...
Here issues are displayed in a levelled dependency tree according to issue hierarchy. The hierarchy can be customised on the Issue Hierarchy configuration page. If not configured, the graph will follow the deafult issue hierarchy. In the example below you can see that the default hierarchy has been customised and the ‘Task’ issue type has been granted seniority over the ‘Story’ issue type, while other issue types have regained their default rank.
...
Heat map
The heat maps view shows the concentration of issues through heat points. It presents the proportional importance of values within a specific field for issues obtained from a JQL query within a particular context. Each heat point corresponds to a distinct field value, with its size reflecting the number of issues associated with that value.
...
Graph filters
Data displayed in the graph can be filtered by a number of variables:
...