Information and uncertainty
The mathematical concept of information is related to its measurement. In the information theory, a probabilistic approach is taken into account the value of information for the recipient. The receiver has a definite idea of the possible appearance of certain events. These representations are generally unreliable and are described by the probabilities with which an occurrence of an event from a complete set of known events is expected. The general measure of uncertainty is characterized by some function of the totality of these probabilities. The information character of an event is determined by how much the measure of uncertainty decreases after its appearance. The message carries full information about this set of events if it completely removes all uncertainty. For example, if there are five balls with different numbers in the bag, then removing one ball from the bag and determining its number, you can reduce the uncertainty by 1/5, and after the fifth ball is seized, the uncertainty is removed completely, as all the ball numbers become known.
Information Quality Indicators
The possibility and efficiency of using information by the consumer are determined by the indicators of its quality, which are usually asked at the stage of developing the information system. The most important indicators of information are:
• accuracy, is determined by the degree of its proximity to the real state of the object, process, phenomenon, etc. With respect to the information represented in binary form, the value of the first least significant digit of the number can be used to determine the accuracy;representativeness, determined by the correctness and validity of the selection of the essential features and relationships of the displayed phenomenon;
• availability for user perception, provided by the appropriate procedures for obtaining it;
• content, reflecting the semantic capacity equal to the ratio of the amount of semantic information in the message to the amount of data being processed;
• sufficiency (completeness), determined by the minimum set of indicators to make the right decision. The concept of completeness of information is associated with its semantic content (semantics) and consumer properties (pragmatics);
• relevance, , determined by the degree of preservation of the value of information at the time of its use. This indicator refers to information that changes over time;
• Reliability, is determined by its ability to reflect existing objects with the required accuracy. The unit of confidence can be the confidence probability of the required accuracy;
stability, reflecting its ability to maintain accuracy when changing the original data.