Carrot or Stick? Group Selection and the Evolution of Reciprocal Preferences

This paper studies the evolution of both characteristics of reciprocity - the willingness to reward friendly behavior and the willingness to punish hostile behavior. Firstly, preferences for rewarding as well as preferences for punishing can survive evolution provided individuals interact within separated groups. This holds even with randomly formed groups and even when individual preferences are unobservable. Secondly, preferences for rewarding survive only in coexistence with self-interested preferences. But preferences for punishing tend either to vanish or to dominate the population entirely. Finally, the evolution of preferences for rewarding and the evolution of preferences for punishing influence each other decisively. The existence of rewarders enhances the evolutionary success of punishers, but punishers crowd out rewarders

Structural positions and risk budgeting : quantifying the impact of structural positions and deriving implications for active portfolio management

Structural positions are very common in investment practice. A structural position is defined as a permanent overweighting of a riskier asset class relative to a prespecified benchmark portfolio. The most prominent example for a structural position is the equity bias in a balanced fund that arises by consistently overweighting equities in tactical asset allocation. Another example is the permanent allocation of credit in a fixed income portfolio with a government benchmark. The analysis provided in this article shows that whenever possible, structural positions should be avoided. Graphical illustrations based on Pythagorean theorem are used to make a connection between the active risk/return and the total risk/return framework. Structural positions alter the risk profile of the portfolio substantially, and the appeal of active management – to provide active returns uncorrelated to benchmark returns and hence to shift the efficient frontier outwards – gets lost. The article demonstrates that the commonly used alpha – tracking error criterion is not sufficient for active management. In addition, structural positions complicate measuring managers’ skill. The paper also develops normative implications for active portfolio management. Tactical asset allocation should be based on the comparison of expected excess returns of an asset class to the equilibrium risk premium of the same asset class and not to expected excess returns of other asset classes. For the cases, where structural positions cannot be avoided, a risk budgeting approach is introduced and applied to determine the optimal position size. Finally, investors are advised not to base performance evaluation only on simple manager rankings because this encourages managers to take structural positions and does not reward efforts to produce alpha. The same holds true for comparing managers’ information ratios. Information ratios, in investment practice defined as the ratio of active return to active risk, do not uncover structural positions

The Obama/Pentagon War Narrative, the Real War and Where Afghan Civilian Deaths Do Matter

This article investigates two related issues: (1) the on-the-ground experience of the fierce US war. in Afghanistan, in contrast to the Pentagon story and the mainstream media; (2) The relentless efforts of Obama and the Pentagon to control the public account of this war. While the real war spread geographically and violence intensified, so did the efforts of the United States. to build a positive reading. The examination of the corpses (of foreign occupation forces and innocent Afghan civilians) reveals a situation of exchange. The elites of the countries of the NATO countries have understood that they have entered a dead end and begin to back down

Nineteenth-Century Bahia\u27s Passion for British Salted Cod: From the Seas of Newfoundland to the Portuguese Shops of Salvador\u27s Cidade Baixa, 1822-1914

Dried cod has played a similar role to sugar in the international chain of commerce. It became a major traded commodity between British North America (Newfoundland, Nova Scotia Gaspe) in the nineteenth century. Cheap cod fed the slaves who grew and produced the sugar (and coffee and cotton) which in turn energised the workers of the Industrial Revolution who worked the machines which made the commodities of empire. The machines in factories and their output provided the material basis of Empire. Sugar and cod were important in the cultures of Britain, Newfoundland, the West Indies, West Africa and Brazil. Demand (tastes) and (low) price dictated that salted cod would become a main staple in the West Indies and Brazil even though ample supplies of fresh fish existed locally

The Black Diamonds of Bahia (Carbonados) and the Building of Euro-America: A Half-century Supply Monopoly (1880s-1930s)

This paper traces the birth, maturity and decline of what was Bahia’s natural supply monopoly of black or industrial diamonds: first used in polishing materials (for consumption); then in drilling; and by 1940 they were employed in making parts for the Third Reich’s premier fighter plane, the Messerschmitt bF 109. The evolution in the way these stones were produced, the agents involved in production and distribution, and how the income was distributed along the commodity chain are examined. The importance of technological change is documented with the huge boost in demand for industrial diamonds when the Leschot diamond-head drill was invented (1863). The First World War cut off Bahia from traditional intermediaries and opened up a space for North American capital. A great surge in black diamond production in Bahia was led by the Bandler Corporation of New York, which introduced modern machine-based mining in the late 1920s; but the Great Depression doomed the venture. Between 1931 and 1941, keen secret competition arose to secure access to Bahia’s diamonds between the rising Axis and the Allied powers given the crucial role these stones played in making the modern weapons of war. The first section analyses the emergence of Brazil’s natural monopoly in black diamonds. The second points out the crucial importance technological change (the Leschot diamond-head drill). The next section develops a unique analysis of how earnings were distributed along the black diamond commodity chain at the turn of the twentieth century. The final section underscores how the Great War created a vacuum into which North American capital plunged, such that by the late 1920s for the first time modern machinery was being used for the mass production of black diamonds in Brazil. While the Great Depression frustrated these efforts, the looming Axis and Allied contenders carried out secret schemes to secure Brazil’s black diamonds so central to the execution of modern war

An Excess of Corruption and a Deficit of Toilets: American and Karzai’s Successes in Afghanistan

Afghanistan might be characterized as having a paucity of toilets and an excess of corruption. These two aspects capture the post-Taliban essence of the country. The “achievements” of Hamid Karzai the de facto mayor of Kabul, the United States and NATO in Afghanistan after more than eight years of U.S. occupation and approximately $25 billion in disbursed (2001-9) non-military aid, include Afghanistan being ranked as the worst place in the world for sanitation (per UNICEF data) and in 2009 posting 179th (out of 180 countries) in Transparency International’s corruption-perceptions index. The latter figure for 2005 showed Afghanistan ranking 117th out of 159 countries

THE ROLE OF STREPTOCOCCUS GALLOLYTICUS SUBSPECIES GALLOLYTICUS IN COLON CANCER DEVELOPMENT

Colorectal cancer (CRC) is the third most common cancer in men and women and is also the third most common cause of cancer death. A large body of evidence points towards the possibility that bacteria can have a significant impact on the development of cancer. It has been suggested that Streptococcus gallolyticus subsp. gallolyticus, a group D streptococci, may play a role in the development of CRC. Sg, formerly S. bovis biotype I, has been shown to be highly associated with CRC. In observing patients with either Sg bacteremia or endocarditis it was found that 25-80% of patients with Sg bacteremia had tumors and 18-62% of patients with Sg endocarditis had colonic neoplasias. However, other closely related Streptococcal strains, such as S. pasterianus and S. infantarius, have not been shown to have this strong association with CRC. In fact, it has been shown that biotype I is more often associated with CRC (94%) as compared to biotype II (18%). This knowledge has important clinical implications, and yet little is known about the role of Sg on CRC and the underlying mechanisms. Here we show that mice treated with Sg had significantly more tumors, higher tumor burden and dysplasia grade, and increased cell proliferation and β-catenin level in colonic crypts compared to mice treated with control bacteria. Sg strains that promoted proliferation were also more efficient at adhering to CRC cell lines and colonizing a mouse model. Additionally, in human patients Sg was highly prevalent in CRC patients and tumor tissues had an increased Sg burden in comparison to normal adjacent tissues. These results provide exciting new information and establish a tumor-promoting role of Sg that involves specific bacterial and host factors

The Obama/Pentagon War Narrative, the Real War and Where Afghan Civilian Deaths Do Matter

This article investigates two related issues: (1) the on-the-ground experience of the fierce US war. in Afghanistan, in contrast to the Pentagon story and the mainstream media; (2) The relentless efforts of Obama and the Pentagon to control the public account of this war. While the real war spread geographically and violence intensified, so did the efforts of the United States. to build a positive reading. The examination of the corpses (of foreign occupation forces and innocent Afghan civilians) reveals a situation of exchange. The elites of the countries of the NATO countries have understood that they have entered a dead end and begin to back down