It has been suggested that operationalization be merged into this article or section. (Discuss)

An operational definition is a showing of something—such as a variable, term, or object—in terms of the specific process or set of validation tests used to determine its presence and quantity. Properties described in this manner must be publicly accessible so that persons other than the definer can independently measure or test for them at will. An operational definition is generally designed to model a conceptual definition. Image File history File links Mergefrom. ... Operationalization is the process of converting concepts into specific observable behaviors that a researcher can measure. ... In computer science and mathematics, a variable (pronounced ) (sometimes called an object or identifier in computer science) is a symbolic representation used to denote a quantity or expression. ... Terminology is the study of terms and their use — of words and compound words that are used in specific contexts. ... In philosophy, an object is a thing, an entity, or a being. ... Illustration of a physical process: a geyser in action. Process (lat. ... In the context of hardware and software systems, formal verification is the act of proving or disproving the correctness of intended algorithms underlying a system with respect to a certain formal specification or property, using formal methods of mathematics. ... A conceptual definition is an element of the scientific research process, in which a specific concept is defined as a measurable occurrence. ...

The most basic operational definition is a process for identification of an object by distinguishing it from its background of empirical experience. The binary version produces either the result that the object exists, or that it doesn't, in the experiential field to which it is applied. The classifier version results in discrimination between what is part of the object and what is not part of it. This is also discussed in terms of semantics and pattern recognition. The term background can have any of the following meanings: Background (computer software) refers to software that is running, but not being displayed. ... A classifier, in linguistics, is a word or morpheme used in some languages in certain contexts to indicate the word class of a noun. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... Pattern recognition is a field within the area of machine learning. ...

For example, the weight of an object may be operationally defined in terms of the specific steps of putting an object on a weighing scale. The weight is whatever results from following the measurement procedure, which can in principle be repeated by anyone. It is intentionally not defined in terms of some intrinsic or private essence. The operational definition of weight is just the result of what happens when the defined procedure is followed. In other words, what's being defined is how to measure weight for any arbitrary object, and only incidentally the weight of a given object. Digital kitchen scales. ... In philosophy, essentialism is the view, that, for any specific kind of entity it is at least theoretically possible to specify a finite list of characteristics —all of which any entity must have to belong to the group defined. ...

Operational definitions are also used to define system states in terms of a specific, publicly accessible process of preparation or validation testing, which is repeatable at will. For example, 100 degrees Celsius may be crudely defined by describing the process of heating water until it is observed to boil. An item like a brick, or even a photograph of a brick, may be defined in terms of how it can be made. Likewise, iron may be defined in terms of the results of testing or measuring it in particular ways.

One simple, every day illustration of an operational definition is defining a cake in terms of how it is prepared and baked (i.e., its recipe is an operational definition). Similarly, the saying, if it walks like a duck and quacks like a duck, it must be some kind of duck, may be regarded as involving a sort of measurement process or set of tests (see Duck test). The duck test is a specific form of inductive reasoning whereby one can infer the nature of an unknown based upon its outwardly visible traits. ...

Limitations

If a definition invokes an historical event, such as having weighed an object sometime in the past, it is no longer repeatable, so it fails to qualify as operational. Similarly, a specific brick cannot be operationally defined by the process of making it, because that process is historical. (But see the example of the constellation Virgo below for a discussion of how to avoid this difficulty.)

Operational definitions are inherently difficult — arguably, even impossible — to apply to mental entities, because these latter are generally understand to be accessible only to the individual who experiences them and are therefore not independently verifiable. According to this line of thinking, a person's mental image of a brick cannot be operationally defined because it cannot be measured from outside that person's mood. Philosopher Daniel Dennett has argued that first-person operationalism is possible and desirable, using the anthropological version of the scientific method to bring the mind fully into the third-person realm required by science. As part of the Multiple Drafts Model of consciousness, Dennett defines a process he calls heterophenomenology, by which the mental is defined operationally in terms of the observed behavior of the subject. Daniel Clement Dennett (born March 28, 1942 in Boston, Massachusetts) is a prominent American philosopher whose research centers on philosophy of mind, philosophy of science and philosophy of biology, particularly as those fields relate to evolutionary biology and cognitive science. ... Daniel Dennetts Multiple Drafts Theory or Model of Consciousness is a physical theory of consciousness based upon the proposal that the brain acts as an information processor. ... According to Dennett, heterophenomonology (phenomenology of another not oneself), is the process in which you take the vocal sounds emanating from the subjects’ mouths (and your own mouth) and interpret them! He goes on to assert that the total set of details of heterophenomenology, plus all the data we...

Usefulness

Despite the controversial philosophical origins of the concept, particularly its close association with logical positivism, operational definitions have undisputed practical applications. This is especially so in the social and medical sciences, where operational definitions of key terms are used to preserve the unambiguous empirical testability of hypothesis and theory. Operational definitions are also important in the physical sciences. Philosophy (from the Greek words philos and sophia meaning love of wisdom) is understood in different ways historically and by different philosophers. ... Logical positivism grew from the discussions of Moritz Schlicks Vienna Circle and Hans Reichenbachs Berlin Circle in the 1920s and 1930s. ... Physical science is the branch of science including chemistry and physics, usually contrasted with the social sciences and sometimes including and sometimes contrasted with natural or biological science. ...

Relevance to philosophy

The Stanford Encyclopedia of Philosophy says the following about Operationalism stored at http://plato.stanford.edu/entries/scientific-realism/ and written by Richard Boyd: Richard Boyd is a philosopher currently housed at Cornell University. ...

The idea originally arises in the operationalist philosophy of P. W. Bridgman and others. By 1914, Bridgman was dismayed by the abstraction and lack of clarity with which, he argued, many scientific concepts were expressed. Inspired by logical positivism and the phenomenalism of Ernst Mach, in 1914 he declared that the meaning of a theoretical term (or unobversable entity), such as electron density, lay in the operations, physical and mental, performed in its measurement. The goal was to eliminate all reference to theoretical entities by "rationally reconstructing" them in terms of the particular operations of laboratory procedures and experimentation. For other uses, see Philosophy (disambiguation). ... Percy Williams Bridgman (April 21, 1882–August 20, 1961) was an American physicist who won the 1946 Nobel Prize in Physics for his work on the physics of high pressures. ... Year 1914 (MCMXIV) was a common year starting on Thursday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Wednesday of the 13-day-slower Julian calendar). ... Logical positivism grew from the discussions of Moritz Schlicks Vienna Circle and Hans Reichenbachs Berlin Circle in the 1920s and 1930s. ... In epistemology and the philosophy of perception, phenomenalism is the view that physical objects do not exist as things in themselves but only as perceptual phenomena or sensory stimuli (e. ... Ernst Mach Ernst Mach (February 18, 1838 – February 19, 1916) was an Austrian-Czech physicist and philosopher and is the namesake for the Mach number and the optical illusion known as Mach bands. ... Year 1914 (MCMXIV) was a common year starting on Thursday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Wednesday of the 13-day-slower Julian calendar). ...

Hence, the term electron density could be analyzed into a statement of the following form:

(*) The electron density of an object, O, is given by the value, x, if and only if P applied to O yields the value x,

where P stands for an instrument that scientists take as a procedure for measuring electron density.

Operationalism, defined in this way, was rejected even by the logical positivists, due to inherent problems: defining terms operationally necessarily implied the analytic necessity of the definition. The analyticity of operational definitions like (*) is essential to the project of rational reconstruction. Operationalism is not, for example, the idea that electron density is defined as whatever magnitude instruments of the sort P reliably measure. On that conception (*) would represent an empirical discovery about how to measure electron density, but -- since electrons are unobservables -- that's a realist conception not an empiricist one. What the project of rational reconstruction requires is that (*) be true purely as a matter of linguistic stipulation about how the term "electron density" is to be used. Scientific realism is a view in the philosophy of science about the nature of scientific success, an answer to the question what does the success of science involve? The debate over what the success of science involves centers primarily on the status of unobservable entities (objects, process and events) apparently... In philosophy generally, empiricism is a theory of knowledge emphasizing the role of experience, especially sensory perception, in the formation of ideas, while discounting the notion of innate ideas. ...

Since (*) is supposed to be analytic, it's supposed to be unrevisable. There is supposed to be no such thing as discovering, about P, that some other instrument provides a more accurate value for electron density, or provides values for electron density under conditions where P doesn't function. Here again, thinking that there could be such an improvement in P with respect to electron density requires thinking of electron density as a real feature of the world which P (perhaps only approximately) measures. But that's the realist conception that operationalism is designed rationally to do away with!

In actual, and apparently reliable, scientific practice, changes in the instrumentation associated with theoretical terms are routine, and apparently crucial to the progress of science. According to a 'pure' operationalist conception, these sorts of modifications would not be methodologically acceptable, since each definition must be considered to identify a unique 'object' (or class of objects). In practice, however, an 'operationally defined' object is often taken to be that object which is determined by a constellation of different unique 'operational procedures.'

Most logical empiricists were not willing to accept the conclusion that operational definitions must be unique (in contradiction to 'established' scientific practice). So they felt compelled to reject operationalism. [[In the end, it reduces to a reductio ad absurdem, since each measuring instrument must itself be operationally defined, in infinite regress... But this was also a failure of the logical positivist approach generally.]]

However, this rejection of operationalism as a general project destined ultimately to define all experiential phenomena uniquely did not mean that operational definitions ceased to have any practical use or that they could not be applied in particular cases.

Relevance to science

Operational definitions are at their most controversial in the field of psychology, where intuitive concepts, such as intelligence need to be operationally defined before they become amenable to scientific investigation, for example, through processes such as IQ tests. Such definitions are used as a follow up to a conceptual definition, in which the specific concept is defined as a measurable occurrence. John Stuart Mill pointed out the dangers of believing that anything that could be given a name must refer to a thing and Stephen Jay Gould and others have criticized psychologists for doing just that. A committed operationalist would respond that speculation about the thing in itself, or noumenon, should be resisted as meaningless, and would comment only on phenomena using operationally defined terms and tables of operationally defined measurements. Psychological science redirects here. ... Intelligence is the mental capacity to reason, plan, solve problems, think abstractly, comprehend ideas and language, and learn. ... ... A conceptual definition is an element of the scientific research process, in which a specific concept is defined as a measurable occurrence. ... John Stuart Mill (20 May 1806 – 8 May 1873), British philosopher, political economist, civil servant and Member of Parliament, was an influential liberal thinker of the 19th century. ... Stephen Jay Gould (September 10, 1941 – May 20, 2002) was an American paleontologist, evolutionary biologist, and historian of science. ... A psychologist is a researcher and/or a practitioner of psychology. ... The noumenon (plural: noumena) classically refers to an object of human inquiry, understanding or cognition. ... A phenomenon (plural: phenomena) is an observable event, especially something special (literally something that can be seen from the Greek word phainomenon = observable). ...

A behaviorist psychologist might (operationally) define intelligence as that score obtained on a specific IQ test (e.g., the Wechsler Adult Intelligence Scale test) by a human subject. The theoretical underpinnings of the WAIS would be completely ignored. This WAIS measurement would only be useful to the extent it could be shown to be related to other operationally defined measurements, e.g., to the measured probability of graduation from university. [1] Behaviorism (also called learning perspective) is a philosophy of psychology based on the proposition that all things which organisms do — including acting, thinking and feeling—can and should be regarded as behaviors. ... Wechsler Adult Intelligence Scale or WAIS is a general test of intelligence (IQ), published in February 1955 as a revision of the Wechsler-Bellevue test (1939), standardised for use with adults over the age of 16. ...

Relevance to business

On October 15, 1970, the West Gate Bridge in Melbourne, Australia collapsed, killing 35 construction workers. The subsequent enquiry found that the failure arose because engineers had specified the supply of a quantity of flat steel plate. The word flat in this context lacked an operational definition, so there was no test for accepting or rejecting a particular shipment or for controlling quality. is the 288th day of the year (289th in leap years) in the Gregorian calendar. ... Year 1970 (MCMLXX) was a common year starting on Thursday (link shows full calendar) of the Gregorian calendar. ... The West Gate Bridge is a large cable-stayed bridge in Melbourne, Victoria, Australia. ... This article is about the Australian city; the name may also refer to City of Melbourne or Melbourne city centre. ...

In his managerial and statistical writings, W. Edwards Deming placed great importance on the value of using operational definitions in all agreements in business. As he said: William Edwards Deming (October 14, 1900–December 20, 1993) was an American statistician, college professor, author, lecturer, and consultant. ...

"An operational definition is a procedure agreed upon for translation of a concept into measurement of some kind." - W. Edwards Deming

"There is no true value of any characteristic, state, or condition that is defined in terms of measurement or observation. Change of procedure for measurement (change of operational definition) or observation produces a new number." - W. Edwards Deming

Relevance to process

Operational, in a process context, also can denote a working method or a philosophy that focuses principally on cause and effect relationships (or stimulus/response, behavior, ...) of specific interest to a particular domain at a particular point in time. As a working method, it does not consider issues related to a domain that are more general, such as the ontological, etc. This article is about the philosophical meaning of ontology. ...

The term can be used strictly within the realm of the interactions of humans with advanced computational systems. In this sense, an AI system cannot be entirely operational (this issue can be used to discuss strong versus weak AI) if learning is involved. // This disambiguation page covers alternative uses of the terms Ai, AI, and A.I. Ai (as a word, proper noun and set of initials) can refer to many things. ...

Given that one motive for the operational approach is stability, systems that relax the operational factor can be problematic, for several reasons, as the operational is a means to manage complexity. There will be differences in the nature of the operational as it pertains to degrees along the end-user computing axis. End User Computing (EUC) is a group of approaches to computing that aim at better integrating end users into the computing environment or that attempt to realize the potential for high-end computing to perform in a trustworthy manner in problem solving of the highest order. ...

For instance, a Knowledge Based Engineering system can enhance its operational aspect and thereby its stability through more involvement by the SME, of course, thereby opening up issues of limits that are related to being human, in the sense that, many times, computational results have to be taken at face value due to several factors (hence the Duck test's necessity arises) that even an expert cannot overcome. The end proof may be the final results (reasonable facsimile by simulation or artifact, working design, etc.) that are not guaranteed to be repeatable, may have been costly to attain (time and money), and so forth. Knowledge-based engineering (KBE) is a discipline with roots in computer-aided design (CAD) and knowledge-based systems but has several definitions and roles depending upon the context. ... SME may stand for: Social Market Economy Small and medium enterprise(s), a synonym for Small and Medium-sized Business(es) (SMB) Spontaneous Music Ensemble Subject Matter Expert Structure Mapping Engine, analogy-based AI technology by Ken Forbus based on Dedre Gentners structure-mapping theory Sony Music Entertainment, a... A limit can be: Limit (mathematics), including: Limit of a function Limit of a sequence Net (topology) Limit (category theory) A constraint (mathematical, physical, economical, legal, etc. ... This article is about modern humans. ... The duck test is a specific form of inductive reasoning whereby one can infer the nature of an unknown based upon its outwardly visible traits. ... This article is about the general term. ... Look up artifact in Wiktionary, the free dictionary. ...

Many domains, with a numerics focus, use limits logic to overcome the Duck test necessity with varying degrees of success. Complex situations may require logic to be more non-monotonic than not raising concerns related to the qualification, frame, and ramification problems. Numerical analysis is the study of approximate methods for the problems of continuous mathematics (as distinguished from discrete mathematics). ... A limit can be: Limit (mathematics), including: Limit of a function Limit of a sequence Net (topology) Limit (category theory) A constraint (mathematical, physical, economical, legal, etc. ... The duck test is a specific form of inductive reasoning whereby one can infer the nature of an unknown based upon its outwardly visible traits. ... A non-monotonic logic is a formal logic whose consequence relation is not monotonic. ... In philosophy and AI, the qualification problem is concerned with the impossibility of listing all the preconditions required for a real-world action to have its intended effect. ... In artificial intelligence, the frame problem has a number of possible formulations. ... The ramification problem is concerned with indirect consequences of an action. ...

Examples

Temperature

The thermodynamic definition of temperature, due to Nicolas Léonard Sadi Carnot, refers to heat "flowing" between "infinite reservoirs". This is all highly abstract and unsuited for the day-to-day world of science and trade. In order to make the idea concrete, temperature is defined in terms of operations with the gas thermometer. However, these are sophisticated and delicate instruments, only adapted to the national standardization laboratory. For other uses, see Temperature (disambiguation). ... Sadi Carnot in the dress uniform of a student of the École polytechnique Nicolas Léonard Sadi Carnot (June 1, 1796 - August 24, 1832) was a French physicist and military engineer who gave the first successful theoretical account of heat engines, now known as the Carnot cycle, thereby laying the...

For day-to-day use, the International Practical Temperature Scale (IPTS) is used, defining temperature in terms of the electrical resistance of a thermistor, with specified construction, calibrated against operationally defined fixed points. Electrical resistance is a measure of the degree to which an electrical component opposes the passage of current. ... NTC thermistor, bead type, insulated wires Thermistor symbol A thermistor is a type of resistor used to measure temperature changes, relying on the change in its resistance with changing temperature. ...

Electric current

Electric current is defined in terms of the force between two infinite parallel conductors, separated by a specified distance. This definition is too abstract for practical measurement, so a device known as a current balance is used to define the ampere operationally. Electric current is the flow (movement) of electric charge. ... For other uses, see Force (disambiguation). ... For other uses, see Infinity (disambiguation). ... Parallel is a term in geometry and in everyday life that refers to a property in Euclidean space of two or more lines or planes, or a combination of these. ... The ampere balance (also current balance or Kelvin balance) is an electromechanical apparatus used for the precise measurement of the SI unit of electric current, the ampere. ... For other uses, see Ampere (disambiguation). ...

Mechanical hardness

Unlike temperature and electric current, there is no abstract physical concept of the hardness of a material. It is a slightly vague, subjective idea, somewhat like the idea of intelligence. In fact, it leads to three more specific ideas: For other uses, see Temperature (disambiguation). ... Electric current is the flow (movement) of electric charge. ... Look up hardness in Wiktionary, the free dictionary. ... Intelligence is the mental capacity to reason, plan, solve problems, think abstractly, comprehend ideas and language, and learn. ...

1. Scratch hardness measured on Mohs' scale;
2. Indentation hardness; and
3. Rebound, or dynamic, hardness measured with a Shore scleroscope.

Of these, indentation hardness itself leads to many operational definitions, the most important of which are: The Mohs scale of mineral hardness characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer material. ...

1. Brinell hardness test—using a 10 mm steel ball;
2. Vickers hardness test—using a pyramidal diamond indenter; and
3. Rockwell hardness test—using a diamond cone indenter.

In all these, a process is defined for loading the indenter, measuring the resulting indentation and calculating a hardness number. Each of these three sequences of measurement operations produces numbers that are consistent with our subjective idea of hardness. The harder the material to our informal perception, the greater the number it will achieve on our respective hardness scales. Furthermore, experimental results obtained using these measurement methods has shown that the hardness number can be used to predict the stress required to permanently deform steel, a characteristic that fits in well with our idea of resistance to permanent deformation. However, there is not always a simple relationship between the various hardness scales. Vickers and Rockwell hardness numbers exhibit qualitatively different behaviour when used to describe some materials and phenomena. The Brinell scale characterises the indentation hardness of materials through the scale of penetration of an indenter, loaded on a material test-piece. ... A Vickers hardness tester The Vickers hardness test was developed in the early 1920s as an alternative method to measure the hardness of materials. ... The Rockwell scale characterises the indentation hardness of materials through the depth of penetration of an indenter, loaded on a material sample and compared to the penetration in some reference material. ...

The constellation Virgo

The constellation Virgo is a specific constellation of stars in the sky, hence the process of forming Virgo cannot be an operational definition, since it is historical and not repeatable. Nevertheless, the process whereby we locate Virgo in the sky is repeatable, so in this way, Virgo is operatonally defined. In fact, Virgo can have any number of definitions (although we can never prove that we are talking about the same Virgo), and any number may be operational.

Duck typing

In advanced modeling, with the requisite computational support such as KBE, mappings must be maintained between a real-world object, its abstracted counterparts as defined by the domain and its experts, and the computer models. Mismatches between domain models and their computational mirrors can raise issues that are apropos to this topic. Techniques that allow the flexible modeling required for many hard problems must resolve issues of identity, type, etc. which then lead to methods, such as Duck typing. Knowledge-based engineering (KBE) is a discipline with roots in computer-aided design (CAD) and knowledge-based systems but has several definitions and roles depending upon the context. ... Duck typing is a style of dynamic typing in which an objects current set of methods and properties determines the valid semantics, rather than its inheritance from a particular class. ...

Conceptual vs operational definition

For other uses, see Newton (disambiguation). ... Spring scale. ...

References

• Ballantyne, Paul F. History and Theory of Psychology Course, in Langfeld, H.S. (1945) Introduction to the Symposium on Operationism. Psyc. Rev. 32, 241-243.[2]
• Bohm, D. (1996). On dialog. N.Y.: Routledge.
• Boyd, Richard. On the Current Status of the Issue of Scientific Realism in Erkenntnis. 19: 45-90.
• Bridgman, P. W. The way things are. Cambridge: Harvard University Press. (1959)
• Carnap, R. The Elimination of Metaphysics Through Logical Analysis of Language in Ayer, A.J. 1959.
• Churchland, Patricia, Neurophilosophy— Toward a unified science of the mind/brain, MIT Press (1986).
• Churchland, Paul., A Neurocomputational Perspective— The Nature of Mind and the Structure of Science, MIT Press (1989).
• Dennett, Daniel C. Consciousness Explained, Little, Brown & Co.. 1992.
• Depraz, N. (1999). "The phenomenological reduction as praxis." Journal of Consciousness Studies, 6(2-3), 95-110.
• Hardcastle, G. L. (1995). "S.S. Stevens and the origins of operationism." Philosophy of Science, 62, 404-424.
• Hermans, H. J. M. (1996). "Voicing the self: from information processing to dialogical interchange." Psychological Bulletin, 119(1), 31-50.
• Hyman, Bronwen, U of Toronto, and Shephard, Alfred H., U of Manitoba, "Zeitgeist: The Development of an Operational Definition", The Journal of Mind and Behavior, 1(2), pps. 227-246 (1980)
• Leahy, Thomas H., Virginia Commonwealth U, The Myth of Operationism, ibid, pps. 127-144 (1980)
• Ribes-Inesta, Emilio "What Is Defined In Operational Definitions? The Case Of Operant Psychology," Behavior and Philosophy, 2003.[3]
• Roepstorff, A. & Jack, A. (2003). "Editorial introduction, Special Issue: Trusting the Subject? (Part 1)." Journal of Consciousness Studies, 10(9-10), v-xx.
• Roepstorff, A. & Jack, A. (2004). "Trust or Interaction? Editorial introduction, Special Issue: Trusting the Subject? (Part 2)." Journal of Consciousness Studies, 11(7-8), v-xxii.
• Stevens, S. S. Operationism and logical positivism, in M. H. Marx (Ed.), Theories in contemporary psychology (pp. 47-76). New York: MacMillan. (1963)
• Thomson — Waddsworth, eds., Learning Psychology: Operational Definitions Research Methods Workshops[4]

See also

• Pragmatic maxim
• Pragmaticism
• Pragmatism