The Family of Log-Skew-Normal Alpha-Power Distributions using Precipitation Data

Abstract

We present a new set of distributions for positive data based on a skew-normal alpha-power (PSN) model including a new parameter which in turn makes the log-skew-normal alpha-power (LPSN) model more flexible than both the log-normal (LN) model and log-skew-normal (LSN) model. The LPSN model contains the LN model and LSN model as special cases. Furthermore, it models positive data with asymmetry and kurtosis larger than the one permitted by the LN distribution. Precipitation data illustrates the usefulness of the LPSN model being less influenced by outliers.

Keywords

• asimetría
• curtosis
• estimador máxima verosimilitud
• matriz de información de Fisher
• test de razón de verosimilitud