Norms as Emergent Properties of Adaptive Learning: The Case of Economic Routines

Strategic interaction among autonomous decision-makers is usually modelled in economics in game-theoretic terms or within the framework of General Equilibrium. Game-theoretic and General Equilibrium models deal almost exclusively with the existence of equilibria and do not analyse the processes which might lead to them. Even when existence proofs can be given, two questions are still open. The first concerns the possibility of multiple equilibria, which game theory has shown to be the case even in very simple models and which makes the outcome of interaction unpredictable. The second relates to the computability and complexity of the decision procedures which agents should adopt and questions the possibility of reaching an equilibrium by means of an algorithmically implementable strategy. Some theorems have recently proved that in many economically relevant problems equilibria are not computable. A different approach to the problem of strategic interaction is a "constructivist" one. Such a perspective, instead of being based upon an axiomatic view of human behaviour grounded on the principle of optimisation, focuses on algorithmically implementable "satisfycing" decision procedures. Once the axiomatic approach has been abandoned, decision procedures cannot be deduced from rationality assumptions, but must be the evolving outcome of a process of learning and adaptation to the particular environment in which the decision must be made. This paper considers one of the most recently proposed adaptive learning models: Genetic Programming and applies it to one the mostly studied and still controversial economic interaction environment, that of oligopolistic markets. Genetic Programming evolves decision procedures, represented by elements in the space of functions, balancing the exploitation of knowledge previously obtained with the search of more productive procedures. The results obtained are consistent with the evidence from the observation of the behaviour of real economic agents

Proteobacteria Overgrowth and Butyrate-Producing Taxa Depletion in the Gut Microbiota of Glycogen Storage Disease Type 1 Patients

A life-long dietary intervention can affect the substrates' availability for gut fermentation in metabolic diseases such as the glycogen-storage diseases (GSD). Besides drug consumption, the main treatment of types GSD-Ia and Ib to prevent metabolic complications is a specific diet with definite nutrient intakes. In order to evaluate how deeply this dietary treatment affects gut bacteria, we compared the gut microbiota of nine GSD-I subjects and 12 healthy controls (HC) through 16S rRNA gene sequencing; we assessed their dietary intake and nutrients, their microbial short chain fatty acids (SCFAs) via gas chromatography and their hematic values. Both alpha-diversity and phylogenetic analysis revealed a significant biodiversity reduction in the GSD group compared to the HC group, and highlighted profound differences of their gut microbiota. GSD subjects were characterized by an increase in the relative abundance of Enterobacteriaceae and Veillonellaceae families, while the beneficial genera Faecalibacterium and Oscillospira were significantly reduced. SCFA quantification revealed a significant increase of fecal acetate and propionate in GSD subjects, but with a beneficial role probably reduced due to unbalanced bacterial interactions; nutritional values correlated to bacterial genera were significantly different between experimental groups, with nearly opposite cohort trends

OLIMPIC : a 12-month study on the criteria driving retreatment with ranibizumab in patients with visual impairment due to myopic choroidal neovascularization

Purpose: To evaluate criteria driving retreatment with ranibizumab in Italian patients with myopic choroidal neovascularization (mCNV). Methods: OLIMPIC was a 12-month, phase IIIb, open-label study. Patients with active mCNV were treated with ranibizumab 0.5 mg according to the European label. The study assessed local criteria in Italy driving retreatment decisions with ranibizumab; and the efficacy, safety, and tolerability of ranibizumab. Results: The mean (standard deviation [SD]) age of treated patients (N = 200) was 61.8 (12.7) years; range 22\u201385 years. The multivariate regression model indicated that presence of active leakage (odds ratio [OR] 95% confidence interval [CI]: 11.30 [1.03\u2013124.14]), presence of intraretinal fluid (OR [95%CI]: 28.21 [1.55\u2013513.73]), and an improvement in best-corrected visual acuity (BCVA) from baseline < 10 letters (OR [95%CI]: 17.60 [1.39\u2013222.75]) were the factors with the greatest effect on retreatment with ranibizumab. The mean (SD) BCVA gain from baseline to month 12 was 8.4 (12.8) letters (P < 0.0001). The mean (SD) number of injections was 2.41 (1.53); range 1\u20139. Ocular and non-ocular adverse events were reported in 41 (20.5%) and 30 (15.0%) patients, respectively. Conclusions: Individualized treatment with ranibizumab was effective in improving BCVA in patients with mCNV over 12 months. Both anatomical and functional variables had significant effects on causing retreatment. There were no new safety findings. Trial registration: www.ClinicalTrials.Gov (NCT No: NCT02034006)

A method for the assessment of time-varying brain shift during navigated epilepsy surgery

Image guidance is widely used in neurosurgery. Tracking systems (neuronavigators) allow registering the preoperative image space to the surgical space. The localization accuracy is influenced by technical and clinical factors, such as brain shift. This paper aims at providing quantitative measure of the time-varying brain shift during open epilepsy surgery, and at measuring the pattern of brain deformation with respect to three potentially meaningful parameters: craniotomy area, craniotomy orientation and gravity vector direction in the images reference frame

Does labour regulation affect technical and allocative efficiency? Evidence from the banking industry

In light of the ongoing restructuring of the European banking industry and the challenging macroeconomic environment, banks have increased their efforts to reduce operating costs. Yet, the institutional features that affect banks’ ability to adjust costs and in particular personnel expenses, which comprise a significant part of banks’ non-interest cost structure, have not been adequately studied. This paper investigates the effect of labour market institutions and regulations on bank performance in 15 European countries over the period 2005-2010, using the Fraser index for labour regulation and its disaggregated sub-components. We propose a novel methodology to measure performance, based on the seminal work of Kumbhakar and Tsionas (2005), which allows the estimation of technical and allocative efficiency and the examination of the effect of labour market regulations in a single stage. Results indicate the existence of a positive relationship between the liberalization of EU labour markets and allocative efficiency, while the effect on technical efficiency appears to be negative, although not statistically significant. When looking at the disaggregated components of the labour index, we further confirm that different forces are at play

Poaching and firm-sponsored training: first clean evidence

A series of seminal theoretical papers argues that poaching of employees may hamper company-sponsored general training. However, the extent of poaching, its determinants and consequences, remains an open empirical question. We provide a novel empirical identification strategy for poaching and investigate its causes and consequences. We find that only a small number of training firms in Germany are poaching victims. Firms are more likely to poach employees during an economic downturn. Training firms respond to poaching by lowering the share of new apprentice intakes in the following years