تهمینه جلالی

In recent years, studies of extreme events has attracted attention of many researchers in the area of complexity science. In this thesis, we study the effects of linear and nonlinear correlations and distribution function on the extreme events of RR interval series which derived from ECG series. These series are related to three categories of humans. The first category includes people with normal heart rhythm and those in both other groups have abnormal heart rhythms. There are two methods to model the distribution of extreme events in a sequence of data, both widely used: the block maxima method and the peaks-over-threshold method. In this thesis we use these two approaches. Our studies show that the distribution of extreme events in RR interval series of any people in the study, is affected by linear and nonlinear correlations and distribution of RR interval series. moreover, both block maxima and peaks over threshold approaches are complementary to each other and both of them can distinguish between people with normal and abnormal heart rhythm from distribution of extreme events in their RR interval series.