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Reproduction by seed promotes genetic diversity in maguey (Agave salmiana), and if fertilization is adequate, it can increase growth. In pulque maguey, although reproduction by seed is not a common practice, its study is necessary. For this reason, the objectives of this study were 1) to evaluate the effect of organic and chemical fertilization on growth and 2) to determine the CO2 exchange rate (CER) in two conditions of soil moisture in three variants of A. salmiana (subsp. crassispina, var. salmiana and var. ferox) obtained from seed in San Bartolomé Actopan, municipality of Temascalapa, State of Mexico. The hypothesis was that plants treated with chemical fertilizer will have greater growth than those treated with organic fertilizer and the control, and plants fertilized with organic and chemical fertilizer will have a higher CER in two conditions of soil moisture. The experimental design was completely randomized with n=11 for growth variables, n=3 for nutrient content and CO2 exchange rate. Growth was measured every month in 2.9- to 3.6-yearold plants, and CO2 exchange rate was measured in 3.6-yearold plants with irrigation and in 3.75-year-old plants under water stress. Organic fertilizer from pig manure favored plant height and diameter and number of leaves. The subespecies crassispina had the highest values of the evaluated variables, and A. salmiana var. salmiana cultivated with chemical fertilization was outstanding for the number of shoots emitted. The highest CO2 exchange rate occurred between 22:00 and 02:00 h and was higher in plants with abundant soil moisture (irrigated) than in plants with moisture below permanent wilting point. In the latter condition, the plants grown with organic and chemical fertilizer assimilated 60% more CO2 than the control. [ABSTRACT FROM AUTHOR]

This article aims to compare distinct metrics of the value at risk (VaR), differing from prior studies with respect about compare three asset categories belonging to seven countries. Since VaR inception, several approaches were developed to improve the loss estimation accuracy. However, there is hardly a universal consensus on which approach is the most appropriate, since VaR depends on statistical properties of the target asset and the market in which it is traded. It is relevant to compare the results obtained not only among the assets, but also among the markets in which they are traded, considering their specifics properties to verify if there is any pattern of the methods for the data. Considering the three asset categories, the semiparametric and non-parametric models obtained the lowest rejections number. It was also found that the models tested were not effective for the estimation of exchange rate VaR, which may be due to more relevant risks than the market in it asset price formation. Five models belonging to the parametric, semiparametric, and non-parametric approaches were tested. The analyses were divided in two, aiming to test the VaRs performances in distinct economic cycles; the first analyses considered a 1,000 days estimation window, while the second one considered a 252 days estimation window. To validated the results statistically, were applied the Kupiec and the Christoffersen tests. The results show that the conditional VaR and historical simulation have the best performance to estimate VaR. Comparing the markets, Chinese assets were the ones with the highest average number of tests rejections, which can be a consequence of its closed economy. Finally, it was found that shorter estimation window tends to perform better for high volatility assets, while longer window tends for lower volatility assets. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this article is to model a minute series of exchange rates for the EUR/USD pair using the singular spectrum analysis (SSA) and ARIMA-GARCH methods and evaluate which one offers better forecasts for a five-minute horizon. Originality/value: Despite being a successful technique in other branches of science, the application of SSA in finance is quite new. Furthermore, exchange rate modeling is a complex problem, comprising statistical concepts and properties. However, despite the complexity, the analysis of this series is extremely important for several agents playing, directly or indirectly, a role in the economy and the financial market. Design/methodology/approach: Time series models were estimated using the ARIMA-GARCH and SSA techniques, taking into account three samples of the ask exchange rate (closing): uptrend, downtrend, and no well-defined trend. Findings: The forecasts carried out by the SSA were the ones closest to the original observations for the three cases. Regarding the quality measurements, SSA obtained the best results for both uptrend and downtrend samples; for the sample with no well-defined trend, the findings indicated that the ARIMA-GARCH technique attained better results. However, it was concluded that the SSA forecasts, regarding exchange rates during the studied period, are more appropriate than the ones obtained by the ARIMA-GARCH model, regardless of the market movement. [ABSTRACT FROM AUTHOR]

In 1914, the Ottoman Empire was involved in the World War I, ended with economic disruptions due to trade restrictions and higher risks on production after four years. The conflicts were also correlated with increasing expenditures and monetary instabilities. The war heralded the partitioning of the Empire by the Allies, the occupation, and struggle against them over time. It was argued that when Bulgaria asked for an armistice in September 1918, the Ottoman Empire went into recession, heralding the exit of the war. On the other hand, the Ottoman newspapers provided information on the presence of the economic recovery by the end of the war. Using the Ottoman newspapers (i.e., Tasvir-i Efkâr and Vakit) and data on foreign exchange rates and prices in İstanbul Bourse, this paper empirically examines the Ottoman economy by the end of the conflicts. In comparison to traditional sources on the Ottoman history, the newspapers include contemporary and detailed information and data. The paper's contribution is important, as no large literature exists on the topic. The findings imply an economic recovery while the conflicts were ending. This effect, however, disappeared in the long run, since there was an economic recession. [ABSTRACT FROM AUTHOR]