Design And Implementation Of A Distributed Recruitment Management System

2.6.3    Decision Support Disciplines
The above broad definition of DS encompasses a number of more specialized disciplines; some most important ones are briefly overviewed in this section.
2.6.3.1    Operations Research (OR)
This is concerned with optimal decision making in, and modelling of, deterministic and probabilistic systems that originate from real life (Hillier, 2000).
These applications, which occur in government, business, engineering, economics, and the natural and social sciences, are characterized largely by the need to allocate limited resources. The contribution from OR stems primarily from:
=>   Structuring the real-life situation into a mathematical model, abstracting the essential elements so that a solution relevant to the decision maker's objectives can be sought. This involves looking at the problem in the context of the entire system.
=>    Exploring the structure of such solutions and developing systematic procedures for obtaining them.
=>  Developing a solution, including the mathematical theory, if necessary, that yields an optimal value of the system measure of desirability.
Typical OR techniques include linear and nonlinear programming, network optimization models, combinatorial optimization, multi-objective decision making, and Markov analysis. Also, OR is often associated with Management Sciences and Industrial Engineering.
2.6.3.2    Decision Analysis Decision Analysis (DA)
This is popularly known as “Applied Decision Theory”. It provides a framework for analysing decision problems by (Clemen, 1996):
=>   structuring and breaking them down into more manageable parts;
=>   explicitly considering the possible alternatives, available information, involved uncertainties, and relevant preferences;
=>   Combining these to arrive at optimal or “sufficiently good” decisions.
The Decision analysis process usually proceeds by building models and using them to perform various analyses and simulations, such as “what-if” and sensitivity analysis, and Monte Carlo simulation. Typical modelling techniques include decision trees, influence diagrams, and multi-attribute utility models.
2.6.3.3    Decision Support Systems (DSS)
Decision Support Systems (DSS) are defined as interactive computer-based systems intended to help decision makers utilize data and models in order to identify and solve problems and make decisions (Power, 1999). Their major characteristics are:
=>    DSS incorporate both data and models;
=>    They are designed to assist managers in semi-structured or unstructured decision- making processes;
=>    DSS support, rather than replace, managerial judgment;
=>   They are aimed at improving the effectiveness–rather than efficiency–of decisions.
DSS are further classified into four main categories: data, model, process and communication oriented. In addition, there are the so-called DSS Generators, which facilitate the development of dedicated DS Systems. Specifically, the term DSS encompasses many types of information systems that support decision making. These typically include (Power, 1977): Executive Information Systems (EIS), Executive Support Systems (ESS), Geographic Information Systems (GIS), OLAP, Software Agents, Knowledge Discovery Systems, Group DSS, and some types of Expert Systems (ES) (Mallach, 1994).
2.6.3.4    Data Warehousing
Data Warehouse is a repository of multiple heterogeneous data sources, organized under a unified schema in order to facilitate management decision making (Han, 2001). Data warehouse technology includes data cleansing, data integration, and OLAP, that is, analysis techniques with functionalities such as summarization, consolidation, and aggregation, as well as the ability to view information from different angles. In warehouses, data is typically represented in the form of decision cubes.
2.6.3.5    Group Decision Support
Group Decision Support Systems (GDSS) are interactive computer-based systems that facilitate the solution of unstructured problems by a set of decision-makers working together as a group. They aid groups, especially groups of managers, in analyzing problem situations and in performing group decision making tasks (Power, 1999). In addition to data and models of decision, GDSS must take into account the dynamics of the group decision-making process (Mallach, 1994).
Software designed to support the work of a group is often referred to as Groupware. It provides mechanisms that help users coordinate and keep track of on-going projects, and allow people to work together through computer-supported communication, collaboration, and coordination.
Examples of groupware include Lotus №tes and Microsoft Exchange. A closely related discipline is also Computer-Supported Cooperative Work (CSCW), which studies how people work together using computer technology. Typical applications include email, awareness and notification systems, videoconferencing, chat systems, multi-player games, and mediation systems.