Applied general equilibrium (AGE) models, which feature multiple countries, multiple industries, and input-output linkages across industries, have been the dominant tool for evaluating the impact of ...trade reforms since the 1980s. We review how these models are used to perform policy analysis and document their shortcomings in predicting the industry-level effects of past trade reforms. We argue that, to improve their performance, AGE models need to incorporate product-level data on bilateral trade relations by industry and better model how trade reforms lower bilateral trade costs. We use the least-traded-products methodology of
Kehoe et al. (2015)
to provide guidance on how improvements can be made. We provide further suggestions on how AGE models can incorporate recent advances in quantitative trade theory to improve their predictive ability and better quantify the gains from trade liberalization.
We study trade disruptions at different stages of development in a two‐country, three‐sector model of Spain and United Kingdom from 1850 to 2000. The impact of trade disruptions depends on trade ...openness and the productivity gap between countries. A trade collapse today (more openness, less gap) comparable to the Inter‐War Trade Collapse (IWTC) decreases the capital stock threefold (12% instead of 4%) and lifetime consumption fourfold (1.58% instead of 0.37%). Capital accumulation amplifies the cost of trade disruptions. The IWTC promoted Spanish industrialization, while the opposite would be true today.
We show that a trade model with an exogenous set of heterogeneous firms with fixed operating costs has the same aggregate outcomes as a span-of-control model. Fixed costs in the heterogeneous-firm ...model are entrepreneurs’ forgone wages in the span-of-control model.
•The span-of-control model and the Chaney (2008) model are equivalent.•Operating fixed cost acts as forgone wage of entrepreneurs.•Chaney (2008) model useful to study link between liberalization and distribution.
Simulations are routinely used to study the process of carbon dioxide (CO2) sequestration in saline aquifers. In this paper, we describe the modeling and simulation of the ...dissolution-diffusion-convection process based on a total velocity splitting formulation for a variable-density incompressible single-phase model. A second-order accurate sequential algorithm, implemented within a block-structured adaptive mesh refinement (AMR) framework, is used to perform high-resolution studies of the process. We study both the short-term and long-term behaviors of the process. It is found that the onset time of convection follows closely the prediction of linear stability analysis. In addition, the CO2 flux at the top boundary, which gives the rate at which CO2 gas dissolves into a negatively buoyant aqueous phase, will reach a stabilized state at the space and time scales we are interested in. This flux is found to be proportional to permeability, and independent of porosity and effective diffusivity, indicative of a convection-dominated flow. A 3D simulation further shows that the added degrees of freedom shorten the onset time and increase the magnitude of the stabilized CO2 flux by about 25%. Finally, our results are found to be comparable to results obtained from TOUGH2-MP.
Warming experiments are increasingly relied on to estimate plant responses to global climate change. For experiments to provide meaningful predictions of future responses, they should reflect the ...empirical record of responses to temperature variability and recent warming, including advances in the timing of flowering and leafing. We compared phenology (the timing of recurring life history events) in observational studies and warming experiments spanning four continents and 1,634 plant species using a common measure of temperature sensitivity (change in days per degree Celsius). We show that warming experiments underpredict advances in the timing of flowering and leafing by 8.5-fold and 4.0-fold, respectively, compared with long-term observations. For species that were common to both study types, the experimental results did not match the observational data in sign or magnitude. The observational data also showed that species that flower earliest in the spring have the highest temperature sensitivities, but this trend was not reflected in the experimental data. These significant mismatches seem to be unrelated to the study length or to the degree of manipulated warming in experiments. The discrepancy between experiments and observations, however, could arise from complex interactions among multiple drivers in the observational data, or it could arise from remediable artefacts in the experiments that result in lower irradiance and drier soils, thus dampening the phenological responses to manipulated warming. Our results introduce uncertainty into ecosystem models that are informed solely by experiments and suggest that responses to climate change that are predicted using such models should be re-evaluated.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Total factor productivity (TFP) growth in Canada between 2002 and 2014 has been only 0.16% per year. This figure is substantially smaller than that of the United States, or that of Canada in the ...past. We perform multiple counterfactual exercises to show that this small TFP growth cannot be accounted for by several compositional effects or mismeasurements of factors of production. We identify two key sectors (mostly Mining and to a lesser extent Manufacturing) that drive all of the TFP growth difference with the United States. Despite the lack of TFP growth, Canada has experienced sustained income growth due to a prolonged period of appreciation of the terms of trade (while US terms of trade have deteriorated), making real income in the two countries grow at similar rates.
L’augmentation de la productivité totale des facteurs (PTF) au Canada entre 2002 et 2014 n’a été que de 0,16 % par année. Ce chiffre est sensiblement inférieur à celui des États-Unis ou à ceux du Canada auparavant. Nous effectuons plusieurs exercices contrefactuels pour montrer que cette moindre croissance de la PTF ne peut pas être expliquée par plusieurs effets de composition ou par une erreur dans la mesure les facteurs de production. Nous identifions deux secteurs clés (principalement l’industrie minière et, de moindre importance, le secteur manufacturier) qui déterminent toute la différence entre l’augmentation de la PTF avec les États-Unis. Malgré l’absence de croissance de la PTF, le Canada a connu une croissance soutenue des revenus en raison d’une longue période d’appréciation des termes de l’échange (alors que les termes de l’échange se sont détériorés), ce qui fait augmenter le revenu réel des deux pays à des taux similaires. détériorés), ce qui fait augmenter le revenu réel des deux pays à des taux similaires.
We measure gains from trade in multisector economies with nonhomothetic preferences where changes in trade costs generate reallocation of expenditure across sectors. We show how to measure the trade ...elasticity and how it relates to welfare. In this environment, the trade elasticity now varies both across countries and with levels of trade costs. In an application, we find that the trade elasticity varies substantially across countries and that the gains from moving from autarky to observed trade are on average between 24% and 28% greater than in a model where the trade elasticity is constant.
In the ovine reproductive management, a thorough breeding soundness evaluation including specific inspection of the male genital tract represents a valuable tool for assessing the reproductive ...potential of a selected subject and for diagnosing genital disorders. During examination, accurate inspection on penis and prepuce is necessary, since conditions affecting these structures may hamper regular coitus. Records from 1270 males undergoing breeding soundness evaluation (n = 1232) or admitted for genital disorders to the Section of Obstetrics and Gynaecology (n = 38) of the Department of Veterinary Medicine, were collected, and lesions of penis and prepuce were therefore classified. The data collected revealed that 47/1270 rams examined presented lesions of the penis and prepuce. The most frequent condition was urolithiasis accounting for over 2% of the cases, followed by lack of the urethral process (0.39% incidence), lack of the glans penis and hypospadias (0.23% cases). Moreover, most of the conditions (40%) were observed in animals less than 2 years old, suggesting the importance of a careful breeding soundness evaluation in animals at young age.
We measure the gains from a trade cost reduction in a model with dynamic accumulation of factors. We show that the tight link between import intensity and gains from trade that exists in static ...models breaks down along transition paths in dynamic models. When trade costs are reduced, the need to accumulate factors temporarily shifts spending from consumption to investment. Import intensity may rise or fall along the transition path, depending on the relative import intensity of consumption and investment. Calibrating the model to the US economy, we find that investment is more import intensive than consumption, so that import intensity is falling along the transition path even as consumption is rising. Therefore, while higher import intensity is associated with higher consumption when comparing steady states (as in static models), it is associated with lower consumption along a given transition path. We also consider the case of endogenous firm creation as another form of investment and factor accumulation, and again find a negative relationship between consumption and import intensity along the transition path.
Long-term intensive sensorimotor training alters functional representation of the motor and sensory system and might even result in structural changes. However, there is not much knowledge about how ...previous training impacts learning transfer and functional representation. We tested 14 amateur pianists and 15 musically naïve participants in a short-term finger sequence training procedure, differing considerably from piano playing and measured associated functional representation with functional magnetic resonance imaging. The conditions consisted of encoding a finger sequence indicated by hand symbols (“sequence encoding”) and subsequently replaying the sequence from memory, both with and without auditory feedback (“sequence retrieval”).
Piano players activated motor areas and the mirror neuron system more strongly than musically naïve participants during encoding. When retrieving the sequence, musically naïve participants showed higher activation in similar brain areas. Thus, retrieval activations of naïve participants were comparable to encoding activations of piano players, who during retrieval performed the sequences more accurately despite lower motor activations. Interestingly, both groups showed primary auditory activation even during sequence retrieval without auditory feedback, supporting previous reports about coactivation of the auditory cortex after learned association with motor performance. When playing with auditory feedback, only pianists lateralized to the left auditory cortex.
During encoding activation in left primary somatosensory cortex in the height of the finger representations had a predictive value for increased motor performance later on (error rates). Contrarily, decreased performance was associated with increased visual cortex activation during encoding.
Our study extends previous reports about training transfer of motor knowledge resulting in superior training effects in musicians. Performance increase went along with activity in motor areas and the mirror neuron network during pattern encoding.
► Comparison of fMRI-maps during motor transfer in pianists and naive healthy subjects. ► Pianists differ from naïve subjects in motor performance for the new task. ► Pianists recruit motor areas and the mirror neural system already during encoding. ► Naive subjects increase motor recruitment during retrieval but perform worse.
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