Armed Conflict Exposure, Human Capital Investments and Child Labor: Evidence from Colombia

Using a unique combination of household and violence data sets and a duration analysis methodology, this paper estimates the effect that exposure to armed conflict has on school drop-out decisions of Colombian children between the ages of six and seventeen. After taking into account the possible endogeneity of municipal conflict related events through the use of instrumental variables, we find that armed conflict reduces the average years of schooling in 8.78% for all Colombian children. This estimate increases to 17.03% for children between sixteen and seventeen years old. We provide evidence that such effect may be induced mainly through higher mortality risks, and to lesser extent due to negative economic shocks and lower school quality; all of which induce a trade-off between schooling and child labor.Armed con.ict, School drop-out, Duration Analysis, Colombia

Compactness estimates for Hamilton-Jacobi equations depending on space

We study quantitative estimates of compactness in $\mathbf{W}^{1,1}_{loc}$ for the map $S_t$, $t>0$ that associates to every given initial data $u_0\in \mathrm{Lip}(\mathbb{R}^N)$ the corresponding solution $S_t u_0$ of a Hamilton-Jacobi equation $$u_t+H\big(x, \nabla_{\!x} u\big)=0\,, \qquad t\geq 0,\quad x\in \mathbb{R}^N,$$ with a convex and coercive Hamiltonian $H=H(x,p)$. We provide upper and lower bounds of order $1/\varepsilon^N$ on the the Kolmogorov $\varepsilon$-entropy in $\mathbf{W}^{1,1}$ of the image through the map $S_t$ of sets of bounded, compactly supported initial data. Quantitative estimates of compactness, as suggested by P.D. Lax, could provide a measure of the order of "resolution" and of "complexity" of a numerical method implemented for this equation. We establish these estimates deriving accurate a-priori bounds on the Lipschitz, semiconcavity and semiconvexity constant of a viscosity solution when the initial data is semiconvex. The derivation of a small time controllability result is also fundamental to establish the lower bounds on the $\varepsilon$-entropy.Comment: 36 pages. arXiv admin note: text overlap with arXiv:1403.455

Landau Cooling in Metal-Semiconductor Nanostructures

An electron-cooling principle based on Landau quantization is proposed for nanoscale conductor systems. Operation relies on energy-selective electron tunneling into a two-dimensional electron gas in quantizing magnetic fields. This quantum refrigerator provides significant cooling power (~1 nW at a few K for realistic parameters) and offers a unique flexibility thanks to its tunability via the magnetic-field intensity. The available performance is only marginally affected by nonidealities such as disorder or imperfections in the semiconductor. Methods for the implementation of this system and its characterization are discussed.Comment: 4 pages, 4 color figure

The different faces of branes in Double Field Theory

We show how the Wess-Zumino terms of the different branes in string theory can be embedded within double field theory. Crucial ingredients in our construction are the identification of the correct brane charge tensors and the use of the double field theory potentials that arise from dualizing the standard double field theory fields. This leads to a picture where under T-duality the brane does not change its worldvolume directions but where, instead, it shows different faces depending on whether some of the worldvolume and/or transverse directions invade the winding space. As a non-trivial by-product we show how the different Wess-Zumino terms are modified when the brane propagates in a background with a non-zero Romans mass parameter. Furthermore, we show that for non-zero mass parameter the brane creation process, when one brane passes through another brane, gets generalized to brane configurations that involve exotic branes as well.Comment: 23 pages + Appendi

Is justice blind? An examination of disparities in homicide sentencing in Colombia, 1980-2000

Evidence has repeatedly shown that disparities in crime sentences can be attributed to certain variables considered outside the legal dimensions of the case. The majority of research that investigates factors that contribute to such disparities has primarily focused on crimes of varying severities adjudicated in the U.S. court system. We expand research on this topic by focusing on disparities in homicide sentences using data from over 9000 homicide cases tried in Colombia from 1980 - 2000. We specifically explore whether judges use substantive rationality when deciding the length of the offender´s sentence and if the sentence should be above the legal minimum set for the severity of the crime according to the criminal code under which it is adjudicated. Results reveal that disparities in homicida sentences can be attributed to extra-legal variables such as: the city in which the homicide trial took place, where the body of the victim was retrieved, and whether the defendant was identified by an ID parade. However, we also find evidence that suggests that legal variables such as the defendant´s previous criminal record and the aggravating circumstances of the case engender greater differences in sentence outcomes than non-legal variables previously mentioned. Explanations and policy implications are discussed.Sentence Disparities, Homicide, Colombian Criminal Law

Does it matter (for equilibrium determinacy) what price index the central bank targets?

What inflation rate should the central bank target? The authors address determinacy issues related to this question in a two-sector model in which prices can differ in equilibrium. They assume that the degree of nominal price stickiness can vary across sectors and that labor is immobile. This paper’s contribution is to demonstrate that a modified Taylor principle holds in this environment. If the central bank elects to target sector A and responds to price movements in this sector with a coefficient greater than unity, then this policy rule will ensure determinacy across all sectors. These results have at least two implications: First, the equilibrium-determinacy criterion does not imply a preference for any particular inflation measure. Second, since the Taylor principle applies at the sectoral level, the principle is unnecessary at the aggregate level.Monetary policy ; Inflation (Finance) ; Banks and banking, Central

Explicit inflation objectives and macroeconomic outcomes

We find evidence that adopting an explicit inflation objective plays a role in anchoring long-run inflation expectations and in reducing the intrinsic persistence of inflation. For the period 1994-2003, private-sector long-run inflation forecasts exhibit significant correlation with lagged inflation for a number of industrial economies, including the United States. In contrast, this correlation is largely absent for the five countries that maintained explicit inflation objectives over this period, indicating that these central banks have been reasonably successful in delinking expectations from realized inflation. We also show that the null hypothesis of a random walk in core CPI inflation can be clearly rejected for four of these five countries, but not for most of the other industrial countries. Finally, we provide some evidence concerning the initial effects of the adoption of explicit inflation objectives in a number of emerging-market economies. JEL Classification: E31, E52, E58Consensus Forecasts, inflation expectations, inflation persistence

The macroeconomic effects of inflation targeting

Macroeconomics ; Inflation (Finance)