Graph$-1$: The concept of graphical analysis can be applied to this dataset. The below constructed graph will be used in some of the queries in this section. Consider all patients admitted in $500$ of the earliest admissions. These patients will be the nodes of the graph. Consider here only $500$ of the earliest admissions. There exists an undirected edge between $2$ patients if they were admitted in the hospital at least once in an overlapping period with at least one common diagnosis in that overlapping admission. This forms an undirected unweighted graph. Note that there are no self edges in the graph.