ABSTRACT
This chapter aims to investigate if terrorism has increased over time, and if so, in which time period and geographical areas has the increase of terrorism been observed. It explores temporal changes of terrorism with data from 2002 to 2017 and observe their evolution worldwide, and zoom into finer spatial level analysis to identify patterns at the level of continent, country, and city. Times series data can be decomposed into three or more components, which can be multiplied or added. The trend component of a time series informs us on deterministic long-term behavior in the series; a positive trend term may reveal an upward pattern. Changes in temperature are also caused by phenomena that are virtually impossible to predict, such as micro variations of the wind direction and magnitude that operate at very fine spatial and temporal scales.
