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http://www.sergovic-ellis.com/Staff スタッフEmployment is a contract between two parties, one being the employer and the other being the employee. An employee may be defined as: "A person in the service of another under any contract of hire, express or implied, oral or written, where the employer has the power or right to control and direct the employee in the material details of how the work is to be performed." Black's Law Dictionary page 471 (5th ed. 1979).
In a commercial setting, the employer conceives of a productive activity, generally with the intention of generating a profit, and the employee contributes labour to the enterprise, usually in return for payment of wages. Employment also exists in the public, non-profit and household sectors. To the extent that employment or the economic equivalent is not universal, unemployment exists.
An employer is a person or institution that hires employees or workers. Employers offer hourly wages or a salary in exchange for the worker's labor power, depending upon whether the employee is paid by the hour or a set rate per pay period. A salaried employee is typically not paid more for more hours worked than the minimum, whereas wages are paid for all hours worked, including overtime.
Employers include everything from individuals hiring a babysitter to governments and businesses which may hire many thousands of employees. In most western societies, governments are the largest single employers but most of the work force is employed in small and medium businesses in the private sector.
Although employees may contribute to an enterprise, the employer maintains control over the productive base of land and capital, and is the entity named in contracts. The employer typically maintains ownership of intellectual property created by an employee within the scope of employment and as a function thereof. These inventions or creations become the property of the employer based on a concept known as "works for hire".
An employers’ relative level of power over employees is dependent upon numerous factors; the most influential being the nature of the employment relationship. The relationship employers share with employees is affected by three significant factors ? interests, control and motivation. It is up to employers to effectively manage and balance these factors to ensure a harmonious and productive working relationship.
Interests can be best described as monetary constraints and economic pressures placed on organizations in their pursuit of profits. It covers facets such as labour productivity, wages and the effect of financial markets on businesses.
Wood et al (2004, p 355) describe control as being either output focused, focusing on desired targets with managers defining, and using, their own methods for reaching targets, or process controls, which specify the manner in which tasks will be achieved (Ibid, p. 357). Employer and managerial control within an organization rests at many levels and has important implications for staff and productivity alike, with control forming the fundamental link between desired outcomes and actual processes. Employers must balance interests such as decreasing wage constraints with a maximization of labour productivity in order to achieve a profitable and productive employment relationship.
Motivation is the third and most difficult of the factors for employers to effectively manage in the employment relationship . Employee motivation can often be in direct conflict with control mechanisms of employers, and can be broadly defined as that which energizes, directs and sustains human behaviour ( Stone, 2005, p 412). Dubin (1958, p 213) further elaborates on this, noting motivation as “something that moves a person to action, and continues him in the course of action already initiated.”
The employment relationship is thus a difficult challenge for employers to manage, as all three facets are often in direct competition with each other, with interests, control and motivation often clashing in the equally important quest for individual employee autonomy, employer command and control and ultimate profits.
information 情報Information theory is a branch of applied mathematics and electrical engineering involving the quantification of information. Historically, information theory was developed to find fundamental limits on compressing and reliably communicating data. Since its inception it has broadened to find applications in many other areas, including statistical inference, natural language processing, cryptography generally, networks other than communication networks -- as in neurobiology, the evolution and function of molecular codes, model selection in ecology, thermal physics, quantum computing, plagiarism detection and other forms of data analysis.[
A key measure of information in the theory is known as information entropy, which is usually expressed by the average number of bits needed for storage or communication. Intuitively, entropy quantifies the uncertainty involved when encountering a random variable. For example, a fair coin flip (2 equally likely outcomes) will have less entropy than a roll of a die (6 equally likely outcomes).
Applications of fundamental topics of information theory include lossless data compression (e.g. ZIP files), lossy data compression (e.g. MP3s), and channel coding (e.g. for DSL lines). The field is at the intersection of mathematics, statistics, computer science, physics, neurobiology, and electrical engineering. Its impact has been crucial to the success of the Voyager missions to deep space, the invention of the CD, the feasibility of mobile phones, the development of the Internet, the study of linguistics and of human perception, the understanding of black holes, and numerous other fields. Important sub-fields of information theory are source coding, channel coding, algorithmic complexity theory, algorithmic information theory, and measures of information.
The main concepts of information theory can be grasped by considering the most widespread means of human communication: language. Two important aspects of a good language are as follows: First, the most common words (e.g., "a", "the", "I") should be shorter than less common words (e.g., "benefit", "generation", "mediocre"), so that sentences will not be too long. Such a tradeoff in word length is analogous to data compression and is the essential aspect of source coding. Second, if part of a sentence is unheard or misheard due to noise ? e.g., a passing car ? the listener should still be able to glean the meaning of the underlying message. Such robustness is as essential for an electronic communication system as it is for a language; properly building such robustness into communications is done by channel coding. Source coding and channel coding are the fundamental concerns of information theory.
Note that these concerns have nothing to do with the importance of messages. For example, a platitude such as "Thank you; come again" takes about as long to say or write as the urgent plea, "Call an ambulance!" while clearly the latter is more important and more meaningful. Information theory, however, does not consider message importance or meaning, as these are matters of the quality of data rather than the quantity and readability of data, the latter of which is determined solely by probabilities.
Information theory is generally considered to have been founded in 1948 by Claude Shannon in his seminal work, "A Mathematical Theory of Communication." The central paradigm of classical information theory is the engineering problem of the transmission of information over a noisy channel. The most fundamental results of this theory are Shannon's source coding theorem, which establishes that, on average, the number of bits needed to represent the result of an uncertain event is given by its entropy; and Shannon's noisy-channel coding theorem, which states that reliable communication is possible over noisy channels provided that the rate of communication is below a certain threshold called the channel capacity. The channel capacity can be approached in practice by using appropriate encoding and decoding systems.
Information theory is closely associated with a collection of pure and applied disciplines that have been investigated and reduced to engineering practice under a variety of rubrics throughout the world over the past half century or more: adaptive systems, anticipatory systems, artificial intelligence, complex systems, complexity science, cybernetics, informatics, machine learning, along with systems sciences of many descriptions. Information theory is a broad and deep mathematical theory, with equally broad and deep applications, amongst which is the vital field of coding theory.
Coding theory is concerned with finding explicit methods, called codes, of increasing the efficiency and reducing the net error rate of data communication over a noisy channel to near the limit that Shannon proved is the maximum possible for that channel. These codes can be roughly subdivided into data compression (source coding) and error-correction (channel coding) techniques. In the latter case, it took many years to find the methods Shannon's work proved were possible. A third class of information theory codes are cryptographic algorithms (both codes and ciphers). Concepts, methods and results from coding theory and information theory are widely used in cryptography and cryptanalysis. See the article ban (information) for a historical application.
Information theory is also used in information retrieval, intelligence gathering, gambling, statistics, and even in musical composition. from wikipedia |