Since market behavior is volatile, this research intends to help investors and business organizations make forecasts with certainty and, as a consequence, with the least possible error in order to succeed in the management of their projects and operations. Elements such as inflation rate, exchange rate, stock prices, economic and financial results, sales, among other variables, are causes of concern for investors. Due to their data structure, these financial instruments correspond to time series, which take values or realizations along time and are spaced over time. The previous behavior of the series is used to forecast its value, return and volatility. It must be taken into consideration that forecasting using traditional techniques might result in imprecisions, so it is necessary to forecast using econometric models because of their robustness and precision. These are also known as un...

The economic and financial crises in the world are recurrent due to the presentation of different patterns. These crises have affected the returns of the private pension system in Peru and there were no effective responses from the Pension Fund Administrators (AFPs). By using the Box and Jenkins or Autoregressive Integrated Moving Average (ARIMA) methodology, the behavior of the monthly average returns of the daily quota values of the type 2 fund—which began in December 2005—of each AFP can be described and forecast. Type 2 funds are distributed 55% in fixed income and 45% in equities, with a balanced profile destined for workers between 45 and 60 years old. The data type of the monthly average returns of the type 2 fund corresponds to the weak stationary time series, since the first moments such as the mean and the variance and autocovariance are time‑invariant.

Since market behavior is volatile, this research intends to help investors and business organizations make forecasts with certainty and, as a consequence, with the least possible error in order to succeed in the management of their projects and operations. Elements such as inflation rate, exchange rate, stock prices, economic and financial results, sales, among other variables, are causes of concern for investors. Due to their data structure, these financial instruments correspond to time series, which take values or realizations along time and are spaced over time. The previous behavior of the series is used to forecast its value, return and volatility. It must be taken into consideration that forecasting using traditional techniques might result in imprecisions, so it is necessary to forecast using econometric models because of their robustness and precision. These are also known as un...

Los instrumentos financieros como el precio de las acciones poseen desenvolvimientos volátiles que ocasionan inquietudes en todo tipo de inversionistas. Por su estructura de datos, el precio de las acciones pertenece a las series de tiempo, porque toma valores en la línea del tiempo. Los inversionistas buscan rentabilidades cuando invierten en instrumentos financieros, razón por lo cual necesitan entender su comportamiento y pronosticarlos con el mínimo error posible, es en esta parte cuando se presentan dos enfoques predictivos diametralmente opuestos; una de estas posiciones, sostiene que el precio de las acciones tiene patrones repetitivos a lo largo del tiempo, y que la información del pasado es útil para realizar predicciones, concluyendo que estos patrones se repetirán en el futuro, sin embargo, sus detractores argumentan que esto no es posible, dado el comportamiento eficie...

Iron (Fe) deficiency, in comparison with magnesium (Mg) and manganese (Mn) deficiencies, is an important factor that causes leaf chlorosis when growing arugula hydroponically. In this study, an experimental design was applied, using randomized complete blocks with four groups of six plants each: three experimental groups (EG) and one control group (CG). Precautions were taken to ensure that intervening variables such as artificial oxygenation and time did not affect the outcome of the experiment. The results obtained show that Fe, Mg, and Mn deficiency in each treatment influences the appearance of leaf chlorosis. Likewise, it is evident that the shortage of oxygenation and the excess of macronutrients influence the chlorosis and necrosis of the arugulae, respectively.