Utility

Within economics the concept of utility is used to model worth or value, but its usage has evolved significantly over time. The term was introduced initially as a measure of pleasure or satisfaction within the theory of utilitarianism by moral philosophers such as Jeremy Bentham and John Stuart Mill. But the term has been adapted and reapplied within neoclassical economics, which dominates modern economic theory, as a utility function that represents a consumer's preference ordering over a choice set. As such, it is devoid of its original interpretation as a measurement of the pleasure or satisfaction obtained by the consumer from that choice.

Utility function

Consider a set of alternatives facing an individual, and over which the individual has a preference ordering. A utility function is able to represent those preferences if it is possible to assign a real number to each alternative, in such a way that alternative a is assigned a number greater than alternative b if, and only if, the individual prefers alternative a to alternative b. In this situation an individual that selects the most preferred alternative available is necessarily also selecting the alternative that maximises the associated utility function. In general economic terms, a utility function measures preferences concerning a set of goods and services. Often, utility is correlated with words such as happiness, satisfaction, and welfare, and these are hard to measure mathematically. Thus, economists utilize consumption baskets of preferences in order to measure these abstract, non quantifiable ideas.

Gérard Debreu precisely defined the conditions required for a preference ordering to be representable by a utility function.[1] For a finite set of alternatives these require only that the preference ordering is complete (so the individual is able to determine which of any two alternatives is preferred, or that they are equally preferred), and that the preference order is transitive.

Applications

Utility is usually applied by economists in such constructs as the indifference curve, which plot the combination of commodities that an individual or a society would accept to maintain a given level of satisfaction. Utility and indifference curves are used by economists to understand the underpinnings of demand curves, which are half of the supply and demand analysis that is used to analyze the workings of goods markets.

Individual utility and social utility can be construed as the value of a utility function and a social welfare function respectively. When coupled with production or commodity constraints, under some assumptions these functions can be used to analyze Pareto efficiency, such as illustrated by Edgeworth boxes in contract curves. Such efficiency is a central concept in welfare economics.

In finance, utility is applied to generate an individual's price for an asset called the indifference price. Utility functions are also related to risk measures, with the most common example being the entropic risk measure.

In the field of artificial intelligence, utility functions are used to convey the value of various outcomes to intelligent agents. This allows the agents to plan actions with the goal of maximizing the utility (or "value") of available choices.

Revealed preference

It was recognized that utility could not be measured or observed directly, so instead economists devised a way to infer underlying relative utilities from observed choice. These 'revealed preferences', as they were named by Paul Samuelson, were revealed e.g. in people's willingness to pay:

Utility is taken to be correlative to Desire or Want. It has been already argued that desires cannot be measured directly, but only indirectly, by the outward phenomena to which they give rise: and that in those cases with which economics is chiefly concerned the measure is found in the price which a person is willing to pay for the fulfillment or satisfaction of his desire.[2]:78

Functions

There has been some controversy over the question whether the utility of a commodity can be measured or not. At one time, it was assumed that the consumer was able to say exactly how much utility he got from the commodity. The economists who made this assumption belonged to the 'cardinalist school' of economics. Today utility functions, expressing utility as a function of the amounts of the various goods consumed, are treated as either cardinal or ordinal, depending on whether they are or are not interpreted as providing more information than simply the rank ordering of preferences over bundles of goods, such as information on the strength of preferences.

Cardinal

When cardinal utility is used, the magnitude of utility differences is treated as an ethically or behaviorally significant quantity. For example, suppose a cup of orange juice has utility of 120 utils, a cup of tea has a utility of 80 utils, and a cup of water has a utility of 40 utils. With cardinal utility, it can be concluded that the cup of orange juice is better than the cup of tea by exactly the same amount by which the cup of tea is better than the cup of water. Formally speaking, this means that if one has a cup of tea, she would be willing to take any bet with a probability, p, greater than .5 of getting a cup of juice, with a risk of getting a cup of water equal to 1-p. One cannot conclude, however, that the cup of tea is two thirds as good as the cup of juice, because this conclusion would depend not only on magnitudes of utility differences, but also on the "zero" of utility. For example, if the "zero" of utility was located at -40, then a cup of orange juice would be 160 utils more than zero, a cup of tea 120 utils more than zero. Cardinal utility, to economics, can be seen as the assumption that utility can be measured through quantifiable characteristics, such as height, weight, temperature, etc.

Neoclassical economics has largely retreated from using cardinal utility functions as the basis of economic behavior. A notable exception is in the context of analyzing choice under conditions of risk (see below).

Sometimes cardinal utility is used to aggregate utilities across persons, to create a social welfare function.

Ordinal

When ordinal utilities are used, differences in utils (values taken on by the utility function) are treated as ethically or behaviorally meaningless: the utility index encodes a full behavioral ordering between members of a choice set, but tells nothing about the related strength of preferences. In the above example, it would only be possible to say that juice is preferred to tea to water, but no more. Thus, ordinal utility utilizes comparisons, such as "preferred to", "no more", "less than", etc.

Ordinal utility functions are unique up to increasing monotone (or monotonic) transformations. For example, if a function is taken as ordinal, it is equivalent to the function , because taking the 3rd power is an increasing monotone transformation (or monotonic transformation). This means that the ordinal preference induced by these functions is the same (although they are two different functions). In contrast, cardinal utilities are unique only up to increasing linear transformations, so if is taken as cardinal, it is not equivalent to .

Preferences

Although preferences are the conventional foundation of microeconomics, it is often convenient to represent preferences with a utility function and analyze human behavior indirectly with utility functions. Let X be the consumption set, the set of all mutually-exclusive baskets the consumer could conceivably consume. The consumer's utility function ranks each package in the consumption set. If the consumer strictly prefers x to y or is indifferent between them, then .

For example, suppose a consumer's consumption set is X = {nothing, 1 apple,1 orange, 1 apple and 1 orange, 2 apples, 2 oranges}, and its utility function is u(nothing) = 0, u(1 apple) = 1, u(1 orange) = 2, u(1 apple and 1 orange) = 4, u(2 apples) = 2 and u(2 oranges) = 3. Then this consumer prefers 1 orange to 1 apple, but prefers one of each to 2 oranges.

In micro-economic models, there are usually a finite set of L commodities, and a consumer may consume an arbitrary amount of each commodity. This gives a consumption set of , and each package is a vector containing the amounts of each commodity. In the previous example, we might say there are two commodities: apples and oranges. If we say apples is the first commodity, and oranges the second, then the consumption set and u(0, 0) = 0, u(1, 0) = 1, u(0, 1) = 2, u(1, 1) = 4, u(2, 0) = 2, u(0, 2) = 3 as before. Note that for u to be a utility function on X, it must be defined for every package in X.

A utility function represents a preference relation on X iff for every , implies . If u represents , then this implies is complete and transitive, and hence rational.

Revealed preferences in finance

In financial applications, e.g. portfolio optimization, an investor chooses financial portfolio which maximizes his/her own utility function, or, equivalently, minimizes his/her risk measure. For example, modern portfolio theory selects variance as a measure of risk; other popular theories are expected utility theory[3] and prospect theory.[4] To determine specific utility function for any given investor, one could design a questionnaire procedure with questions in the form: How much would you pay for x% chance of getting y? Revealed preference theory suggests a more direct approach: observe a portfolio X* which an investor currently holds, and then find a utility function/risk measure such that X* becomes an optimal portfolio.[5]

Examples

In order to simplify calculations, various alternative assumptions have been made concerning details of human preferences, and these imply various alternative utility functions such as:

Most utility functions used in modeling or theory are well-behaved. They are usually monotonic and quasi-concave. However, it is possible for preferences not to be representable by a utility function. An example is lexicographic preferences which are not continuous and cannot be represented by a continuous utility function.[6]

Expected utility

The expected utility theory deals with the analysis of choices among risky projects with multiple (possibly multidimensional) outcomes.

The St. Petersburg paradox was first proposed by Nicholas Bernoulli in 1713 and solved by Daniel Bernoulli in 1738. D. Bernoulli argued that the paradox could be resolved if decision-makers displayed risk aversion and argued for a logarithmic cardinal utility function. (Analyses of international survey data in the 21st century have shown that insofar as utility represents happiness, as in utilitarianism, it is indeed proportional to log income.)

The first important use of the expected utility theory was that of John von Neumann and Oskar Morgenstern, who used the assumption of expected utility maximization in their formulation of game theory.

von Neumann–Morgenstern

Von Neumann and Morgenstern addressed situations in which the outcomes of choices are not known with certainty, but have probabilities attached to them.

A notation for a lottery is as follows: if options A and B have probability p and 1 − p in the lottery, we write it as a linear combination:

More generally, for a lottery with many possible options:

where .

By making some reasonable assumptions about the way choices behave, von Neumann and Morgenstern showed that if an agent can choose between the lotteries, then this agent has a utility function such that the desirability of an arbitrary lottery can be calculated as a linear combination of the utilities of its parts, with the weights being their probabilities of occurring.

This is called the expected utility theorem. The required assumptions are four axioms about the properties of the agent's preference relation over 'simple lotteries', which are lotteries with just two options. Writing to mean 'A is weakly preferred to B' ('A is preferred at least as much as B'), the axioms are:

  1. completeness: For any two simple lotteries and , either or (or both, in which case they are viewed as equally desirable).
  2. transitivity: for any three lotteries , if and , then .
  3. convexity/continuity (Archimedean property): If , then there is a between 0 and 1 such that the lottery is equally desirable as .
  4. independence: for any three lotteries and any probability p, if and only if . Intuitively, if the lottery formed by the probabilistic combination of and is no more preferable than the lottery formed by the same probabilistic combination of and then and only then .

Axioms 3 and 4 enable us to decide about the relative utilities of two assets or lotteries.

In more formal language: A von Neumann–Morgenstern utility function is a function from choices to the real numbers:

which assigns a real number to every outcome in a way that captures the agent's preferences over simple lotteries. Under the four assumptions mentioned above, the agent will prefer a lottery to a lottery if and only if, for the utility function characterizing that agent, the expected utility of is greater than the expected utility of :

.

Of all the axioms, independence is the most often discarded. A variety of generalized expected utility theories have arisen, most of which drop or relax the independence axiom.

As probability of success

Castagnoli and LiCalzi and Bordley and LiCalzi (2000) provided another interpretation for Von Neumann and Morgenstern's theory. Specifically for any utility function, there exists a hypothetical reference lottery with the expected utility of an arbitrary lottery being its probability of performing no worse than the reference lottery. Suppose success is defined as getting an outcome no worse than the outcome of the reference lottery. Then this mathematical equivalence means that maximizing expected utility is equivalent to maximizing the probability of success. In many contexts, this makes the concept of utility easier to justify and to apply. For example, a firm's utility might be the probability of meeting uncertain future customer expectations.[7][8][9][10]

Indirect utility

An indirect utility function gives the optimal attainable value of a given utility function, which depends on the prices of the goods and the income or wealth level that the individual possesses.

Money

One use of the indirect utility concept is the notion of the utility of money. The (indirect) utility function for money is a nonlinear function that is bounded and asymmetric about the origin. The utility function is concave in the positive region, reflecting the phenomenon of diminishing marginal utility. The boundedness reflects the fact that beyond a certain point money ceases being useful at all, as the size of any economy at any point in time is itself bounded. The asymmetry about the origin reflects the fact that gaining and losing money can have radically different implications both for individuals and businesses. The non-linearity of the utility function for money has profound implications in decision making processes: in situations where outcomes of choices influence utility through gains or losses of money, which are the norm in most business settings, the optimal choice for a given decision depends on the possible outcomes of all other decisions in the same time-period.[11]

Discussion and criticism

Cambridge economist Joan Robinson famously criticized utility for being a circular concept: "Utility is the quality in commodities that makes individuals want to buy them, and the fact that individuals want to buy commodities shows that they have utility"[12]:48 Robinson also pointed out that because the theory assumes that preferences are fixed this means that utility is not a testable assumption. This is so because if we take changes in peoples' behavior in relation to a change in prices or a change in the underlying budget constraint we can never be sure to what extent the change in behavior was due to the change in price or budget constraint and how much was due to a change in preferences.[13] This criticism is similar to that of the philosopher Hans Albert who argued that the ceteris paribus conditions on which the marginalist theory of demand rested rendered the theory itself an empty tautology and completely closed to experimental testing.[14] In essence, demand and supply curve (theoretical line of quantity of a product which would have been offered or requested for given price) is purely ontological and could never been demonstrated empirically.

Another criticism comes from the assertion that neither cardinal nor ordinal utility is empirically observable in the real world. In the case of cardinal utility it is impossible to measure the level of satisfaction "quantitatively" when someone consumes or purchases an apple. In case of ordinal utility, it is impossible to determine what choices were made when someone purchases, for example, an orange. Any act would involve preference over a vast set of choices (such as apple, orange juice, other vegetable, vitamin C tablets, exercise, not purchasing, etc.).[15][16]

Other questions of what arguments ought to enter into a utility function are difficult to answer, yet seem necessary to understanding utility. Whether people gain utility from coherence of wants, beliefs or a sense of duty is key to understanding their behavior in the utility organon.[17] Likewise, choosing between alternatives is itself a process of determining what to consider as alternatives, a question of choice within uncertainty.[18]

An evolutionary psychology perspective is that utility may be better viewed as due to preferences that maximized evolutionary fitness in the ancestral environment but not necessarily in the current one.[19]

See also

References

  1. ^ Debreu, Gérard (1954), "Representation of a preference ordering by a numerical function", in Thrall, Robert M.; Coombs, Clyde H.; Raiffa, Howard (eds.), Decision processes, New York: Wiley, pp. 159–167, OCLC 639321.
  2. ^ Marshall, Alfred (1920). Principles of Economics. An introductory volume (8th ed.). London: Macmillan.
  3. ^ Von Neumann, J., Morgenstern, O. (1953). Theory of games and economic behavior, 3rd ed., Princeton University Press.
  4. ^ Kahneman, D., Tversky, A. (1979). Prospect theory: An analysis of decision under risk. Econometrica, 47, 263-291.
  5. ^ Grechuk, B., Zabarankin, M. (2016). Inverse portfolio problem with coherent risk measures Archived 3 September 2017 at the Wayback Machine, European Journal of Operational Research 249(2), 740-750.
  6. ^ Ingersoll, Jonathan E., Jr. (1987). Theory of Financial Decision Making. Totowa: Rowman and Littlefield. p. 21. ISBN 0-8476-7359-6.
  7. ^ Castagnoli, E. and M. LiCalzi. "Expected Utility Theory without Utility." Theory and Decision, 1996
  8. ^ Bordley, R. and M. LiCalzi. "Decision Analysis with Targets instead of Utilities," Decisions in Economics and Finance. 2000.
  9. ^ Bordley, R. And C.Kirkwood. Multiattribute preference analysis with Performance Targets. Operations Research. 2004.
  10. ^ Bordley, R.; Pollock, S. (2009). "A Decision-Analytic Approach to Reliability-Based Design Optimization". Operations Research. 57 (5): 1262–1270. doi:10.1287/opre.1080.0661.
  11. ^ Berger, J. O. (1985). "Utility and Loss". Statistical Decision Theory and Bayesian Analysis (2nd ed.). Berlin: Springer-Verlag. ISBN 3-540-96098-8.
  12. ^ Robinson, Joan (1962). Economic Philosophy. Harmondsworth, Middle-sex, UK: Penguin Books.
  13. ^ Pilkington, Philip (17 February 2014). "Joan Robinson's Critique of Marginal Utility Theory". Fixing the Economists. Archived from the original on 13 July 2015.
  14. ^ Pilkington, Philip (27 February 2014). "utility Hans Albert Expands Robinson's Critique of Marginal Utility Theory to the Law of Demand". Fixing the Economists. Archived from the original on 19 July 2015.
  15. ^ "Revealed Preference Theory". Archived from the original on 16 July 2011. Retrieved 11 December 2009.CS1 maint: BOT: original-url status unknown (link)
  16. ^ "Archived copy" (PDF). Archived from the original (PDF) on 15 October 2008. Retrieved 9 August 2008.CS1 maint: Archived copy as title (link)
  17. ^ Klein, Daniel (May 2014). "Professor" (PDF). Econ Journal Watch. 11 (2): 97–105. Archived (PDF) from the original on 5 October 2014. Retrieved 15 November 2014.
  18. ^ Burke, Kenneth (1932). Towards a Better Life. Berkeley, Calif.:: University of California Press.
  19. ^ Paul H. Rubin and C. Monica Capra. The evolutionary psychology of economics. In Roberts, S. C. (2011). Roberts, S. Craig (ed.). "Applied Evolutionary Psychology". Oxford University Press. doi:10.1093/acprof:oso/9780199586073.001.0001. ISBN 9780199586073.

Further reading

  • Anand, Paul (1993). Foundations of Rational Choice Under Risk. Oxford: Oxford University Press. ISBN 0-19-823303-5.
  • Fishburn, Peter C. (1970). Utility Theory for Decision Making. Huntington, NY: Robert E. Krieger. ISBN 0-88275-736-9.
  • Georgescu-Roegen, Nicholas (August 1936). "The Pure Theory of Consumer's Behavior". Quarterly Journal of Economics. 50 (4): 545–593. doi:10.2307/1891094. JSTOR 1891094.
  • Gilboa, Itzhak (2009). Theory of Decision under Uncertainty. Cambridge: Cambridge University Press. ISBN 978-0-521-74123-1.
  • Kreps, David M. (1988). Notes on the Theory of Choice. Boulder, CO: West-view Press. ISBN 0-8133-7553-3.
  • Nash, John F. (1950). "The Bargaining Problem". Econometrica. 18 (2): 155–162. doi:10.2307/1907266. JSTOR 1907266.
  • Neumann, John von & Morgenstern, Oskar (1944). Theory of Games and Economic Behavior. Princeton, NJ: Princeton University Press.
  • Nicholson, Walter (1978). Micro-economic Theory (Second ed.). Hinsdale: Dryden Press. pp. 53–87. ISBN 0-03-020831-9.
  • Plous, S. (1993). The Psychology of Judgement and Decision Making. New York: McGraw-Hill. ISBN 0-07-050477-6.

External links

Compact sport utility vehicle

Compact sport utility vehicle, also known as compact SUV, is a class of small sport utility vehicles that is larger than Mini SUVs, but smaller than mid-size SUVs.

The 1982 Chevrolet S-10 Blazer and 1984 Ford Bronco II were considered compact-sized compared with the Chevrolet K5 Blazer, and Ford Bronco full-size 4x4s which they were sold alongside. However, a more direct link to the modern compact SUV is found in the 1988 Suzuki Vitara. Another early compact SUV was the 1997 Isuzu VehiCROSS.

In markets such as India, they were originally a sub-segment of Utility Vehicles, but the smaller size versions have grown to become a dominant segment.

Crossover (automobile)

A crossover SUV— also called crossover or CUV— is a type of sports utility vehicle (SUV) that uses a unibody construction. Crossovers are often based on a platform shared with a passenger car; as a result they typically have better comfort and fuel economy, but less off-road capability (many crossovers are sold without all-wheel drive) than truck-based SUVs.There are various inconsistencies about whether vehicles are considered crossovers or SUVs; therefore the term SUV is often used as a catch-all for both crossovers and SUVs.

Early crossovers include the 1979 AMC Eagle and 1994 Toyota RAV4.

In the United States as of 2006 more than 50% of the overall SUV market were crossover models. Crossovers have also become increasingly popular in Europe since the early 2010s.

District

A district is a type of administrative division that, in some countries, is managed by local government. Across the world, areas known as "districts" vary greatly in size, spanning regions or counties, several municipalities, subdivisions of municipalities, school district, or political district.

Ford Explorer

The Ford Explorer is a range of SUVs manufactured by Ford Motor Company. Introduced in 1990 for the 1991 model year, the Explorer was the first four-door SUV produced by Ford, replacing the two-door Bronco II. Six generations of the Explorer have been produced.The sixth generation was unveiled in January 2019. As with the Ranger, the Explorer derives its name from a trim package used on the F-Series, used from 1967 to 1986. Originally slotted below the full-size Bronco in the Ford truck line, the current Explorer is slotted between the Escape/Kuga, Edge and standard-wheelbase Expedition.

For its first two generations, the Explorer was produced in both two-door (as the Explorer Sport) and four-door configurations. Upon the introduction of the third generation, the Explorer was produced exclusively as a four-door SUV; the Explorer Sport was discontinued in 2003. The Sport name was resurrected in 2012, but as a performance version of the standard four-door Explorer. The Explorer has been offered with a number of powertrain layouts during its production. The first four generations offered rear-wheel drive as standard, with part-time four-wheel drive and all-wheel drive options; the fifth generation offered front-wheel drive and all-wheel drive, while the sixth generation reverted to rear-wheel drive with optional all-wheel drive.

During its production, numerous variants of the Explorer have been marketed, with Lincoln-Mercury selling the four-door Explorer as the Mercury Mountaineer (1996–2010) and the Lincoln Aviator (2002–2005; 2019–); Mazda sold the Explorer Sport as the Mazda Navajo (1990–1994). The Explorer Sport Trac is a mid-size pickup truck derived from the four-door Explorer; two generations were produced from 1999 to 2010. For police use, Ford developed the Ford Police Interceptor Utility from the fifth-generation Explorer (replacing the Ford Crown Victoria Police Interceptor); a specially modified Special Service Vehicle version is also available from Ford Fleet for law enforcement agencies, fire departments, and EMS agencies.

Jeep Wrangler

The Jeep Wrangler is a series of compact and mid-size (Wrangler Unlimited and Wrangler 2-door JL) four-wheel drive off-road SUVs, manufactured by Jeep since 1986, and currently in its fourth generation. The Wrangler JL, the most recent generation, was unveiled in late 2017 and is produced at Jeep's Toledo Complex.

The Wrangler is arguably an indirect progression from the World War II Jeep, through the CJ (Civilian Jeeps) produced by Willys, Kaiser-Jeep and American Motors Corporation (AMC) from the mid-1940s through 1980s. Although neither AMC nor Chrysler (after its purchase of AMC in 1987) have claimed that the Wrangler was a direct descendant of the original military model — both the CJ Jeeps and the conceptually consistent Wrangler, with their solid axles and open top, have been called the Jeep model as central to Jeep's brand identity as the rear-engined 911 is to Porsche.Similar to the Willys MB and the CJ Jeeps before it, all Wrangler models continue to use a separate body and frame, rigid live axles both front and rear, a tapering nose design with flared fenders, a fold-flat windshield, and can be driven without doors. Also, with few exceptions, they have part-time four-wheel drive systems, with the choice of high and low gearing, and standard are open bodies with removable hard- or soft-tops. However, the Wrangler series was specifically redesigned to be safer and more comfortable on-road, to attract more daily drivers, by upgrading its suspension, drivetrain, and interior, compared to the CJ line. The suspension on all Wranglers included trackbars and anti-roll bars, and, from the 1997 TJ onwards, front and rear coil springs instead of the previous leaf-springs.From 2004 the Wrangler has been complemented with long-wheelbase versions, called Wrangler Unlimited (until the release of the JL generation). 2004-2006 models were longer versions with 2 doors. In 2004 only automatic transmission equipped “Unlimited” versions were sold. In 2005 both an automatic and manual 6-speed (NSG-370) were offered. Since 2007, the long-wheelbase Wranglers were four-door models, offering over 20 in (508 mm) more room. By mid 2017 the four-door models represented three quarters of all new Wranglers on the market.

List of dog breeds

Dogs have been selectively bred for thousands of years, sometimes by inbreeding dogs from the same ancestral lines, while at other times by mixing dogs from very different lines. The process continues today, resulting in a widening in appearance without speciation, "from the Chihuahua to the Great Dane".The following list uses a wide interpretation of the word "breed". Breeds are usually categorized by the functional type from which the breed was developed. The basic types are companion dogs, guard dogs, hunting dogs, herding dogs and working dogs, although there are many other types and subtypes. Breeds listed here may be traditional breeds with long histories as registered breeds, rare breeds with their own registries, or new breeds that may still be under development.

In some cases, a breed's origin overlaps the boundaries of two or more countries; the dog is normally listed only in the country with which it is most commonly associated; for example, by its designated country according to the Fédération Cynologique Internationale (FCI). Some dogs, such as the Löwchen, have an uncertain origin and are thus listed under several countries.

List of macOS components

This is a list of macOS (earlier called Mac OS X) components, features that are included in the current Mac operating system.

Marginal utility

In economics, utility is the satisfaction or benefit derived by consuming a product; thus the marginal utility of a good or service is the change in the utility from an increase in the consumption of that good or service.

In the context of cardinal utility, economists sometimes speak of a law of diminishing marginal utility, meaning that the first unit of consumption of a good or service yields more utility than the second and subsequent units, with a continuing reduction for greater amounts. Therefore, the fall in marginal utility as consumption increases is known as diminishing marginal utility. Mathematically:

MU1>MU2>MU3......>MUn

Minivan

Minivan is an American car classification for vehicles which are designed to transport passengers in the rear seating row(s), have reconfigurable seats in two or three rows. The equivalent terms in British English are Multi-purpose Vehicle (MPV), people carrier and people mover. Minivans often have a 'one-box' or 'two-box' body configuration, a high roof, a flat floor, a sliding door for rear passengers and high H-point seating.

Compared with a full-size van, a minivan is based on a passenger car platform and has a less tall body (in order to fit inside a typical garage door opening).

The largest size of minivans is also referred to as 'Large MPV' and became popular following the introduction of the 1984 Renault Espace and Dodge Caravan. Typically, these have platforms derived from D-segment passenger cars or compact pickups. Since the 1990s, the smaller Compact MPV and Mini MPV sizes of minivans have also become popular. If the term 'minivan' is used without specifying a size, it usually refers to the largest size (i.e. Large MPV).

Pickup truck

A pickup truck is a light-duty truck having an enclosed cab and an open cargo area with low sides and tailgate. Once a work tool with few creature comforts, in the 1950s consumers began purchasing pickups for lifestyle reasons, and by the 1990s, less than 15% of owners reported use in work as the pickup truck's primary purpose. Today in North America, the pickup is mostly used as a passenger car and accounts for about 18% of total vehicles sold in the United States.Full-sized pickups and SUVs are an important source of revenue for GM, Ford, and FCA's Ram, accounting for more than two-thirds of their global pretax earnings, though the vehicles make up just 16% of North American vehicle production. The vehicles have a high profit margin and a high price, with 40% of Ford F-150s selling for US$40,000 or more.The term pickup is of unknown origin. It was used by Studebaker in 1913 and by the 1930s, "pick-up" (hyphenated) had become the standard term. In Australia and New Zealand, "ute", short for utility vehicle, is used for both pickups and coupé utilities. In South Africa, people of all language groups use the term bakkie, a diminutive of bak, Afrikaans for bowl/container, due to the cargo area's similarities with a bowl.

Public utility

A public utility (usually just utility) is an organization that maintains the infrastructure for a public service (often also providing a service using that infrastructure). Public utilities are subject to forms of public control and regulation ranging from local community-based groups to statewide government monopolies.

The term utilities can also refer to the set of services provided by these organizations consumed by the public: Coal, electricity, natural gas, water, sewage, telephone, and transportation. Broadband internet services (both fixed-line and mobile) are increasingly being included within the definition.

Risk aversion

In economics and finance, risk aversion is the behavior of humans (especially consumers and investors), who, when exposed to uncertainty, attempt to lower that uncertainty. It is the hesitation of a person to agree to a situation with an unknown payoff rather than another situation with a more predictable payoff but possibly lower expected payoff. For example, a risk-averse investor might choose to put their money into a bank account with a low but guaranteed interest rate, rather than into a stock that may have high expected returns, but also involves a chance of losing value.

Rugby league positions

A rugby league team consists of thirteen players on the field, with four substitutes on the bench. Each of the thirteen players is assigned a position, normally with a standardised number, which reflects their role in attack and defence, although players can take up any position at any time.

Players are divided into two general types, forwards and backs. Forwards are generally chosen for their size and strength. They are expected to run with the ball, to attack, and to make tackles. Forwards are required to improve the team's field position thus creating space and time for the backs. Backs are usually smaller and faster, though a big, fast player can be of advantage in the backs. Their roles require speed and ball-playing skills, rather than just strength, to take advantage of the field position gained by the forwards. Typically forwards tend to operate in the centre of the field, while backs operate nearer to the touch-lines, where more space can usually be found.

Sikorsky UH-60 Black Hawk

The Sikorsky UH-60 Black Hawk is a four-bladed, twin-engine, medium-lift utility helicopter manufactured by Sikorsky Aircraft. Sikorsky submitted the S-70 design for the United States Army's Utility Tactical Transport Aircraft System (UTTAS) competition in 1972. The Army designated the prototype as the YUH-60A and selected the Black Hawk as the winner of the program in 1976, after a fly-off competition with the Boeing Vertol YUH-61.

Named after the Native American war leader Black Hawk, the UH-60A entered service with the U.S. Army in 1979, to replace the Bell UH-1 Iroquois as the Army's tactical transport helicopter. This was followed by the fielding of electronic warfare and special operations variants of the Black Hawk. Improved UH-60L and UH-60M utility variants have also been developed. Modified versions have also been developed for the U.S. Navy, Air Force, and Coast Guard. In addition to U.S. Army use, the UH-60 family has been exported to several nations. Black Hawks have served in combat during conflicts in Grenada, Panama, Iraq, Somalia, the Balkans, Afghanistan, and other areas in the Middle East.

Sport utility vehicle

Sport utility vehicle (SUV) is a category of motor vehicles which combine elements of road-going passenger cars with features from off-road vehicles, such as raised ground clearance and four-wheel drive.

There is no commonly agreed definition of an SUV, and usage varies between countries. Some definitions claim that an SUV must be built on a light truck chassis, however broader consider that any vehicle with off-road design features is an SUV. Crossover SUV is defined as an SUV built with a unibody construction (as per passenger cars), however in many cases crossovers are simply referred to as SUVs. In some countries— such as the United States— SUVs have been classified as "light trucks", resulting in more lenient regulations compared to passenger cars.

The predecessors to SUVs date back to military and low-volume models from the late 1930s, and the four-wheel drive station wagons / carryalls that began to be introduced in 1949. The 1984 Jeep Cherokee (XJ) is considered to be the first SUV in the modern style. Most SUVs produced today use unibody contruction (as per passenger cars), however in the past many SUVs used body-on-frame construction.

During the late 1990s and early 2000s, the populary of SUVs greatly increased, often at the expense of the popularity of large sedans and station wagons. More recently, smaller SUVs and crossovers have become increasingly popular. SUVs are currently the world's largest automotive segment and accounted for 36.8% of the world's passenger car market in 2017.

Utilitarianism

Utilitarianism is a family of consequentialist ethical theories that promotes actions that maximize happiness and well-being for the majority of a population. Although different varieties of utilitarianism admit different characterizations, the basic idea behind all of them is to in some sense maximize utility, which is often defined in terms of well-being or related concepts. For instance, Jeremy Bentham, the founder of utilitarianism, described utility as

that property in any object, whereby it tends to produce benefit, advantage, pleasure, good, or happiness...[or] to prevent the happening of mischief, pain, evil, or unhappiness to the party whose interest is considered.Utilitarianism is a version of consequentialism, which states that the consequences of any action are the only standard of right and wrong. Unlike other forms of consequentialism, such as egoism and altruism, utilitarianism considers the interests of all beings equally.

Proponents of utilitarianism have disagreed on a number of points, such as whether actions should be chosen based on their likely results (act utilitarianism) or whether agents should conform to rules that maximize utility (rule utilitarianism). There is also disagreement as to whether total (total utilitarianism), average (average utilitarianism) or minimum utility should be maximized.

Though the seeds of the theory can be found in the hedonists Aristippus and Epicurus, who viewed happiness as the only good, the tradition of utilitarianism properly began with Bentham, and has included John Stuart Mill, Henry Sidgwick, R. M. Hare, David Braybrooke, and Peter Singer. It has been applied to social welfare economics, the crisis of global poverty, the ethics of raising animals for food and the importance of avoiding existential risks to humanity.

Utility player

In sports, a utility player is one who can play several positions competently. Sports in which the term is often used include football, baseball, rugby union, rugby league, water polo, and softball.

The term has gained prominence in all sports due to its use in fantasy leagues, but in rugby and rugby league, it is commonly used by commentators to recognize a player's versatility.

Utility pole

A utility pole is a column or post used to support overhead power lines and various other public utilities, such as electrical cable, fiber optic cable, and related equipment such as transformers and street lights. It can be referred to as a transmission pole, telephone pole, telecommunication pole, power pole, hydro pole, telegraph pole, or telegraph post, depending on its application. A stobie pole is a multi-purpose pole made of two steel joists held apart by a slab of concrete in the middle, generally found in South Australia.

Electrical wires and cables are routed overhead on utility poles as an inexpensive way to keep them insulated from the ground and out of the way of people and vehicles. Utility poles can be made of wood, metal, concrete, or composites like fiberglass. They are used for two different types of power lines; subtransmission lines which carry higher voltage power between substations, and distribution lines which distribute lower voltage power to customers.

The first poles were used in 1843 by telegraph pioneer William Fothergill Cooke who used them on a line along the Great Western Railway. Utility poles were first used in the mid-19th century in America with telegraph systems, starting with Samuel Morse who attempted to bury a line between Baltimore and Washington, D.C., but moved it above ground when this system proved faulty. Today, underground distribution lines are increasingly used as an alternative to utility poles in residential neighborhoods, due to poles' perceived ugliness.

Utility software

Utility software is system software designed to help to analyze, configure, optimize or maintain a computer. It is used to support the computer infrastructure - in contrast to application software, which is aimed at directly performing tasks that benefit ordinary users.However, utilities often form part of application systems . For example a batch job may run user-written code to update a database and may then include a step that runs a utility to back up the database, or a job may run a utility to compress a disk before copying files.

Although a basic set of utility programs is usually distributed with an operating system (OS), and utility software is considered part of the operating system, users often install replacements or additional utilities. Those utilities may provide additional facilities to carry out tasks that are beyond the capabilities of the operating system.

Many utilities that might affect the entire computer system require the user to have elevated privileges, while others that operate only on the user's data do not.

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