GrAPHiST (Géovisualisation pour l’Analyse des PHénomènes Spatio-Temporels) is a visualization software, which aims to provide an exploratory analysis of spatio-temporal phenomena, through the identification of patterns in the spatio-temporal distribution of event data (historical data, epidemiological data, criminal-record data, meteorological data, … ).
The objective of GrAPHiST is to allow a generic exploratory analysis, which could be applied on different kinds of phenomena, and which could allow the identification of several spatio-temporal dynamics, related to different spatial and temporal (linear or cyclic) scales.
The following video shows the general principles of GrAPHiST.
The following video shows an application of GrAPHiST on data related to storm events, which happened in USA from 2004 to 2018. This analysis allows to identify:
– an annual increase of the number of storm events during summer;
– a general increase of the number of storm events from 2004 to 2018;
– spatio-temporal concentrations of events, which show particular temporal distributions of storm events in specific spatial areas (storm events which occur around Louisiana look to appear mainly in the beginning of the year, whereas storms events look to appear mainly in summer for the whole of USA).
The following video shows an application of GrAPHiST on data related to battles of the american civil war. This analysis allows to identify:
– spatio-temporal clusters of events, which correspond to important episodes of the conflict
– spatial propagations of events along time, which correspond to displacements of the battle line, following the advance of armies.
We believe that a similar analysis could be applied on epidemiological data, in order to identify vectors of propagation of diseases, through the identification of the spatial diffusion of diseases cases along time.