Here, the twin assumptions of rationality and market efficiency lead to modern portfolio theory ( the CAPM ), and to the Black – Scholes theory for option valuation ; it further studies phenomena and models where these assumptions do not hold, or are extended.

Researchers performing twin studies have argued that differences between people on behavioral traits such as creativity, extroversion and aggressiveness are between 45 % to 75 % due to genetic differences, and intelligence is said by some to be about 80 % genetic after one matures ( discussed at Intelligence quotient # Shared_family_environment ).

However, twin and adoption studies suggest that genetic factors interact with environmental factors for stuttering to occur, and many stutterers have no family history of the disorder.

Amidst the vogue enjoyed by existentialism and positivism in early 20th century Europe, Adorno advanced a dialectical conception of natural history that critiqued the twin temptations of ontology and empiricism through studies of Kierkegaard and Husserl.

Important evidence against the tabula rasa model of the mind comes from Behavioural genetics, especially twin and adoption studies.

He cites the Burt Affair, about the allegedly fraudulent, oft-cited twin studies, by Cyril Burt ( 1883 – 1971 ), wherein he claimed that human intelligence is highly heritabile.

To disentangle the effects of genes and environment, behavioral geneticists perform adoption and twin studies.

Much of the medical literature in this area is composed of case studies of single or twin pregnancies, and although some have reported serious complications, the majority have found ECT to be safe.

Family-linkage and twin studies have indicated that genetic factors often play an important role in the development of mental disorders.

A number of twin studies have attempted to compare the relative importance of genetics and environment in the causation of sexual orientation.

A meta-study by Hershberger ( 2001 ) compares the results of eight different twin studies: among those, all but two showed MZ twins having much higher concordance of sexual orientation than DZ twins, suggesting a non-negligible genetic component.

In terms of variation between individual people, more than 100 twin and adoption studies studies have been conducted in recent decades examining the genetic basis of aggressive behavior and related constructs such as conduct disorders.

Eliot Cohen, the director of strategic studies at the Paul H. Nitze School of Advanced International Studies at Johns Hopkins University, declared in The Wall Street Journal, a little more than a month after the attacks on the twin towers and the Pentagon, that the struggle against terrorism was more than a law-enforcement operation, and would require military conflict beyond the invasion of Afghanistan.

This genetic influence on decision-making behaviors has been found through classical twin studies, in which decision-making tendencies are self-reported by pairs of twins and then compared between monozygotic and dizygotic twins.

Heritability is an important concept in quantitative genetics, particularly in selective breeding and behaviour genetics ( for instance twin studies ), but is less widely used in population genetics.

Modern twin studies have shown that almost all traits are in part influenced by genetic differences, with some characteristics showing a strong influence ( e. g. height ), others an intermediate level ( e. g. intelligence quotient ) and some more complex heritabilities, with evidence for different genes affecting different aspects of the trait-as in the case of autism.

Fatefully, however, Thorndike incorrectly reasoned that his data gave support for there being one, not two types of twins: Missing the critical distinction that makes within-family twin studies such a powerful resource in psychology and medicine.

While concordance studies compare traits which are either present or absent in each twin, correlational studies compare the agreement in continuously varying traits across twins.

Not really identical: epigenetic differences in monozygotic twins and implications for twin studies in psychiatry.

Twin concordance studies have demonstrated that when one monozygotic twin has alopecia areata, there is more than a 50 % chance that the other twin will be affected, whereas there is zero concordance in dizygotic twin pairs.

It is his research in behavior genetics, most notably in studying the heritability of intelligence ( as measured in IQ tests ) using twin studies that have created the most controversy, frequently referred to as " the Burt Affair.

* Identical twin concordance rate of 10 % and dizygotic twin concordance rate of 3 %

For a group of twins in which at least one member of each pair is affected, probandwise concordance is a measure of the proportion of twins who have the illness who have an affected twin and can be calculated with the formula of 2C /( 2C + D ), in which C is the number of concordant pairs and D is the number of discordant pairs.

These hypotheses would explain the result of adoption and twin studies that have been carried out, indicating that twins separated at birth have a higher likelihood of concordance for addictive disease than would be expected were there not a genetic component, and indicating that these twins have a lower likelihood of concordance for addictive disease than do twins who remain together in identical environments.

In the early 1990s Bailey and Richard Pillard coauthored a series of twin studies which examined the rate of concordance of sexual identity among monozygotic twins ( 52 % concordance ), dizygotic twins of the same sex ( 22 %), non-twin siblings of the same sex, and adoptive siblings of the same sex ( 11 %).

This means that if one twin has PMS, then the other twin is more likely than average to have PMS, and it suggests that the cause is partly genetic.

Finally, whatever the techniques used, a twin goal is common to all preventive casework service: to cushion or reduce the force of the stress impact while at the same time to encourage and support family members to mobilize and use their ego capacities.

Apollo is the son of Zeus and Leto, and has a twin sister, the chaste huntress Artemis.

It is flanked by twin towers decorated with blind arcading.

While this does bear some similarity with the classic posture of cowboys firing their twin revolvers from the hip, in games this posture is almost never reflected, with almost all game characters firing twin guns at shoulder level, straight-armed.

The game, starring the twin Bubble Dragons and, is an action-platform game in which players travel through one hundred different stages, blowing and bursting bubbles, avoiding enemies and collecting a variety of items.

Deception Pass is a dramatic seascape where the tidal flow and whirlpools beneath the twin bridges connecting Fidalgo Island to Whidbey Island move quickly.

A possible defeater or overriding proposition for such a claim could be a true proposition like, " Tom Grabit's identical twin Sam is currently in the same town as Tom.

The twin goals of research are to determine whether the treatment actually works ( called efficacy ) and whether it is sufficiently safe.

In performance, a solo fiddler, or one fiddler or two with a group of other instrumentalists, is the norm, though twin fiddling is represented in some North American, Scandinavian, Scottish and Irish styles.

* The Scaled Composites Model 367 BiPod is a developmental hybrid using joined fuselages, and twin combustion engines powering four 15 kW electric propellers.

" One of the twin brothers returns home from shooting in the Corsican mountains, and is visited by the ghost of the other twin.

Among the many race victories of his early desmo twin, the 1978 legendary return of Mike Hailwood at the Isle of Man is perhaps the most memorable.

Being the historic core of Europe and the " twin engine for European integration ", the cooperation with France is one of the most central elements of German foreign policy.

Her twin brother Helios is the sun god.

A goddess, probably Hekate or else Artemis, is depicted with a bow, dog and twin torches.

Article II of the IAEA Statute defines the Agency's twin objectives as promoting peaceful uses of atomic energy and "< nowiki > ensur </ nowiki >, so far as it is able, that assistance provided by it or at its request or under its supervision or control is not used in such a way as to further any military purpose.

* 2011 – Norway is the victim of twin terror attacks, the first being a bomb blast which targeted government buildings in central Oslo, the second being a massacre at a youth camp on the island of Utøya.

In the Hebrew Bible, he is the son of Isaac and Rebekah, the grandson of Abraham, Sarah and of Bethuel, and the younger twin brother of Esau.

This Kouros is the larger twin of the one now kept in the Metropolitan Museum of Art in New York, and both were made by the same anonymous sculptor called the " Dipylon Master ".

In the film K-PAX, the constellation of Lyra is the location of the planet K-PAX, an inhabited world that orbits twin stars and has seven moons.

The name " Puppeteer " is purportedly derived from the twin " heads " ( not enclosing brains ) which perform as both mouths and hands, which strongly resemble sock puppets.