President Biden and State Governors: two years of a positive old-style political dialogue

The article discusses the institutional relationship between the Biden administration and State governors over the first two years of the Presidency, by also highlighting some of the differences in the interplay of federal and state actors in comparison with the Presidency of Donald Trump

Ex malo, bonum? Dilemmas (and Opportunities) as a result of Dobbs.

Il presente contributo si propone di ripercorrere le tappe fondamentali della complessa e critica affermazione giurisprudenziale del diritto all'interruzione volontaria della gravidanza nell'esperienza statunitense, cercando di evidenziare sinteticamente almeno tre elementi: (a) la difficoltà politico-sociale che si riscontra oggi nella ricerca di un nuovo equilibrio politico-giuridico da stabilire a livello federale; (b) il percorso della "defederalizzazione" dei diritti come strumento sempre utile per porre questioni cruciali ai cittadini di uno Stato federale; infine (c) evidenziare le potenziali opportunità offerte dalla sentenza Dobbs v. Jackson Women's Health Organization del 2022 per ridurre la po-larizzazione e lo scontro socio-politico

Parliamentary opposition in the Baltic states’ experience: problems and challenges in the face of the Westminster model

Questo contributo si propone di evidenziare le analogie e le differenze nella tradizione giuridica e nello sviluppo delle istituzioni parlamentari, in particolare sul tema dell'opposizione parlamentare, per quanto riguarda gli Stati baltici di Estonia, Lettonia e Lituania

Information Spreading in Stationary Markovian Evolving Graphs

Markovian evolving graphs are dynamic-graph models where the links among a fixed set of nodes change during time according to an arbitrary Markovian rule. They are extremely general and they can well describe important dynamic-network scenarios. We study the speed of information spreading in the "stationary phase" by analyzing the completion time of the "flooding mechanism". We prove a general theorem that establishes an upper bound on flooding time in any stationary Markovian evolving graph in terms of its node-expansion properties. We apply our theorem in two natural and relevant cases of such dynamic graphs. "Geometric Markovian evolving graphs" where the Markovian behaviour is yielded by "n" mobile radio stations, with fixed transmission radius, that perform independent random walks over a square region of the plane. "Edge-Markovian evolving graphs" where the probability of existence of any edge at time "t" depends on the existence (or not) of the same edge at time "t-1". In both cases, the obtained upper bounds hold "with high probability" and they are nearly tight. In fact, they turn out to be tight for a large range of the values of the input parameters. As for geometric Markovian evolving graphs, our result represents the first analytical upper bound for flooding time on a class of concrete mobile networks.Comment: 16 page

Stabilizing Consensus with Many Opinions

We consider the following distributed consensus problem: Each node in a complete communication network of size $n$ initially holds an \emph{opinion}, which is chosen arbitrarily from a finite set $\Sigma$. The system must converge toward a consensus state in which all, or almost all nodes, hold the same opinion. Moreover, this opinion should be \emph{valid}, i.e., it should be one among those initially present in the system. This condition should be met even in the presence of an adaptive, malicious adversary who can modify the opinions of a bounded number of nodes in every round. We consider the \emph{3-majority dynamics}: At every round, every node pulls the opinion from three random neighbors and sets his new opinion to the majority one (ties are broken arbitrarily). Let $k$ be the number of valid opinions. We show that, if $k \leqslant n^{\alpha}$, where $\alpha$ is a suitable positive constant, the 3-majority dynamics converges in time polynomial in $k$ and $\log n$ with high probability even in the presence of an adversary who can affect up to $o(\sqrt{n})$ nodes at each round. Previously, the convergence of the 3-majority protocol was known for $|\Sigma| = 2$ only, with an argument that is robust to adversarial errors. On the other hand, no anonymous, uniform-gossip protocol that is robust to adversarial errors was known for $|\Sigma| > 2$

Self-Stabilizing Repeated Balls-into-Bins

We study the following synchronous process that we call "repeated balls-into-bins". The process is started by assigning $n$ balls to $n$ bins in an arbitrary way. In every subsequent round, from each non-empty bin one ball is chosen according to some fixed strategy (random, FIFO, etc), and re-assigned to one of the $n$ bins uniformly at random. We define a configuration "legitimate" if its maximum load is $\mathcal{O}(\log n)$. We prove that, starting from any configuration, the process will converge to a legitimate configuration in linear time and then it will only take on legitimate configurations over a period of length bounded by any polynomial in $n$, with high probability (w.h.p.). This implies that the process is self-stabilizing and that every ball traverses all bins in $\mathcal{O}(n \log^2 n)$ rounds, w.h.p

All that glitters is not gold: polarization amid poverty reduction in Ghana

Ghana is an exceptional case in the Sub-Saharan Africa landscape. Together with a handful of other countries, Ghana offers the opportunity to analyze the distributional changes in the past two decades, since four comparable household surveys are available. In addition, different from many other countries in the continent, Ghana's rapid growth translated into fast poverty reduction. A closer look at the distributional changes that occurred in the same period, however, suggests less optimism. The present paper develops an innovative methodology to analyze the distributional changes that occurred and their drivers, with a high degree of accuracy and granularity. Looking at the results from 1991 to 2012, the paper documents how the distributional changes hollowed out the middle of the Ghanaian household consumption distribution and increased the concentration of households around the highest and lowest deciles; there was a clear surge in polarization indeed. When looking at the drivers of polarization, household characteristics, educational attainment, and access to basic infrastructure all tended to increase over time the size of the upper and lower tails of the consumption distribution and, as a consequence, the degree of polarization

The non-smooth tale of Accumoli civic tower

In this paper, advanced numerical models are used to study the progressive damage of a historic building, namely the Palazzo of Podestà and the Civic Tower of Accumoli (central Italy). The dynamic behaviour of the structure is analyzed following important seismic events such as those that occurred in 2016-2017. Discontinuous and continuous approaches are used. In the formers, the masonry response is represented both with Discrete Element Method (DEM) and the Non-Smooth Contact Dynamic (NSCD) method; in the latter the masonry non linearity is replicated using the Concrete Damage Plasticity (CDP) model. The numerical results showed a good correspondence of all the approaches with the real damage suffered by the structure after the seismic sequence