Trade-off

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 suggests 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
and earning $150,000 as a doctor after 7 years of study. 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 but earning $150,000 or more per year
after 7 years of study.

Contents
Examples
In economics
In other specific fields
See also
Further reading
References

Examples
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. The meaning of trade off quite similar to that of Opportunity cost

In economics
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 fields

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.

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.[10]

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,[11] called the
Architecture Tradeoff Analysis Method (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 also
Architecture tradeoff analysis method
Bias–variance tradeoff
Biological constraints
Carrier's constraint
Detection error tradeoff
Evolutionary medicine
Evolutionary physiology
Negotiation
Paradox
Pareto front
Patient trade-off
Space–time tradeoff