world and under appropriate conditions, the pension scheme could be sustainable without raising the retirement age.

This paper is based on SUSTAIN, an ERASMUS+ project with an innovative perspective on urban transportation, and its target is to promote the importance of sustainability on the everyday problem of urban transportation among the students of higher education (and not only), who are the policy makers of tomorrow. In order to achieve its goals, the research team is currently developing a course that will be based on an interactive serious board game with an analytical style of education. SUSTAIN’s purpose is to create a game that will allow students to learn about transportation sustainability and societal metabolism through playing. The project partners develop small and illustrative simulation models, which will make the definitions more concrete and allow students to experiment largely in a consequence-free environment. The simulation models can be used to identify scenario exemplars on how we can achieve sustainable urban transportation and consequently a balanced societal metabolism, while on the same time taking into account formal decision making processes. In this paper, we are going to explain a Stocks ---amp--- Flows Diagram for the above mentioned model, with a system dynamics approach.

The objective of this chapter is the development of a System Dynamics model for the study of the milk supply chain and how an extreme event can affect its behavior. A simple interface is developed that can be used to increase the ease of communication and provide an interactive approach to the decision-making process. The model contains three echelons: farmers, processors and retailers. The main results show that under normal circumstances, the behavior of the system reaches equilibrium after a few oscillations. However, these oscillations can be smoothed out if the adjustment time of the order placement is increased. Under an extreme event that reduces the demand for milk, behavior changes and the system remains in dis-equilibrium for the entire simulation. Once again, adjustment times remain the leverages that can influence and mitigate those negative effects. Finally, a more robust and collaborative decision-making process among the actors of the chain could be beneficial for all not only under normal circumstances, but also in the presence of extreme uncertainty.