Applying the theory of real options to the optimal timing of timber harvests

Se propone el enfoque de opciones reales como herramienta económico-financiera para la toma de decisiones estratégicas en el sector forestal. En términos de instrumentos financieros, consideraremos en particular una opción exótica conocida como barrier option del tipo knock-in. Suponemos que la proyección del precio de venta promedio de los subproductos sigue un proceso estocástico del tipo Geométrico Browniano, mientras que la producción se determina mediante simulación de un turno forestal. La decisión de talar la masa forestal surge de comparar en cada periodo, el valor de flujo de fondos en cada nodo (FFij(t)) de una rejilla binomial con el valor esperado en el próximo año (X t+1 x e−rΔ t) ). En un ejemplo analizado el criterio tradicional del VAN indica que el mayor valor actual se produce en el instante t = 0 (año 10), mientras que el enfoque de opciones reales arroja que el máximo valor de ejercicio se da en el periodo t = 8 (año 18).We present here a real options approach as a tool for strategic decision-making in the forestry sector. We consider, in particular, an exotic option known as a knock-in barrier option. We use this approach to determine the optimal timing of harvests. The optimal time is determined by comparing at each period, the cash flow corresponding to each node (FFij(t)) in a binomial lattice with the expected value in the next year (X t+1 x e−rΔ t). The traditional NPV indicates, in an hypothetical context analyzed in the paper, that the largest present value is obtained at the tenth year of standing. The real options approach championed here, instead, indicates that the highest value is at the eighteenth year of standing.Fil: Milanesi, Gastón. Universidad Nacional del SurFil: Woitschach, Guillermo B. M.. Universidad Nacional del SurFil: Broz, Diego R.. Universidad Nacional del Su

Aplicación de la teoría de opciones reales a la determinación del momento óptimo de cosecha forestal

Se propone el enfoque de opciones reales como herramienta económico-financiera para la toma de decisiones estratégicas en el sector forestal. En términos de instrumentos financieros, consideraremos en particular una opción exótica conocida como barrier option del tipo knock-in. Suponemos que la proyección del precio de venta promedio de los subproductos sigue un proceso estocástico del tipo Geométrico Browniano, mientras que la producción se determina mediante simulación de un turno forestal. La decisión de talar la masa forestal surge de comparar en cada periodo, el valor de flujo de fondos en cada nodo (FFij(t)) de una rejilla binomial con el valor esperado en el próximo año ( ). En un ejemplo analizado el criterio tradicional del VAN indica que el mayor valor actual se produce en el instante t = 0 (año 10), mientras que el enfoque de opciones reales arroja que el máximo valor de ejercicio se da en el periodo t = 8 (año 18).Se propone el enfoque de opciones reales como herramienta económico-financiera para la toma de decisiones estratégicas en el sector forestal. En términos de instrumentos financieros, consideraremos en particular una opción exótica conocida como barrier option del tipo knock-in. Suponemos que la proyección del precio de venta promedio de los subproductos sigue un proceso estocástico del tipo Geométrico Browniano, mientras que la producción se determina mediante simulación de un turno forestal. La decisión de talar la masa forestal surge de comparar en cada periodo, el valor de flujo de fondos en cada nodo (FFij(t)) de una rejilla binomial con el valor esperado en el próximo año ( ). En un ejemplo analizado el criterio tradicional del VAN indica que el mayor valor actual se produce en el instante t = 0 (año 10), mientras que el enfoque de opciones reales arroja que el máximo valor de ejercicio se da en el periodo t = 8 (año 18)

Homework and Academic Achievement in Latin America: A Multilevel Approach

The relationship between homework and academic results has been widely researched. Most of that research has used English-speaking, European or Asian samples, and to date there have been no detailed studies into that relationship in Latin America and the Caribbean. The aim of this study is to examine the effect of quantitative homework characteristics on achievement in science. The sample comprised 61,938 students at 2,955 schools in the 15 Latin American countries (plus the Mexican state of New Leon) which participated in the Third Regional Comparative and Explanatory Study (TERCE), carried out by the Latin American Laboratory for Educational Quality (LLECE) in 2013. The mean age was 12.42 years old (±0.94). Within each country, three hierarchical-linear models were applied at two levels: student and school. The individual level considered time spent doing homework and the school level considered the amount and frequency of homework assignment. In addition, ten control variables were included in order to control the net effect of the characteristics of the homework on the result. The results confirmed that homework is widely assigned in the Latin American region. At the individual level, time spent on homework had little effect on academic performance, while in the quantitative homework characteristics it was the frequency of homework assignment which demonstrated a clearer effect rather than the amount of homework assigned

Genome sequencing in families with congenital limb malformations

The extensive clinical and genetic heterogeneity of congenital limb malformation calls for comprehensive genome-wide analysis of genetic variation. Genome sequencing (GS) has the potential to identify all genetic variants. Here we aim to determine the diagnostic potential of GS as a comprehensive one-test-for-all strategy in a cohort of undiagnosed patients with congenital limb malformations. We collected 69 cases (64 trios, 1 duo, 5 singletons) with congenital limb malformations with no molecular diagnosis after standard clinical genetic testing and performed genome sequencing. We also developed a framework to identify potential noncoding pathogenic variants. We identified likely pathogenic/disease-associated variants in 12 cases (17.4%) including four in known disease genes, and one repeat expansion in HOXD13. In three unrelated cases with ectrodactyly, we identified likely pathogenic variants in UBA2, establishing it as a novel disease gene. In addition, we found two complex structural variants (3%). We also identified likely causative variants in three novel high confidence candidate genes. We were not able to identify any noncoding variants. GS is a powerful strategy to identify all types of genomic variants associated with congenital limb malformation, including repeat expansions and complex structural variants missed by standard diagnostic approaches. In this cohort, no causative noncoding SNVs could be identified. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00439-021-02295-y

A real options approach to the determination of optimal harvesting age for two kinds of forest management

It was studied Real Options approach as a financial-economic tool for strategic decision-making in the determination of optimal harvesting age in two kinds of forestry exploitation, a high-value one and a pulp-producing unit. It is assumed that the projection of selling prices of the byproducts follows a Brownian geometric stochastic process, while production is determined by means of a simulation of forestry turnover. The decision of when to harvest arises from the comparison, at each period, of the cash-flow at each node ( FFij(t)) of a binomial lattice and its expected value in the next period (Xt+1.e-∆t ). The Real Values approach indicates that the optimal ages are at 18 years for high-value units and 17 years for pulp producing ones

A second cohort of CHD3 patients expands the molecular mechanisms known to cause Snijders Blok-Campeau syndrome

There has been one previous report of a cohort of patients with variants in Chromodomain Helicase DNA-binding 3 (CHD3), now recognized as Snijders Blok-Campeau syndrome. However, with only three previously-reported patients with variants outside the ATPase/helicase domain, it was unclear if variants outside of this domain caused a clinically similar phenotype. We have analyzed 24 new patients with CHD3 variants, including nine outside the ATPase/helicase domain. All patients were detected with unbiased molecular genetic methods. There is not a significant difference in the clinical or facial features of patients with variants in or outside this domain. These additional patients further expand the clinical and molecular data associated with CHD3 variants. Importantly we conclude that there is not a significant difference in the phenotypic features of patients with various molecular disruptions, including whole gene deletions and duplications, and missense variants outside the ATPase/helicase domain. This data will aid both clinical geneticists and molecular geneticists in the diagnosis of this emerging syndrome

Plato argénteo nº 38.215 . Cabeza antropomorfa diademada - ABE0162_AR

Proyectos del Plan Nacional I+D+I con referencias PB94-0129, PB97-1132, BHA 2002-00138, HUM 2006-06250/HISTProyectos de la CAM con referencias 06/0020/1997, 06/0094/1998, 06/0090/2000, 06/0043/2001Programa Consolider-Ingenio 2010 con sigla CSD2007-00058NoMuseo Arqueológico Nacional (Madrid)AbengibrePlato argénteo nº 38.215 . Cabeza antropomorfa diademad