Decision Support Systems are software systems that identify, process, compile and help evaluate information relevant to human decision-makers for operational and strategic tasks. This includes functions for sorting and filtering data, its flexible presentation as well as evaluation options such as totals or average calculations, comparisons, etc. Further functions allow the execution of model calculations (scenarios, forecasts) and the linking of the data with optimization algorithms. The following are important:
- Flexible adaptation to changing content and technical conditions and changing issues
- Flexible change of classifications of the relevance of information
- Easy to use, even by the decision-makers themselves
- The interpretation, evaluation and evaluation of the information and decision-making remains a matter for humans. The task of the system is to present the information clearly and to automatically point out special features, such as highlighting limit value exceedances.
In addition to this task of evaluating merged data, there is also the collection, updating and management (such as historizing and deleting) of individual information.
Efforts to create such systems have been undertaken since the early beginnings of the computer age (from the mid-1950s onwards), when data sets created for operational purposes and a progressive development of computing power triggered requests for more extensive information. And new, expanded system components of this kind are still being created, driven by new requirements and made possible by technical advancements.
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Technology Behind and Related to Decision Support System
General Ledger
The GL picks up on the pure account assignment processes of business accounting (which can only contribute to decision-making to a limited extent due to its primarily external addressees) and offers the option of enriching them with information that can be evaluated (customer number, plant, material item, etc.). See General Ledger Accounting.
Management Information System (MIS)
MIS is the only system that is no longer used in its original form, as it was very complicated to use: a dedicated department of technicians was assigned to create the reports, as file systems at the time could only be accessed by keys.
DSS (Decision Support Systems)
DSS was the first approach that brought support to management (but also to landscape management and disaster management), as models and methods were stored in a DSS to carry out simulations.
EIS/FIS (Command Information System)
Since the required evaluations were usually carried out at a hierarchical level below top management and these were then manually prepared graphically in order to present them, a system was developed with which management could directly access graphical evaluations – leadership information system.
Data Warehouse
The EIS has always been (rightly) accused of being too superficial, as the data layer plays only a secondary role. The data warehouse is a kind of return to the essentials; the data layer. Today, a data warehouse is typically accessed using an OLAP system or EIS. It can serve as a database for a decision support system.
OLAP
Online Analytical Processing is the multidimensional storage and evaluation of data in the format of so-called OLAP cubes.
Business Intelligence
Business intelligence refers to tools for distributing information within the company in the form of KPI cockpits, reports and analyses.
Business Performance Management
Business performance management is the extension of the business intelligence approach to include process-oriented tools for planning, forecasting, and simulation.