Semi-parametric estimation of joint large movements of risky assets

The classical approach to modelling the occurrence of joint large movements of asset returns is to assume multivariate normality for the distribution of asset returns. This implies independence between large returns. However, it is now recognised by both academics and practitioners that large movements of assets returns do not occur independently. This fact encourages the modelling joint large movements of asset returns as non-normal, a non trivial task mainly due to the natural scarcity of such extreme events. This paper shows how to estimate the probability of joint large movements of asset prices using a semi-parametric approach borrowed from extreme value theory (EVT). It helps to understand the contribution of individual assets to large portfolio losses in terms of joint large movements. The advantages of this approach are that it does not require the assumption of a specific parametric form for the dependence structure of the joint large movements, avoiding the model misspecification; it addresses specifically the scarcity of data which is a problem for the reliable fitting of fully parametric models; and it is applicable to portfolios of many assets: there is no dimension explosion. The paper includes an empirical analysis of international equity data showing how to implement semi-parametric EVT modelling and how to exploit its strengths to help understand the probability of joint large movements. We estimate the probability of joint large losses in a portfolio composed of the FTSE 100, Nikkei 250 and S&P 500 indices. Each of the index returns is found to be heavy tailed. The S&P 500 index has a much stronger effect on large portfolio losses than the FTSE 100, although having similar univariate tail heaviness

Collaborative learning using Microworld and WebMapQuest

The intention of this paper is to show relevant issues (resulting from theoretical and empiric research) about how Microworld can be used to elicit the building of knowledge and to encourage collaborative learning. For that purpose, we have been investigating how to manage information overflow and develop incentives to collaborative learning using Microworld through WebMapQuest - projects of investigation with virtual maps. In this paper, a brief conceptual approach is discussed, major contributions difficulties and future trends are presented

Global aging: emerging challenges

This repository item contains a single issue of The Pardee Papers, a series papers that began publishing in 2008 by the Boston University Frederick S. Pardee Center for the Study of the Longer-Range Future. The Pardee Papers series features working papers by Pardee Center Fellows and other invited authors. Papers in this series explore current and future challenges by anticipating the pathways to human progress, human development, and human well-being. This series includes papers on a wide range of topics, with a special emphasis on interdisciplinary perspectives and a development orientation.Aging policy frameworks were devised during a demographic and economic context in which population aging seemed confined to wealthy nations. These countries could afford retirement policies that supported older workers, decreased unemployment among younger workers, and decreased family pressure to provide old age care. This calculation was based in part on failure to anticipate three demographic trends: continual decline in fertility below replacement rate, continual gains in longevity, and the rise of population aging in poor and “under-developed” countries. These three trends now fuel a sense of crisis. In the global North, there is fear that increasing numbers of older adults will deplete state pension and health care systems. In the global South, the fear is that population aging coupled with family breakdown” requires such state intervention. Natural disaster metaphors, such as “agequake” and “age-tsunami,” illustrate fears of a “graying globe” in which population aging implies population decay and economic destruction. Yet, global aging trends develop over decades and are not easily reversed. Longer-range trends can be addressed through revising policy frameworks to incorporate how growing old is moving from global exception to expectation. Alexandra Crampton was a 2008–2009 Postdoctoral Fellow at the Frederick S. Pardee Center for the Study of the Longer-Range Future and is currently Assistant Professor in the Department of Social and Cultural Sciences at Marquette University. Her scholarship and teaching bring an anthropological perspective to theoretical and practical questions on aging, social welfare policy, social work practice, negotiation, and alternative dispute resolution. She has presented her work for the American Anthropological Association, the Gerontological Society of America, the Council on Social Work Education, and the Society for Social Work Research. She holds a joint PhD in Social Work and Anthropology from the University of Michigan

The Effect of Hawaii’s Vast Diversity on Racial and Social Prejudices

Food is the universal language of the world, and Hawaiians speak SPAM. Hawaii is the largest consumer of SPAM in the world, with their own signature recipe, as well as an annual SPAM party which over 20,000 people attend. Hawaiian locals cannot get enough of the stuff, consuming more than 5 million pounds year. SPAM is just one of many beloved foods in Hawaii, all of which are from different cultures. Residents have access to Chinese rice and stir fry, Korean kimchi and marinated meats, Japanese sashimi and bento boxes, Portuguese tomatoes and chili peppers, Puerto Rican casseroles and pasteles, Filipino sweet potatoes and adobo, American macaroni salad and hamburgers, and Hawaiian taro and kalua pig. Food is just one aspect of a very mixed culture that borrows food, music, religion, and customs that are used every day. Diversity is not tolerated, but embraced in Hawaii

Practical activities to enhance L2 identity

How strong is your students' sense of L2 identity? Can enhancing L2 identity motivate learners to engage more profoundly and enduringly with English? The purpose of this practical guide is to demonstrate how we can increase L2 learner motivation by inviting students to think about who they are, how they are perceived by others, and who they would like to be. These activities are aimed at practitioners who teach L2 English. The tasks invite students to draw pictures representing their own minds, create hierarchies and word lists. The drawings, for example, are revealing about the importance of our language learning centres within a framework of personal individual tastes

Effects on the reproductive system in domestic dowl (Gallus domesticus) after embryonic exposure to estrogenic substances

Environmental pollutants with estrogenic activity have a potential to disrupt oestrogen-dependent developmental processes. Thus, the aim of this thesis was to investigated how embryonic exposure to the estrogenic pollutants EE2 (17 alpha- ethynyloestradiol) and o,p´-DDT (1-[2-chlorophenyl]-1-[4-chlorophenyl]-2,2,2-trichloro-ethane) affects the reproductive system in the domestic hen (Gallus domesticus). Hens exposed in ovo to 20 or 60 ng EE2/g egg or 37 or 75 micro g o,p´-DDT/g egg produced a normal number of eggs but with thinner shells as adults. These hens also showed a reduction of shell gland capillaries with carbonic anhydrase (CA) activity. CA is considered a key enzyme in shell formation and the developmentally induced disruption of this enzyme may explain the observed eggshell thinning. Left oviduct and infundibulum was shortened in exposed hens and severely malformed in hens exposed to 150 or 300 micro g o,p´-DDT/g egg, which likely explained the inhibited egg production in these birds. Semen output was significantly reduced in both o,p´-DDT and EE2 exposed roosters, whereas sperm quality was unaffected. The left testis was deformed with an atrophied epididymis. Altered plasma inhibin concentration and histological evaluation implied a disturbed Sertoli cell function resulting in reduced germ cell production. Structural malformations in the epididymis indicating disrupted fluid transfer and transport of spermatozoa are possible contributors to the reduced semen output. Exposure to o,p´-DDT resulted in a wider range of effects than EE2 such as feminisation of the cloaca at hatch, cloacal deformation in adult roosters and a reduced comb weight, while hens showed retained right oviducts. Right spur diameter was affected by both substances.Localisation of epididymal progesterone receptors and cytoplasmic and membrane associated oestrogen receptor alfa in late spermatids, spermatozoa and epididymal tissues were novel findings in rooster. Embryonic exposure of domestic fowl to o,p´-DDT or EE2 resulted in persistent malformations of the reproductive organs of both sexes, with eggshell thinning and reduced semen production as a consequence. The results provide a possible explanation for how eggshell thinning may be induced in wild birds and show that also male birds may suffer from reduced reproductive success due to oestrogen-like pollutants

The Collective Building of Knowledge in Collaborative Learning Environments

The intention of this chapter is to investigate how collaborative learning environments (CLEs) can be used to elicit the collective building of knowledge. This work discusses CLEs as lively cognitive systems and looks at some strategies that might contribute to the improvement of significant pedagogical practices. The study is supported by rhizome principles, whose characteristics allow us to understand the process of selecting and connecting what is relevant and meaningful for the collective building of knowledge. A brief theoretical and conceptual approach is presented and major contributions and difficulties about collaborative learning environments are discussed. New questions and future trends about the collective building of knowledge are suggested