148,863 research outputs found
Disturbances, robustness and adaptation in forest commons: comparative insights from two cases in the Southeastern Alps
Exposure to disturbances of different nature and scale can represent a threat for the survival of rural communities but also a stimulus to adjustment. Disturbance, robustness and adaptation are here examined through the lens of Forest Commons, as a typical institution, developed by communities in the southeastern Alps since several centuries. The paper relies on Commons' theory and further developments and carries out a historically-embedded analysis of disturbances, robustness and adaptation in Forest Commons of Slovenia and Veneto (Italy). Data have been drawn from multiple sources, following an approach based on an area scale and later on case-studies. The analysis focuses on evidence of Forest Commons\ub4 reactions to disturbances induced by political changes and State actions. Ostrom's design principles are used to test robustness of eight selected cases and identification of their adaptation patterns. The paper concludes by confirming Forest Commons as robust and adaptive socio-ecological systems and thus useful in Community Forestry conceptualisation. However, thanks to its cross-border analysis, it also points out future research needs for their better understanding
Complexity and monetary policy : [Version August 10, 2012]
The complexity resulting from intertwined uncertainties regarding model misspecification and mismeasurement of the state of the economy defines the monetary policy landscape. Using the euro area as laboratory this paper explores the design of robust policy guides aiming to maintain stability in the economy while recognizing this complexity. We document substantial output gap mismeasurement and make use of a new model data base to capture the evolution of model specification. A simple interest rate rule is employed to interpret ECB policy since 1999. An evaluation of alternative policy rules across 11 models of the euro area confirms the fragility of policy analysis optimized for any specific model and shows the merits of model averaging in policy design. Interestingly, a simple difference rule with the same coefficients on inflation and output growth as the one used to interpret ECB policy is quite robust as long as it responds to current outcomes of these variables
Heterogeneous Employment Effects of Job Search Programmes: A Machine Learning Approach
We systematically investigate the effect heterogeneity of job search
programmes for unemployed workers. To investigate possibly heterogeneous
employment effects, we combine non-experimental causal empirical models with
Lasso-type estimators. The empirical analyses are based on rich administrative
data from Swiss social security records. We find considerable heterogeneities
only during the first six months after the start of training. Consistent with
previous results of the literature, unemployed persons with fewer employment
opportunities profit more from participating in these programmes. Furthermore,
we also document heterogeneous employment effects by residence status. Finally,
we show the potential of easy-to-implement programme participation rules for
improving average employment effects of these active labour market programmes
Complexity and monetary policy
The complexity resulting from intertwined uncertainties regarding model misspecification and mismeasurement of the state of the economy defines the monetary policy landscape. Using the euro area as laboratory this paper explores the design of robust policy guides aiming to maintain stability in the economy while recognizing this complexity. We document substantial output gap mismeasurement and make use of a new model data base to capture the evolution of model specification. A simple interest rate rule is employed to interpret ECB policy since 1999. An evaluation of alternative policy rules across 11 models of the euro area confirms the fragility of policy analysis optimized for any specific model and shows the merits of model averaging in policy design. Interestingly, a simple difference rule with the same coefficients on inflation and output growth as the one used to interpret ECB policy is quite robust as long as it responds to current outcomes of these variables
ANCHOR: logically-centralized security for Software-Defined Networks
While the centralization of SDN brought advantages such as a faster pace of
innovation, it also disrupted some of the natural defenses of traditional
architectures against different threats. The literature on SDN has mostly been
concerned with the functional side, despite some specific works concerning
non-functional properties like 'security' or 'dependability'. Though addressing
the latter in an ad-hoc, piecemeal way, may work, it will most likely lead to
efficiency and effectiveness problems. We claim that the enforcement of
non-functional properties as a pillar of SDN robustness calls for a systemic
approach. As a general concept, we propose ANCHOR, a subsystem architecture
that promotes the logical centralization of non-functional properties. To show
the effectiveness of the concept, we focus on 'security' in this paper: we
identify the current security gaps in SDNs and we populate the architecture
middleware with the appropriate security mechanisms, in a global and consistent
manner. Essential security mechanisms provided by anchor include reliable
entropy and resilient pseudo-random generators, and protocols for secure
registration and association of SDN devices. We claim and justify in the paper
that centralizing such mechanisms is key for their effectiveness, by allowing
us to: define and enforce global policies for those properties; reduce the
complexity of controllers and forwarding devices; ensure higher levels of
robustness for critical services; foster interoperability of the non-functional
property enforcement mechanisms; and promote the security and resilience of the
architecture itself. We discuss design and implementation aspects, and we prove
and evaluate our algorithms and mechanisms, including the formalisation of the
main protocols and the verification of their core security properties using the
Tamarin prover.Comment: 42 pages, 4 figures, 3 tables, 5 algorithms, 139 reference
Insurance policies for monetary policy in the Euro area
In this paper, we examine the cost of insurance against model uncertainty for the Euro area considering four alternative reference models, all of which are used for policy-analysis at the ECB.We find that maximal insurance across this model range in terms of aMinimax policy comes at moderate costs in terms of lower expected performance. We extract priors that would rationalize the Minimax policy from a Bayesian perspective. These priors indicate that full insurance is strongly oriented towards the model with highest baseline losses. Furthermore, this policy is not as tolerant towards small perturbations of policy parameters as the Bayesian policy rule. We propose to strike a compromise and use preferences for policy design that allow for intermediate degrees of ambiguity-aversion.These preferences allow the specification of priors but also give extra weight to the worst uncertain outcomes in a given context. JEL Klassifikation: E52, E58, E61
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