4,130 research outputs found
How OECD policies affected Latin America in the 1980s
The authors assess the effects of OECD monetary and fiscal policies on Latin America by means of simulation studies using the LBS/NIESR Global Econometric Model and a new empirical model of Latin America. The Latin American model pays special attention to the supply-side determination of natural rate of output and to the effects of asset accumulation. The Latin American model and its properties are presented by both empirical simulations and by means of a simple analytical representation. This model of Latin America is used in conjunction with the Global Econometric Model to study the macroeconomic interactions between Latin America and the rest of the world. The assumption in policy simulations is that G-3 exchange rates are forward-looking while Latin America pegs its currency to the U.S. dollar. It is postulated that Latin American fiscal policy adjustments target a baseline current account balance, in the face of external shocks. The simulation results reflect a number of important international links, which can be quantified as multiplier properties of the linked system of models. A permanent 5 percent contraction in the U.S. money supply induces a contraction of about the same order in Latin American GDP and capital stock. This is caused by higher U.S. interest rates and diminished Latin American competitiveness in third markets, reinforcing the fall in U.S. demand. Similarly, a combined monetary contraction in G-3 countries on a permanent footing - a contraction like the one in 1978-80 (U.S., 5.2 percent, German, 11.9 percent, and Japanese, 1.7 percent) hurts Latin America. Latin American GDP remains depressed by 4 percent and capital stock by 5 percent even after 10 years. The effects of negative income and interest rates emanating from G-3 countries are mutually reinforcing. U.S. fiscal expansion equal to 1 percent of baseline GDP, sustained over five years, transmits negatively to Latin America, where GDP falls 0.6 percent in the short run and remains depressed by 0.3 percent even after 10 years. The negative effects of higher interest rates and diminished competitiveness dominate the positive effects (which are short-lived) of expanded U.S. demand for Latin American exports. Similarly, G-3 fiscal spending shocks, which aregradually built up over five years, then reversed the next two years, have a mild negative effect on Latin American GDP. The G-3 fiscal shocks administered were set to their actual magnitudes relative to baseline GDP, as observed in 1980-85 (U.S. expansion of 3.5 percent but contraction in German and Japanese spending of 4.4 percent and 3.5 percent, respectively). Latin American GDP is lower than baseline GDP by 0.5 percent when the shocks peak at the end of five years, but continues to remain depressed 0.3 percent by the end of 10 years. The simulated effects of G-3 monetary and fiscal policies, with the shocks constructed to reflect their actual sizes in the early 1980s, suggest that Latin America's adjustment problems in that period cannot be attributed to G-3 fiscal imbalances that arose because of failures of G-3 fiscal policy coordination. But concerted G-3 monetary contraction in response to the second oil shock imposed heavy costs on Latin America; without it, Latin American GDP would have been 5 percent higher in the 1980s.Fiscal&Monetary Policy,Macroeconomic Management,Economic Theory&Research,Environmental Economics&Policies,Economic Stabilization
Unique Effects of Setting Goals on Behavior Change: Systematic Review and Meta-Analysis
Objective: Goal setting is a common feature of behavior change interventions, but it is unclear when goal setting is optimally effective. The aims of this systematic review and meta-analysis were to evaluate: (a) the unique effects of goal setting on behavior change, and (b) under what circumstances and for whom goal setting works best. Method: Four databases were searched for articles that assessed the unique effects of goal setting on behavior change using randomized controlled trials. One-hundred and 41 papers were identified from which 384 effect sizes (N = 16,523) were extracted and analyzed. A moderator analysis of sample characteristics, intervention characteristics, inclusion of other behavior change techniques, study design and delivery, quality of study, outcome measures, and behavior targeted was conducted. Results: A random effects model indicated a small positive unique effect of goal setting across a range of behaviors, d = .34 (CI [.28, .41]). Moderator analyses indicated that goal setting was particularly effective if the goal was: (a) difficult, (b) set publicly, and (c) was a group goal. There was weaker evidence that goal setting was more effective when paired with external monitoring of the behavior/outcome by others without feedback and delivered face-to-face. Conclusions: Goal setting is an effective behavior change technique that has the potential to be considered a fundamental component of successful interventions. The present review adds novel insights into the means by which goal setting might be augmented to maximize behavior change and sets the agenda for future programs of research
Regulatory Structures and their Impact on the Sustainability Performance of Public Transport in World Cities
This paper describes a new measure of the sustainability performance of public transport in 88 world cities adopting 15 indicators including Environmental, Social, Economic and System Effectiveness sustainability. Sustainability performance is then explored for cities with only “Public” operations or others with some degree of commercial operation (“Non-Public”) Results show no significant difference in aggregate total sustainability indicator scores between world cities with “Public”/“Non-Public” operations. However Social Sustainability indicators are significantly different with “Public” operations having better Social Sustainability performance than “Non-Public”. For individual component indicators, three of the four Social Sustainability component indicators have average normalised scores suggesting statistically significant differences between “Public” and “Non-Public” city scores with “Public” cities performing better than “Non-Public”. The indicators and their relative advantage to “Public” cities being Trip distance (24%), Affordability (34%) and PT related deaths (29%). However results also show that operating costs per passenger km and cost recovery are higher in “Non-Public” cities suggesting higher elements of Economic Sustainability in “Non-Public” based Public Transport cities The paper concludes with a summary and discussion of the results including implications for regulatory practices and areas for future research.Institute of Transport and Logistics Studies. Faculty of Economics and Business. The University of Sydne
Evaluation of the incremental cost to the National Health Service of prescribing analogue insulin
Introduction Insulin analogues have become increasingly popular despite their greater cost compared with human insulin. The aim of this study was to calculate the incremental cost to the National Health Service (NHS) of prescribing analogue insulin preparations instead of their human insulin alternatives. Methods Open-source data from the four UK prescription pricing agencies from 2000 to 2009 were analysed. Cost was adjusted for inflation and reported in UK pounds at 2010 prices. Results Over the 10-year period, the NHS spent a total of £2732 million on insulin. The total annual cost increased from £156 million to £359 million, an increase of 130%. The annual cost of analogue insulin increased from £18.2 million (12% of total insulin cost) to £305 million (85% of total insulin cost), whereas the cost of human insulin decreased from £131 million (84% of total insulin cost) to £51 million (14% of total insulin cost). If it is assumed that all patients using insulin analogues could have received human insulin instead, the overall incremental cost of analogue insulin was £625 million. Conclusion Given the high marginal cost of analogue insulin, adherence to prescribing guidelines recommending the preferential use of human insulin would have resulted in considerable financial savings over the period
Magnetic field generation in finite beam plasma system
For finite systems boundaries can introduce remarkable novel features. A well
known example is the Casimir effect [1, 2] that is observed in quantum
electrodynamic systems. In classical systems too novel effects associated with
finite boundaries have been observed, for example the surface plasmon mode [3]
that appears when the plasma has a finite extension. In this work a novel
instability associated with the finite transverse size of a beam owing through
a plasma system has been shown to exist. This instability leads to distinct
characteristic features of the associated magnetic field that gets generated.
For example, in contrast to the well known unstable Weibel mode of a beam
plasma system which generates magnetic field at the skin depth scale, this
instability generates magnetic field at the scales length of the transverse
beam dimension [4]. The existence of this new instability is demonstrated by
analytical arguments and by simulations conducted with the help of a variety of
Particle - In - Cell (PIC) codes (e.g. OSIRIS, EPOCH, PICPSI). Two fluid
simulations have also been conducted which confirm the observations.
Furthermore, laboratory experiments on laser plasma system also provides
evidence of such an instability mechanism at work
Performance Limits of Stochastic Sub-Gradient Learning, Part II: Multi-Agent Case
The analysis in Part I revealed interesting properties for subgradient
learning algorithms in the context of stochastic optimization when gradient
noise is present. These algorithms are used when the risk functions are
non-smooth and involve non-differentiable components. They have been long
recognized as being slow converging methods. However, it was revealed in Part I
that the rate of convergence becomes linear for stochastic optimization
problems, with the error iterate converging at an exponential rate
to within an neighborhood of the optimizer, for some and small step-size . The conclusion was established under weaker
assumptions than the prior literature and, moreover, several important problems
(such as LASSO, SVM, and Total Variation) were shown to satisfy these weaker
assumptions automatically (but not the previously used conditions from the
literature). These results revealed that sub-gradient learning methods have
more favorable behavior than originally thought when used to enable continuous
adaptation and learning. The results of Part I were exclusive to single-agent
adaptation. The purpose of the current Part II is to examine the implications
of these discoveries when a collection of networked agents employs subgradient
learning as their cooperative mechanism. The analysis will show that, despite
the coupled dynamics that arises in a networked scenario, the agents are still
able to attain linear convergence in the stochastic case; they are also able to
reach agreement within of the optimizer
Solar wind collisional heating
To properly describe heating in weakly collisional turbulent plasmas such as
the solar wind, inter-particle collisions should be taken into account.
Collisions can convert ordered energy into heat by means of irreversible
relaxation towards the thermal equilibrium. Recently, Pezzi et al. (Phys. Rev.
Lett., vol. 116, 2016, p. 145001) showed that the plasma collisionality is
enhanced by the presence of fine structures in velocity space. Here, the
analysis is extended by directly comparing the effects of the fully nonlinear
Landau operator and a linearized Landau operator. By focusing on the relaxation
towards the equilibrium of an out of equilibrium distribution function in a
homogeneous force-free plasma, here it is pointed out that it is significant to
retain nonlinearities in the collisional operator to quantify the importance of
collisional effects. Although the presence of several characteristic times
associated with the dissipation of different phase space structures is
recovered in both the cases of the nonlinear and the linearized operators, the
influence of these times is different in the two cases. In the linearized
operator case, the recovered characteristic times are systematically larger
than in the fully nonlinear operator case, this suggesting that fine velocity
structures are dissipated slower if nonlinearities are neglected in the
collisional operator
Locus model for space-time fabric and quantum indeterminacies
A simple locus model for the space-time fabric is presented and is compared
with quantum foam and random walk models. The induced indeterminacies in
momentum are calculated and it is shown that these space-time fabric
indeterminacies are, in most cases, negligible compared with the quantum
mechanical indeterminacies. This result restricts the possibilities of an
experimental observation of the space-time fabric
Some Remarks about the Complexity of Epidemics Management
Recent outbreaks of Ebola, H1N1 and other infectious diseases have shown that
the assumptions underlying the established theory of epidemics management are
too idealistic. For an improvement of procedures and organizations involved in
fighting epidemics, extended models of epidemics management are required. The
necessary extensions consist in a representation of the management loop and the
potential frictions influencing the loop. The effects of the non-deterministic
frictions can be taken into account by including the measures of robustness and
risk in the assessment of management options. Thus, besides of the increased
structural complexity resulting from the model extensions, the computational
complexity of the task of epidemics management - interpreted as an optimization
problem - is increased as well. This is a serious obstacle for analyzing the
model and may require an additional pre-processing enabling a simplification of
the analysis process. The paper closes with an outlook discussing some
forthcoming problems
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