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A trade-off (or tradeoff) is a situational decision that involves diminishing or losing one quality, quantity or property of a set or design in return for gains in other aspects. In simple terms, a tradeoff is where one thing increases and another must decrease. Tradeoffs stem from limitations of many origins, including simple physics - for instance, only a certain volume of objects can fit into a given space, so a full container must remove some items in order to accept any more, and vessels can carry a few large items or multiple small items. Tradeoffs also commonly refer to different configurations of a single item, such as the tuning of strings on a guitar to enable different notes to be played, as well as allocation of time and attention towards different tasks.

The concept of a tradeoff implies a tactical or strategic choice made with full comprehension of the advantages and disadvantages of each setup. An economic example is the decision to invest in stocks, which are risky but carry great potential return, versus bonds, which are generally safer but with lower potential returns.

The term is also used widely in an evolutionary context, in which case the processes of natural selection and sexual selection are in reference as the ultimate decisive factors.[1] In biology, the concepts of tradeoffs and constraints are often closely related.[2] In economics, a trade-off is commonly expressed in terms of the opportunity cost of one potential choice, which is the loss of the best available alternative.[3]

An opportunity cost example of trade-offs for an individual would be the decision by a full-time worker to take time off work with a salary of $50,000 to attend medical school, with annual tuition of $30,000. If we assume for the sake of simplicity that the medical school only allows full-time study, then the individual considering stopping work would face a trade-off between not going to medical school and earning $50,000 at work, or going to medical school and losing $50,000 in salary and having to pay $30,000 in tuition.

Contents

ExamplesEdit

The concept of a trade-off is often used to describe situations in everyday life.[4][5] The old saying "do not put all of your eggs into one basket" implies a trade-off with respect to spreading risk, as when one buys a mutual fund composed of many stocks rather than only one or a few stocks that may have a higher expected value of return.

Similarly, trash cans that are used inside and then taken out to the street and emptied into a Dumpster can be small or large. A large trash can does not need to be taken out to the Dumpster so often, but it may become so heavy when full that the user risks strain or back injury when moving it. The choice of waste receptacle is a trade-off between the frequency of needing to take the trash out for the Dumpster versus the ease and safety of use. In the case of food waste, a second trade-off presents itself as large trash cans are more likely to sit for a long time in the kitchen, leading to higher levels of decomposing food indoors and a potential pest attraction. With a small trash can, the can will be taken out to the Dumpster more often, thus eliminating the persist rot that attracts pests. Of course, a user of a large trashcan could carry the can outside frequently anyway, but the heavier can would weigh more and the user would have to think more about when to take the can out, or confine themselves to a schedule, compared to a smaller can which is evidently full when it takes taking out.

In cold climates, mittens in which all the fingers are in the same compartment serve well to keep the hands warm, but this arrangement also confines finger movement and prevents the full range of hand function; gloves, with their separate fingers, do not have this drawback, but they do not keep the fingers as warm as mittens do. As such, with mittens and gloves, warmth versus dexterity is the trade-off. In a like fashion, warm coats are often bulky and hence they impede freedom of movement for the wearer. Thin coats, such as those worn by winter sports athletes, give the wearer more freedom of movement, but they are not as warm.

When copying music from compact discs to a computer, lossy compression formats, such as MP3, are used routinely to save hard disk space, but information is "thrown away" to the detriment of sound quality. Lossless compression schemes, such as FLAC or ALAC take much more disc space, but do not affect the sound quality as much, thus providing better sound.

Large cars can carry many people (five or more), and since they have larger crumple zones, they may be safer in an accident. However they also tend to be heavy (and often not very aerodynamic) and hence have relatively poor fuel economy. Small cars like the Smart Car can only carry two people, and their light weight means they are very fuel efficient. At the same time, the smaller size and weight of small cars means that they have smaller crumple zones, which means occupants are less protected in case of an accident. In addition, if a small car has an accident with a larger, heavier car, the occupants of the smaller car will fare more poorly. Thus car size (large versus small) involves multiple tradeoffs regarding passenger capacity, accident safety and fuel economy.

In athletics, sprint running demands different physical attributes from running a marathon. As such, the two contests have distinct events in competitions such as the Olympics, and each pursuit features distinct teams of athletes. Whether a professional runner is better suited to marathon running versus sprinting is a trade-off based on the runner's morphology and physiology (e.g., variation in muscle fiber type), as well as the runner's individual interest, preference and other motivational factors. This tradeoff is chiefly from the perspective of a sport's recruiter, who decides what role a prospective athlete would best suit on a team.

In economicsEdit

In economics a trade-off is expressed in terms of the opportunity cost of a particular choice, which is the loss of the most preferred alternative given up. A tradeoff, then, involves a sacrifice that must be made to obtain a certain product, service or experience, rather than others that could be made or obtained using the same required resources. For example, for a person going to a basketball game, their opportunity cost is the loss of the alternative of watching a particular television program at home. If the basketball game occurs during her or his working hours, then the opportunity cost would be several hours of lost work, as she/he would need to take time off work.

Many factors affect the tradeoff environment within a particular country, including availability of raw materials, a skilled labor force, machinery for producing a product, technology and capital, market rate to produce that product on reasonable time scale, and so forth.

A trade-off in economics is often illustrated graphically by a Pareto frontier (named after the economist Vilfredo Pareto), which shows the greatest (or least) amount of one thing that can be attained for each of various given amounts of the other. As an example, in production theory the trade-off between output of one good and output of another is illustrated graphically by the production possibilities frontier. The Pareto frontier is also used in multi-objective optimization. In finance, the capital asset pricing model includes an efficient frontier that shows the highest level of expected return that any portfolio could have given any particular level of risk, as measured by the variance of portfolio return.

In other specific fieldsEdit

In biology and microbiology, tradeoffs occur when a beneficial change in one trait is linked to a detrimental change in another trait.[6]

Tradeoffs are important in engineering. For example, in electrical engineering, negative feedback is used in amplifiers to trade gain for other desirable properties, such as improved bandwidth, stability of the gain and/or bias point, noise immunity, and reduction of nonlinear distortion. Similarly, tradeoffs are used to maximise power efficiency in medical devices whilst guaranteeing the required measurement quality[7].

In demography, tradeoff examples may include maturity, fecundity, parental care, parity, senescence, and mate choice. For example, the higher the fecundity (number of offspring), the lower the parental care that each offspring will receive. Parental care as a function of fecundity would show a negative sloped linear graph. A related phenomenon, known as demographic compensation, arises when the different components of species life cycles (survival, growth, fecundity, etc) show negative correlations across the distribution ranges[8][9]. For example, survival may be higher towards the northern edge of the distribution, while fecundity or growth increases towards the south, leading to a compensation that allows the species to persist along an environmental gradient. Contrasting trends in life cycle components may arise through tradeoffs in resource allocation, but also through independent but opposite responses to environmental conditions.

In computer science, tradeoffs are viewed as a tool of the trade. A program can often run faster if it uses more memory (a space–time tradeoff). Consider the following examples:

  • By compressing an image, you can reduce transmission time/costs at the expense of CPU time to perform the compression and decompression. Depending on the compression method, this may also involve the tradeoff of a loss in image quality.
  • By using a lookup table, you may be able to reduce CPU time at the expense of space to hold the table, e.g. to determine the parity of a byte you can either look at each bit individually (using shifts and masks), or use a 256-entry table giving the parity for each possible bit-pattern, or combine the upper and lower nibbles and use a 16-entry table.
  • For some situations (e.g. string manipulation), a compiler may be able to use inline code for greater speed, or call run-time routines for reduced memory; the user of the compiler should be able to indicate whether speed or space is more important.

The Software Engineering Institute has a specific method for analysing tradeoffs,[10] called the Architectural Tradeoff Analysis Method or ATAM.

Strategy board games often involve tradeoffs: for example, in chess you might trade a pawn for an improved position. In a worst-case scenario, a chess player might even tradeoff the loss of a valuable piece (even the Queen) to protect the King. In Go, you might trade thickness for influence.

Ethics often involves competing interests that must be traded off against each other, such as the interests of different people, or different principles (e.g. is it ethical to use information resulting from inhumane or illegal experiments to treat disease today?)

In medicine, patients and physicians are often faced with difficult decisions involving tradeoffs. One example is localized prostate cancer where patients need to weigh the possibility of a prolonged life expectancy against possible stressful or unpleasant treatment side-effects (patient trade-off).

Governmental tradeoffs are among the most controversial political and social difficulties of any time. All of politics can be viewed as a series of tradeoffs based upon which core values are most core to the most people or politicians. Political campaigns also involve tradeoffs, as when attack ads may energize the political base but alienate undecided voters.

With work schedules, employees will often use a tradeoff of "9/80" where an 80-hour work period is compressed into a narrow group of 9 nearly-9 hour working days over the traditional 10 8-hour working days, allowing the employee to take every second Friday off.

See alsoEdit

Further readingEdit

  • Albuquerque, R. L. de, K. E. Bonine, and T. Garland, Jr. 2015. Speed and endurance do not trade off in phrynosomatid lizards. Physiological and Biochemical Zoology 88:634–647.
  • Alexander, R. McN. 1985. The ideal and the feasible: physical constraints on evolution. Biol. J. Linn. Soc. 26:345-358.
  • Bennett, A. F., Lenski, R. E. 2007. An experimental test of evolutionary trade-offs during temperature adaptation. Proc. Natl. Acad. Sci. USA 104:8649-8654.
  • Campbell, D. E., and J. S. Kelly. 1994. Trade-off theory. The American Economic Review 84:422-426.
  • Haak, D. C., McGinnis, L. A., Levey, D. J., Tewksbury, J. J. 2012. Why are not all chilies hot? A trade-off limits pungency. Proc. R. Soc. B Biol. Sci. 279:2012-2017.
  • Roff, D. A., Fairbairn, D. J. 2007. The evolution of tradeoffs: where are we? J. Evol. Biol. 20:433-447.
  • Stearns, S. C. 1989. Trade-offs in life-history evolution. Functional Ecology 3:259-268.
  • Philipson, C. D. et al. 2014. A trait-based trade-off between growth and mortality: evidence from 15 tropical tree species using size-specific relative growth rates. Ecology & Evolution 4: 3675–3688. 10.1002/ece3.1186 10.1002/ece3.1186

ReferencesEdit

  1. ^ Garland, T., Jr. 2014. Quick guide: Tradeoffs. Current Biology 24:R60-R61.
  2. ^ "105_2013_12_05_Trade-offs_1". 
  3. ^ "Trade-Offs in Economics: Definition & Examples - Video & Lesson Transcript - Study.com". 
  4. ^ "Life Is a Series of Trade-offs". 
  5. ^ "All of Life is Trade-Offs". 
  6. ^ Keen, E. C. (2014). "Tradeoffs in bacteriophage life histories". Bacteriophage. 4 (1): e28365. doi:10.4161/bact.28365. PMC 3942329 . PMID 24616839. 
  7. ^ E. Aguilar Pelaez et al., "LED power reduction trade-offs for ambulatory pulse oximetry," 2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, Lyon, 2007, pp. 2296-2299. doi: 10.1109/IEMBS.2007.4352784, URL: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4352784&isnumber=4352185
  8. ^ Doak, Daniel F.; Morris, William F. "Demographic compensation and tipping points in climate-induced range shifts". Nature. 467 (7318): 959–962. doi:10.1038/nature09439. 
  9. ^ Villellas, Jesús; Doak, Daniel F.; García, María B.; Morris, William F. (2015-11-01). "Demographic compensation among populations: what is it, how does it arise and what are its implications?". Ecology Letters. 18 (11): 1139–1152. doi:10.1111/ele.12505. ISSN 1461-0248. 
  10. ^ http://www.sei.cmu.edu/architecture/tools/atam/