- · Information- knowledge concerning concepts and objects (facts, events, things, processes, ideas) in the human brain;
- · Data- presentation of processed information suitable for transmission, interpretation, or processing (computer files, paper documents, records in the information system).
- 1. Data and information are closely related.
- 2. Data are fixed, they actually exist at every unit of time. Information only arises from the processing of this data.
- 3. Data after transformation becomes information. Information that has been verified many times is knowledge.
- 4. Information, in contrast to data, is a measurable substance.
Modeling the process of making managerial decisions allows you to make a significant step towards quantitative assessments and quantitative analysis of the results of decisions made. The creation and use of models of the decision-making process allows even qualitatively assessed managerial situations to be assessed quantitatively using specially introduced verbal-numerical scales.
The use of modeling the process of making managerial decisions allows raising it to a qualitatively new level, developing and implementing modern technologies into the practice of making managerial decisions. It is the professional use of models of the decision-making process that allows the head of the organization to control his intuition and ensure a greater degree of consistency, consistency and reliability of the managerial decisions made. But on the other hand, the use of models allows you to more fully realize the intuition, experience and knowledge of the decision-maker. It is necessary to understand that the model allows you to find a rational solution only for that simplified version of the decision-making situation that is used in the model.
There are three basic types of models: physical, analog and mathematical
Physical(descriptive or portrait) - depicts an object or situation, showing how it looks. For example: copies of cars, airplanes, miniature drawings of a plant, etc.
Analog- image of an object or situation by other means For example: lake on the map - organizational chart in blue; graphs the ratio of various indicators of the enterprise
Mathematical(symbolic) - the use of symbols to characterize an object in the form of mathematical equations
Based on these basic models, various types of models and methods for making management decisions are developed. Let's consider the most common ones.
Game theory- is used to assess the impact of a decision made on competitors. In business, game models are used to predict the reaction of competitors to changes in prices, sales, new products. This model of rusting is quite rare.
Queuing theory, or optimal service- is used to determine the optimal number of customer service channels in relation to their needs. The principal problem is considered to be balancing the cost of additional channels with services and losses from services at a level lower than the optimal one.
Inventory management model- are used to determine the time of placing orders for resources and their quantities, as well as the mass of finished products in warehouses.
Linear programming model- used to determine the optimal way to allocate scarce resources in the presence of competing needs (planning service differentiation, distribution of workers, etc.)
Simulation modeling- imitation of a specific process or model, its experimental use to determine changes in a real situation
Economic analysis- assessment of costs, profits and profitability of the company often use the break-even method, i.e. determination of the moment from which the enterprise becomes breakeven
Information- information about objects and phenomena environment, their parameters, properties and state, which reduce the existing degree of uncertainty about them, incompleteness of knowledge.
Source (supplier) and consumer (recipient) of information.
Term information comes from the Latin informatio, which means clarification, information, presentation. In a broad sense information is defined as information (messages) about one or another side of the material world and processes. A message is a form of presentation of information in the form of speech, text, images, digital data, graphs, tables, etc.
Information is a general scientific concept that includes the exchange of information between people, the exchange of signals between animate and inanimate nature, people and devices.
It should be remembered that: information exists outside of its creator; information becomes a message as soon as it is expressed in a particular language.
Along with the concept of "information", the concept is often used data. Data can be considered as signs or recorded observations that for some reason are not used, but only stored. Therein
if it becomes possible to use this data to reduce uncertainty about something, the data turns into information. Therefore, it can be argued that information is the data used .
Information is structured data.
Information(in biology) = Biology studies living nature and the concept of "information" is associated with the appropriate behavior of living organisms. In living organisms, information is transmitted and stored using objects of various physical nature (state of DNA), which are considered as signs of biological alphabets. Genetic information is inherited and stored in all cells of living organisms.
Information(in philosophy) = this is interaction, reflection, knowledge.
Information(in cybernetics) = these are the characteristics of the control signal transmitted over the communication line.
The following approaches to the definition of information can be distinguished:
- traditional(common) used in computer science: Information- this is information, knowledge, messages about the state of affairs that a person perceives from the outside world with the help of the senses (sight, hearing, taste, smell, touch).
- probabilistic- used in information theory: Information- this is information about objects and phenomena of the environment, their parameters, properties and condition, which reduce the existing degree of uncertainty and incompleteness of knowledge about them.
Information is stored, transmitted and processed in symbolic (sign) form... The same information can be presented in different forms:
1) Signed writing, consisting of various signs, among which there is a symbolic one in the form of text, numbers, specials. characters; graphic; tabular, etc.
2) In the form of gestures or signals.
3) In oral verbal form (conversation).
The presentation of information is carried out using languages, as sign systems, which are built on the basis of a certain alphabet and have rules for performing operations on signs.
Language- a certain sign system for presenting information.
Natural languages- spoken and written languages. In some cases, spoken language can be replaced by the language of facial expressions and gestures, the language of special signs (for example, road);
Formal languages- special languages for various areas of human activity, which are characterized by a rigidly fixed alphabet, more stringent rules of grammar and syntax. These are the language of music (notes), the language of mathematics (numbers, mathematical signs), number systems, programming languages, etc.
Any language is based on alphabet- a set of symbols / signs.
The total number of characters in the alphabet is usually called the power of the alphabet.
Information carriers- medium or physical body for the transmission, storage and reproduction of information. These are electrical, light, thermal, sound, radio signals, magnetic and laser disks, printed publications, photographs, etc.
Data- this is also knowledge, but knowledge of a very special kind. In a first approximation, data is the result of linguistic recording of a single observation, experiment, fact or situation. Examples of data might be:
a) “on such and such a date, such and such a year, at the moment t it was raining in a certain area” (meteorological data) ”;
b) “the price of commercial timber on such and such a day in such and such a year, according to information from such and such a stock exchange, was so many dollars per ton” (trade data);
c) “the state budget deficit in such and such a country was in such and such a year so many billions of dollars” (financial data);
d) "at such and such a moment in time, the automatic laboratory heading towards Jupiter deviated from the calculated trajectory by so many degrees, so many thousand kilometers in such and such a direction" (data from the sphere of space technology).
From a technological point of view, some specialists usually define the concept of "data" as information that is stored in databases and processed by application programs, or information presented as a sequence of characters and intended for processing in a computer, i.e. data include only that part of knowledge that is formalized to such an extent that formalized processing procedures can be carried out on them using various technical means.
Data is information presented in a formalized form suitable for automatic processing with the possible participation of a person. Data is information recorded (encoded) in the language of a machine... Data are individual facts that characterize objects, processes and phenomena in the subject area, as well as their properties.
There is a difference between information and data; Data can be viewed as signs or recorded observations that, for some reason, are not used, but only stored. Consequently, at a given moment in time, they do not affect behavior, decision-making. However, data is turned into information if such an impact exists.
For example, the main data set for a computer consists of features that do not affect behavior. Until this data is organized appropriately and is not reflected in the output form for the manager to act in accordance with it, it is not information. They remain data until the employee contacted them in connection with the implementation of certain actions or in connection with some decision that he is obliged to take.
Data turns into information when its meaning is realized. You can also say that when it becomes possible to use data to reduce uncertainty about something, the data turns into information.
Data life cycles
Like matter and energy, data can be collected, processed, stored, and reshaped. However, they have some peculiarities. First of all, data can create and disappear. So, for example, data on some extinct animal may disappear when a lump of coal with its imprints is burned. Data can be erased, lost accuracy, etc. Data can be characterized by a life cycle (Fig. 1.9), in which three aspects are of primary importance - origin, processing, storage and retrieval.
Reproduction and use of data can be carried out at different points in their life cycle and therefore are not shown in the diagram.
Rice. 1.9. Data Life Cycle
When processing on a computer, the data is transformed, conditionally going through the following stages:
1) data as a result of measurements and observations:
2) data on tangible media (tables, protocols, reference books);
3) data models (structures) in the form of diagrams, graphs, functions;
4) data in a computer in the language of data description;
5) databases on computer media.
Data models
The data model is the core of any database. The appearance of this term in the early 70s of the twentieth century is associated with the works of the American cybernetist E.F. Codd, which reflected the mathematical aspect of the data model used in the sense of data structure. In connection with the needs of the development of data processing technology in the theory of automated information banks (ABI) in the second half of the 70s, the instrumental aspect of the data model appeared, the content of this term included the restrictions imposed on data structures and operations with them.
In a modern interpretation data model is defined as a set of rules for generating data structures in databases, operations on them, as well as integrity constraints that determine the admissible connections and data values, the sequence of their change.
Thus, a data model is a set of data structures, integrity constraints, and data manipulation operations. On this basis, the following working definition can be formulated: a data model is a collection of data structures and their processing operations.
Currently, there are three main types of data models: hierarchical, network and relational. Hierarchical data model organizes data in the form of a tree structure and is the implementation of logical connections: generic relations or relations "whole - part". For example, the structure of a higher education institution is a multilevel hierarchy (see Figure 1.10).
Rice. 1.10. Example of a hierarchical structure
A hierarchical (tree-like) database consists of an ordered set of trees; more precisely, from an ordered set of several instances of the same type of tree. In this model, the original elements give rise to other elements, and these elements in turn give rise to the next elements. Each child has only one parent. Organizational charts, lists of materials, table of contents in books, project plans, meeting schedules, and many other sets of data can be presented hierarchically.
The main disadvantage of this model is: a) the complexity of displaying the relationship between objects of the "many-to-many" type; b) the need to use the hierarchy that was laid in the basis of the database during the design. The need for constant data reorganization (and often the impossibility of this reorganization) led to the creation of a more general model - network.
The networked approach to organizing data is an extension of the hierarchical approach. This model differs from the hierarchical model in that each child can have more than one parent. An example of a network data model is shown in Figure 1.11.
Since the network database can directly represent all types of connections inherent in the data of the corresponding organization, this data can be navigated, examined and queried in all possible ways, i.e. the network model is not linked by just one hierarchy. However, in order to compose a query to a networked database, it is necessary to delve deeply into its structure (to have a schema of this database at hand) and develop your own mechanism for navigating through the database, which is a significant drawback of this database model.
Rice. 1.11. An example of a network structure
One of the drawbacks of the data models discussed above is that in some cases, with a hierarchical and network representation, the growth of the database can lead to a violation of the logical representation of the data. Such situations arise when new users, new applications and types of queries appear, when other logical relationships between data items are taken into account. The relational data model avoids these disadvantages.
A relational database is one in which all data is presented to the user in the form of rectangular tables of data values, and all operations on the database are reduced to manipulating tables.
A table consists of columns (fields) and rows (records); has a name that is unique within the database. The table reflects the type of object in the real world (entity), and each of its lines is a specific object. So, the Sports section table contains information about all children involved in a given sports section, and its rows represent a set of attribute values for each specific child. Each column in a table is a collection of values for a particular attribute of an object. The Weight column, for example, is a collection of all weight categories of children in the section. The Gender column can only contain two different values: "husband." and "wives." These values are selected from the set of all possible values for an attribute of an object, which is called a domain. So, the values in the Weight column are selected from the set of all possible weights of children.
Each column has a name, which is usually written at the top of the table. These columns are called margins tables. When designing tables within a specific DBMS, it is possible to select for each field its a type, those. define for it a set of rules for displaying it, and also define those operations that can be performed on the data stored in this field. The sets of types may differ from DBMS to DBMS.
The field name must be unique in the table, however different tables can have fields with the same name. Any table must have at least one field; the fields are arranged in the table in accordance with the order of their names when it was created. Unlike fields, strings do not have names; their order in the table is not defined, and the number is not logically limited. The lines are called records tables.
Since the rows in the table are not ordered, it is impossible to select a row by its position - there is no "first", "second", "last" among them. Any table has one or more columns, the values of which uniquely identify each of its rows. Such a column (or combination of columns) is called a primary key. In the Sports Section table, the primary key is the Name column. (fig. 1.12).
Such a choice of the primary key has a significant drawback: it is impossible to write two children into the section with the same value of the full name field, which is not so rare in practice. That is why an artificial field is often introduced for numbering records in a table. Such a field, for example, could be a journal number for each child, which can ensure the uniqueness of each record in the table. If a table of a person satisfies this requirement, it is called attitude(relation).
Rice. 1.12. Relational data model
Relational data models can typically support four types of relationships between tables:
1) One to one(example: one table stores information about schoolchildren, the other contains information about schoolchildren's vaccinations).
2) One to Many(example: one table stores information about teachers, the other contains information about students who have these teachers as class teachers).
3) Many to One(as an example, we can offer the previous case, considering it from the other side, namely from the side of the table, which stores information about the students).
4) Many to many(example: one table stores orders for the supply of goods, and the other stores the firms that fulfill these orders, and several firms can be combined to fulfill one order /
Relational data presentation has a number of advantages. It is understandable to a user who is not a specialist in the field of programming, allows you to easily add new descriptions of objects and their characteristics, and has great flexibility in processing requests.
Questions and tasks
1. Give a definition to the concept of "data".
2. What is called the data life cycle?
3. What data models do you know?
4. Indicate the advantages and disadvantages of each data model.
INFORMATION PROCESSES
Data is a collection of information that is recorded on any medium - paper, disk, film. This information must be in a form suitable for storage, transmission and processing. Further transformation of the data provides information. Thus, information can be called the result of data analysis and transformation. The database stores various data, and the control system can issue the required information at a specific request. For example, you can find out from the school database which of the students lives on a certain street or who has not received a bad grade during the year, etc. Data is turned into information when they are interested. It can be argued that information is data used.
The word "information" comes from the Latin informatio, "information, presentation, explanation." Information is also called information about objects, environmental phenomena, their properties, which reduce the degree of uncertainty, incompleteness of knowledge. As a result of the exchange of information, a more complete understanding of the subject is formed, the level of awareness increases.
Information does not exist in isolation, by itself. There is always a source that produces it and that perceives it. Any object - man, computer, animal, plant - acts as a source or receiver. Information is always intended for a specific object.
A person receives information from a variety of sources - when reading, listening to the radio, watching TV, when he touches an object, tastes food. Different people can perceive the same information in different ways.
Depending on the scope of use, there is scientific, technical, economic and other types of information. This is the most powerful means of influencing and on society as a whole. According to the well-known expression, whoever possesses the most information on any issue, he owns the world, that is, is in an advantageous position in comparison with others. In everyday life, the development of society, health and life of people depend on information.
Over the millennia, mankind has accumulated a tremendous amount of knowledge, which continues to grow. The amount of information these days doubles every two years. In any situation, even the most ordinary one, only relevant, complete, reliable and understandable information is effective. Only relevant, that is, timely information received can benefit people. It is important to know the weather forecast or hurricane warning the day before, and not on the same day.
