1.  An obvious advantage of the hierarchical model is that the reinvestigation is conducted by more experienced investigators.

2.  It is difficult to establish the precise rationale for the traditional hierarchical model which pervades the educational system.

3.  The skyscraper metaphor is apt, for our only hope to understanding such complexity is with a hierarchical model.

4.  This is depicted in the three-level hierarchical model shown in Fig.

5.  In the hierarchical model the data structures are represented by trees with the top entity referred to as the root.

6.  The connections or links are explicit in the hierarchical model.

7.  It is possible to express many-to-many relationships using the hierarchical model, but only by creating two hierarchies.