37 research outputs found
The Costs of Financial Crises: Resource Misallocation, Productivity and Welfare in the 2001 Argentine Crisis
Financial crises in emerging market countries appear to be very costly: both output and a host of partial welfare indicators decline dramatically. The magnitude of these costs is puzzling both from an accounting perspective -- factor usage does not decline as much as output, resulting in large falls in measured productivity -- and from a theoretical perspective. Towards a resolution of this puzzle, we present a framework that allows us to (i) account for changes in a country's measured productivity during a financial crises as the result of changes in the underlying technology of the economy, the efficiency with which resources are allocated across sectors, and the efficiency of the resource allocation within sectors driven both by reallocation amongst existing plants and by entry and exit; and (ii) measure the change in the country's welfare resulting from changes in productivity, government spending, the terms of trade, and a country's international investment position. We apply this framework to the Argentine crisis of 2001 using a unique establishment level data-set and find that more than half of the roughly 10% decline in measured total factor productivity can be accounted for by deterioration in the allocation of resources both across and within sectors. We measure the decline in welfare to be on the order of one-quarter of one years GDP.
Urban Structure and Growth
Most economic activity occurs in cities. This creates a tension between local increasing returns, implied by the existence of cities, and aggregate constant returns, implied by balanced growth. To address this tension, we develop a theory of economic growth in an urban environment. We show that the urban structure is the margin that eliminates local increasing returns to yield constant returns to scale in the aggregate, which is sufficient to deliver balanced growth. In a multi-sector economy with specific factors and productivity shocks, the same mechanism leads to a city size distribution that is well described by a power distribution with coefficient one: Zipf's Law. Under certain assumptions our theory produces Zipf's Law exactly. More generally, it produces the systematic deviations from Zipf's Law observed in the data, including the under-representation of small cities and the absence of very large ones. In general, the model identifies the standard deviation of industry productivity shocks as the key parameter determining dispersion in the city size distribution. We present evidence that the relationship between the dispersion of city sizes and the variance of productivity shocks is consistent with the data.
Firm Size Dynamics in the Aggregate Economy
Why do firm growth and exit rates decline with size? What determines the size distribution of firms? This paper presents a theory of firm dynamics that simultaneously rationalizes the basic facts on firm growth, exit, and size distributions. The theory emphasizes the accumulation of industry specific human capital in response to industry specific productivity shocks. The theory implies that firm growth and exit rates should decline faster with size, and the size distribution should have thinner tails, in sectors that use human capital less intensively, or correspondingly, physical capital more intensively. In line with the theory, we document substantial sectoral heterogeneity in US firm dynamics and firm size distributions, which is well explained by variation in physical capital intensities.
With age comes immaturity: Do countries with older populations issue shorter maturity debt?
Recent work has found that countries with older populations face steeper yield curves and issue shorter maturity debt than do younger countries. We reexamine these findings using a new database of public debt maturity and yields for OECD countries. We first show that the behavior of eurozone countries in the pre-euro period drives these results. Next, including more recent data from the post-euro period, we show that the relationship between population age, maturity, and yield curve slopes disappears. This finding is robust to excluding high-credit-risk countries. Last, we show that these patterns reemerge after the European debt crisis, suggesting that eurozone capital markets have resegmented
The Stock of External Sovereign Debt: Can We Take the Data At ‘Face Value’?
The stock of sovereign debt is typically measured at face value. This is a misleading indicator when debts are issued with different contractual forms. In this paper we construct a new measure of the stock of external sovereign debt for 100 developing countries from 1979 to 2006 that is invariant to contractual form, and illustrate five problems with debt stocks measured at face value. First, we show that correcting for differences in the contractual form of debt paints a very different quantitative, and in some cases also qualitative, picture of the stock of developing country external sovereign debt. Second, rankings of indebtedness across countries, which were historically used to define eligibility for debt forgiveness, are sometimes inverted once we correct for differences in contractual form. Third, the empirical performance of the benchmark quantitative model of sovereign debt deteriorates by between 40 to 70 percent once model-consistent measures of debt are used. Fourth, we show how the spread of aggregation clauses in debt contracts which award creditors voting power in proportion to the contractual face value may introduce inefficiencies into the process of restructuring sovereign debts. Fifth, we show how the use of contractual face values gives issuing countries the ability to manipulate their debt stock data, and illustrate the use of these techniques in practice.
Novel genetic loci associated with hippocampal volume
The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (rg =-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness
Anxiety, depression, and peer relationships during adolescence: Results from the Portuguese national health behaviour in school-aged children survey
Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures
Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo
Plasma lipid profiles discriminate bacterial from viral infection in febrile children
Fever is the most common reason that children present to Emergency Departments. Clinical signs and symptoms suggestive of bacterial infection ar