Skew symmetric κατανομές και εφαρμογές τους
Skew symmetric distributions and applications
The skew-symmetric distributions exhibit the versatility characteristic in relation to the corresponding conventional ones due to the existence of the additional feature of skewness. The aim of this diploma thesis is to analyze the main types of the skew-symmetric distributions by recording the basic relations, theorems, principles and properties that characterize them. This analysis is considered as an important one due to the increasingly frequent need to use skew-symmetric distributions in applications, where the actual data do not adequately follow the usual symmetric distributions. The properties of the skew-symmetric distributions, according to the usual used symmetric distributions, such as normal distribution, logistic distribution and t-distribution that seem to be very useful in the modern field of the science of statistics. On the practical part of the thesis, in which the R language is used, through the creation of code take part the graphs of the so-called " Probability-Density-Function” of the distributions, which are also analyzed in the theoretical part as well as their functions and characteristics that are presented for a more complete comprehension and presentation of these distributions as they are not very well known.