Because XML data is not based on a traditional relational model, implementing XML repositories using such databases can be complex and cumbersome. For example, every level of XML hierarchy would ...

In this paper, we describe the hierarchical data model (HDM), which is a performance efficient alternative to the traditional flat CDC verification flow. The HDM is equivalent to an abstract CDC model ...

Hierarchical data analyses in different disciplines are reviewed to compare statistical applications of the Hierarchical Linear Model (HLM) software and the SAS MIXED procedure. Similar features of ...

An example is the analysis of the many types of adverse events (AEs) that are recorded in drug clinical trials. We propose a three-level hierarchical mixed model.