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Essays on Economic and Social Complexity
Get PDFThe multidisciplinary approach to problem solving involves drawing appropriately from different viewpoints to redefine problems outside of normal boundaries and reach solutions based on a new understanding of complex situations. Social and economics science have always borrowed and embraced tools and instruments from mathematics and physics to develop their theories. Historically a real multidisciplinary methodology to economic and social issues has been neglected by the academic researchers due to a widespread gap in their formal approach. Recently a new interdisciplinary framework has been developed connecting together social and economics theories with the complex systems analysis; this approach reveals new conceptual prospectives and methodologies thanks to its multiple-level viewpoint, which are able to disclose novel challenges and problems. This thesis collects three different multidisciplinary approaches to social and economic behaviors formalized with the complex systems tools. Chapter 2: We introduce a statistical agent based model to describe the phenomenon of drug abuse and its dynamical evolution at the individual and global level. The agents are heterogeneous with respect to their intrinsic inclination to drugs, to their budget attitude and social environment. The various levels of drug use were inspired by the professional description of the phenomenon and this permits a direct comparison with all available data. We show that certain elements have a great importance to start the use of drugs, for example the rare events in the personal experiences which permit to overcome the barrier of drug use occasionally. The analysis of how the system reacts to perturbations is very important to understand its key elements and it provides strategies for effective policy making. The present model represents the first step of a realistic description of this phenomenon and can be easily generalized in various directions. Chapter 3: We characterize the statistical law according to which Italian primary school-size distributes. We find that the schoolsize can be approximated by a log-normal distribution, with a fat lower tail that collects a large number of very small schools. The upper tail of the school-size distribution decreases exponentially and the growth rates are distributed with a Laplace PDF. These distributions are similar to those observed for firms and are consistent with a Bose-Einstein preferential attachment process. The body of the distribution features a bimodal shape suggesting some source of heterogeneity in the school organization that we uncover by an indepth analysis of the relation between schools-size and citysize. We propose a novel cluster methodology and a new spatial interaction approach among schools which outline the variety of policies implemented in Italy. Different regional policies are also discussed shedding lights on the relation between policy and geographical features. Chapter 4: By analyzing the distribution of revenues across the production sectors of quoted firms we suggest a novel dimension that drives the firms diversification process at country level. Data show a non trivial macro regional clustering of the diversification process, which underlines the relevance of geopolitical environments in determining the microscopic dynamics of economic entities. These findings demonstrate the possibility of singling out in complex ecosystems those microfeatures that emerge at macro-levels, which could be of particular relevance for decision-makers in selecting the appropriate parameters to be acted upon in order to achieve desirable results. The understanding of this micro-macro information exchange is further deepened through the introduction of a simplified dynamic model
The Italian primary school-size distribution and the city-size: A complex nexus
Get PDFWe characterize the statistical law according to which Italian primary school-size distributes. We find that the school-size can be approximated by a log-normal distribution, with a fat lower tail that collects a large number of very small schools. The upper tail of the school-size distribution decreases exponentially and the growth rates are distributed with a Laplace PDF. These distributions are similar to those observed for firms and are consistent with a Bose-Einstein preferential attachment process. The body of the distribution features a bimodal shape suggesting some source of heterogeneity in the school organization that we uncover by an in-depth analysis of the relation between schools-size and city-size. We propose a novel cluster methodology and a new spatial interaction approach among schools which outline the variety of policies implemented in Italy. Different regional policies are also discussed shedding lights on the relation between policy and geographical features. © 2014 Macmillan Publishers Limited. All rights reserved
Oliver Ayers, Review of 'The Making of Black Detroit in the Age of Henry Ford', by Beth Tompkins Bates
Get PDFCaravaggio to Canaletto: The Glory of Italian Baroque and Rococo Painting
Get PDFOnline review of an exhibition held at the Szépmûvészeti Múseum in Budapest offering a comprehensive overview of Italian painting in the seventeenth and eighteenth centuries. With 142 paintings by 101 artists and multiple loans from museums across the globe, the star factor was undoubtedly the nine Caravaggios. These included 'Salomé with the Head of Saint John the Baptist' (c. 1608) from London and 'Boy with a Basket of Fruit' (c. 1593) from Rome. Throughout the winter, 'Caravaggio to Canaletto' posters stretched across Europe, from the streets of Vienna to the walls of the London underground. Everywhere, it seemed, daily newspapers and tourist advertisements were touting the exhibition as ‘the Budapest Winter offer’ or the essential ‘treat for art lovers’
Urinary ATP and visualization of intracellular bacteria: a superior diagnostic marker for recurrent UTI in renal transplant recipients?
Get PDFRenal transplant recipients (RTR) are highly susceptible to urinary tract infections (UTIs) with over 50% of patients having at least one UTI within the first year. Yet it is generally acknowledged that there is considerable insensitivity and inaccuracy in routine urinalysis when screening for UTIs. Thus a large number of transplant patients with genuine urine infections may go undiagnosed and develop chronic recalcitrant infections, which can be associated with graft loss and morbidity. Given a recent study demonstrating ATP is released by urothelial cells in response to bacteria exposure, possibly acting at metabotropic P2Y receptors mediating a proinflammatory response, we have investigated alternative, and possibly more appropriate, urinalysis techniques in a cohort of RTRs. Mid-stream urine (MSU) samples were collected from 53 outpatient RTRs. Conventional leukocyte esterase and nitrite dipstick tests, and microscopic pyuria counts (in 1 μl), ATP concentration measurements, and identification of intracellular bacteria in shed urothelial cells, were performed on fresh unspun samples and compared to 'gold-standard' bacterial culture results. Of the 53 RTRs, 22% were deemed to have a UTI by 'gold-standard' conventional bacteria culture, whereas 87%, 8% and 4% showed evidence of UTIs according to leukocyte esterase dipstick, nitrite dipstick, and a combination of both dipsticks, respectively. Intracellular bacteria were visualized in shed urothelial cells of 44% of RTRs, however only 1 of the 23 RTRs (44%) was deemed to have a UTI by conventional bacteria culture. A significant association of the 'gold-standard' test with urinary ATP concentration combined with visualization of intracellular bacteria in shed urothelial cells was determined using the Fisher's exact test. It is apparent that standard bedside tests for UTIs give variable results and that seemingly quiescent bacteria in urothelial cells are very common in RTRs and may represent a focus of subclinical infection. Furthermore, our results suggest urinary ATP concentration combined with detection of intracellular bacteria in shed urinary epithelial cells may be a sensitive means by which to detect 'occult' infection in RTRs
Reconstructing scientific theory change by means of frames
Get PDFThis paper has two aims. The first is to show the usefulness and intuitiveness of frame theory in reconstructing scientific classification systems. The second is to employ such reconstructions in order to make headway in the scientific realism debate and, more specifically, in the question concerning scientific theory change. Two case studies are utilised with the second aim in mind. The first concerns the transition from the phlogiston theory to the oxygen theory of combustion, while the second concerns the transition from the caloric theory to the kinetic theory of heat. Frame-theoretic reconstructions of these theories reveal substantial structural continuities across theory change. This outcome supports a structural realist view of science, according to which successful scientific theories reveal only structural features of the unobservable world
Company Reputations and Disclosures
No full textTraditional financial reporting research focuses on information to the stock market. With increasing emphasis on environmental and social issues in accounting and finance research, though, issues of company reputation and disclosures have become significant. By implication, reputation and disclosures are related, but only two studies have examined the link. This paper reviews academic discourse of recent years related to reputation and disclosures, reaching a pessimistic conclusion that companies are largely indifferent to public disclosures and that there is wide-spread non-compliance with required disclosure standards by companies and their auditors. Instead, companies use back-channel private disclosures to maintain and enhance their reputations with perceived key constituents. The paper examines theories that have driven previous research and can be used for future research, and presents research questions for ongoing accounting and finance research
The Dynamics of Norms and Convention under Random Matching
Get PDFRestricting the analysis to general 2 × 2 coordination games, this article shows how under certain conditions, it is highly likely that individuals coordinate on a (pay-off) efficient though risk inferior convention. This contrasts with other equilibrium refinement criteria, such as risk dominance or stochastic stability. Here it is assumed that players are situated on a toroidal regular lattice, interact only locally and, in each period, imitate the last period’s most successful player in their neighborhood. If the set of observable players by an individual and the set that he interacts with are both identical and small, pay-off dominance plays the major role in defining the long-term convention. As the latter set of players increases, a risk dominant but pay-off inferior convention becomes more likely. The model also shows that the interaction of two player types in a non-symmetric game potentially leads to non-egalitarian conventions
