bluuebunny/crossref_metadata_2025_split huggingface dataset:
Using Quantile Averages in Matched Observational Studies
Authors: Rosenbaum Paul R. 
Published: March 2003

SUMMARY
In two observational studies, one investigating the effects of minimum wage laws on employment and the other of the effects of exposures to lead, an estimated treatment effect’s sensitivity to hidden bias is examined. The estimate uses the combined quantile averages that were introduced in 1981 by B. M. Brown as simple, efficient, robust estimates of location admitting both exact and approximate confidence intervals and significance tests. Closely related to Gastwirth’s estimate and Tukey’s trimean, the combined quantile average has asymptotic efficiency for normal data that is comparable with that of a 15% trimmed mean, and higher efficiency than the trimean, but it has resistance to extreme observations or breakdown comparable with that of the trimean and better than the 15% trimmed mean. Combined quantile averages provide consistent estimates of an additive treatment effect in a matched randomized experiment. Sensitivity analyses are discussed for combined quantile averages when used in a matched observational study in which treatments are not randomly assigned. In a sensitivity analysis in an observational study, subjects are assumed to differ with respect to an unobserved covariate that was not adequately controlled by the matching, so that treatments are assigned within pairs with probabilities that are unequal and unknown. The sensitivity analysis proposed here uses significance levels, point estimates and confidence intervals based on combined quantile averages and examines how these inferences change under a range of assumptions about biases due to an unobserved covariate. The procedures are applied in the studies of minimum wage laws and exposures to lead. The first example is also used to illustrate sensitivity analysis with an instrumental variable.
Correspondence Analysis of Square Asymmetric Matrices
Authors: Greenacre Michael 
Published: March 2003

SUMMARY
The application of correspondence analysis to square asymmetric tables is often unsuccessful because of the strong role played by the diagonal entries of the matrix, obscuring the data off the diagonal. A simple modification of the centring of the matrix, coupled with the corresponding change in row and column masses and row and column metrics, allows the table to be decomposed into symmetric and skew symmetric components, which can then be analysed separately. The symmetric and skew symmetric analyses can be performed by using a simple correspondence analysis program if the data are set up in a special block format. The methodology is demonstrated on a social mobility table from the first democratically elected Parliament in Germany, the Frankfurter Nationalversammlung. The table cross-tabulates the jobs of parliamentarians when first entering the labour market and their jobs in May 1848 when the Parliament started its first session.
Investigating Excess Returns from Nominal Bonds*
Authors: Breedon Francis , Chadha Jagjit S. 
Published: March 2003

AbstractEstimated real returns on nominal bonds show excess returns of some 200 bp over their index‐linked equivalent. This paper considers two possible explanations for this large difference. First, we assess the likely inflation risk premium by calibrating a model of optimal bond prices under uncertainty. Employing either of CRRA or Abel (1990) relative consumption utility function to derive the stochastic discount factor and covariation risk, we suggest that the inflation risk component of this excess return is unlikely to be much above 50 bp. Secondly, we find little evidence that these excess returns can be ascribed to consistent expectational errors in predicting inflation.
Straddling the Divides: Remaking Associational Life in the Informal African City
Authors: Simone Abdoumaliq 
Published: March 2003

Actors in fluid African urban environments endeavor to construct effective means to generate collaborative social action, enforce collective responsibility, and deploy effective and legitimate instruments of power. This effort configures an uneasy tension between the adoption of normative discourses of urban management and governance, and the proliferation of more provisional and informal modalities of association. The article treats informalization as a dynamic process related to new challenges faced by urban citizens in their attempts to access opportunities and, at the same time, maintain social coherence. It explores a broad range of tactics and institutions being used to access livelihood opportunities that more often are now external to the quarter, while maintaining some functional sense of local solidarity.Les acteurs intervenant dans l'incertitude des contextes urbains africains s'efforcent d'élaborer des moyens efficaces pour générer des collaborations d'action sociale, faire valoir une responsabilité collective, et déployer des instruments de pouvoir performants et légitimes. Cette entreprise crée un malaise entre les discours normatifs adoptés par l'autorité et l'encadrement urbains, et la prolifération de modalités d'association provisoires et informelles. L'article traite de ‘l'informalisation’ en tant que processus dynamique dans le cadre des nouveaux défis que les citoyens urbains rencontrent dans leurs tentatives d'accéder à des opportunités tout en préservant la cohérence sociale. Il explore un large éventail de tactiques et institutions utilisées pour obtenir des possibilités de subsistance – désormais plus souvent extérieures au quartier – et protéger parallèlement un certain sens fonctionnel de solidarité locale.
International Trade, Labour Migrations and Capital Flows: Long‐Term Evidence for Australia, Canada, the United Kingdom and the United States
Authors: Clarke Harry 
Published: March 2003

The historical links between international factor mobility and the extent of international trade are analysed over the long term for three high labour immigration countries (Australia, Canada and the United States) and one high labour emigration country (the United Kingdom).Time series data are used. Current international openness is assessed relative to this experience. International factor market integration has increased over time with trade liberalization, suggesting that traditional Hecksher‐Ohlin thinking cannot be readily used to account for long‐term trends in several important economies.Both trade and factor mobility have an episodic character that makes it misleading to assess current international openness only in terms of post‐World War 2 economic trends.
Return Migration to Jamaica and its Development Potential
Authors: Thomas‐Hope Elizabeth 
Published: March 2003

Return migration to Jamaica is associated closely with the existence and nature of the transnational linkages established between migrants and their home country, especially at the level of the household and family. Remittances invariably precede, accompany and follow the actual return of migrants and comprise money as well as a range of consumer goods.Data on the number of returning migrants to Jamaica have been collected officially only since 1992; other information is derived from field studies. The figures show that the US is the source of most return migrants to Jamaica, with the United Kingdom second.Likewise, there are few official statistics on remittances, especially of those entering the country through informal channels. Nevertheless, data on the receipt of money through the Bank of Jamaica, indicate that during the 1990s remittances as a percentage of GDP exceeded that of the traditional foreign currency earners of bauxite and sugar.Growing awareness of the potential of the Jamaican overseas community has led the Government of Jamaica to establish programmes, including The Return of Talent programme, supported by the International Organization for Migration (IOM), to encourage the return of nationals.Different types of return migrants have the potential to make different kinds of contributions to national development – some through their skills, educational and professional experience, others through the financial capital which they transfer for investment or as retirement income. However, the most significant development potential of return lies in the social and economic conditions in Jamaica itself. If confidence levels are high, there will be little difficulty in attracting persons to return and financial transfers and investments will increase. Furthermore, the social and economic environment largely conditions the extent to which skills and talent as well as the financial capital are effectively utilized.
On the History and Selectivity of Turkish and Moroccan Migration to Belgium
Authors: Reniers Georges 
Published: March 2003

The classic image of the labour migrant arriving in Western Europe in the 1960s and 1970s is one of an unskilled individual exchanging a life of work on the land for one of manual labour in industry.For Turks and Moroccans, in particular, the image of an undifferentiated immigrant labour force is reinforced by the commencement of migration from both countries during the same period of high labour demand, their common religious beliefs and the similar legal frameworks under which they applied to gain access to European society.This oversimplified image of an uneducated and undifferentiated migrating labour force is challenged in this article through the concept of selectivity. By using a combination of different data sources, a systematic comparison is made of leavers and stayers with respect to their region of origin and educational attainment. The (self‐) selection of the immigrants is, in other words, the empirical angle that is chosen to compare and characterize both migration systems.In bringing selection to the forefront, we explicitly focus on a topic other migration theories often have difficulties incorporating, i.e., explaining whysome people in a given country or region migrate and others do not. While Turkish and Moroccan migration overlap only partly in their nature, variances suggest a different logic underlying each. Two concepts of Petersen (conservative and innovative migration) are borrowed to characterize the two migration systems and to interpret differences observed in the selection of immigrants. The advantage of this typology is that it explicitly accounts for migration motives and migrants’ aspirations. This enables us to understand and formulate hypotheses with respect to the further evolution of both migration systems under the current context of legally restricted migration opportunities and also helps explain different integration strategies into the host society.Implicit in this article is a plea for the added value of the empirical operationalization of selectivity in terms of understanding migration systems. However, such an approach requires comparable data on the sending and receiving countries. In this case, data were combined from two national surveys conducted in Belgium between 1994 and 1996, with aggregated data from national statistical institutes of the sending countries, for the analysis of selection with respect to the region of origin. The same survey data were used in combination with the DHS surveys for Morocco (1992) and Turkey (1993) for the analysis of selection with respect to educational level.
Europe and the Immigration of Highly Skilled Labour
Authors: Mahroum Sami 
Published: March 2003

The competition for highly skilled labour continues to be fierce and is taking a more institutionalized pattern across most of the developed world. This article sketches the changes in policies, legislations, and procedures across various EU countries and compares these with those of other developed countries.The article shows that EU member states not only compete with non‐EU countries and regions but also among themselves in order to attract and maintain sufficient flows of highly skilled labour.
Regional Organizations and Intra‐Regional Migration in Sub‐Saharan Africa: Challenges and Prospects
Authors: Adepoju Aderanti 
Published: March 2003

Africa is a region of diverse migration circuits relating to origin, destination and transit for labour migrants, undocumented migrants, refugees and brain circulation of professionals.This article outlines major migration configurations in the region, and the role of two vibrant subregional organizations — Economic Community of West African States and South African Development Community — in facilitating, containing or curtailing intra‐regional migration which takes place within diverse political, economic, social and ethnic contexts; the transformation of brain drain into brain circulation; and commercial migration in place of labour migration within the region.Despite overlapping membership, wavering political support, a poor transportation network, border disputes and expulsions, these subregional organizations are crucial for the region's collective integration into the global economy, and to enhance economic growth and facilitate labour intraregional migration.Free movement of persons without visa, adoption of ECOWAS travellers' cheques and passports, the creation of a borderless Community; and the granting of voting rights and later citizenship and residence permits by South Africa to migrant workers from SADC countries are positive developments.These organizations need to foster cooperation between labour‐exporting and recipient countries, implement the protocols on the right of residence and establishment; promote dialogue and cooperation in order to harmonize, coordinate and integrate their migration policies as envisioned by the 1991 Abuja Treaty establishing the African Economic Community.
Expressed emotion, attributions and depression in mothers of children with problem behaviour
Authors: Bolton Catherine , Calam Rachel , Barrowclough Christine , Peters Sarah , Roberts Janine , Wearden Alison , Morris Julie 
Published: March 2003

Background: This was an initial study seeking to examine the relationship between Expressed Emotion (EE), spontaneous causal attributions and depression in mothers of children referred for problem behaviour.Method: Sixty‐one mothers were interviewed using the Camberwell Family Interview (CFI). The CFI was coded for maternal EE and spontaneous causal attributions regarding the child's behaviour. Self‐report measures of child problem behaviour and maternal depressive symptoms were also completed.Results: Consistent with previous research, high EE mothers, compared to low EE mothers, were more likely to make attributions that judged the cause of problem behaviour to be personal to and controllable by the child and also made more ‘child‐blaming’ attributions than low EE mothers. Mothers’ scores on the Beck Depression Inventory were found to be associated with ‘child‐blaming’ attributions and higher levels of EE. Regression analyses did not support the hypothesised role of attributions as a mediator between depression and EE but did identify EE as a potential mediator in the relationship between maternal depressed mood and ratings of child problem behaviour.Conclusions: These results indicate the relevance of both EE and attributions in mothers of children with problem behaviour and suggest that maternal depressed mood is an important factor which is related to both of these.
Do Mandatory Hedge Disclosures Discourage or Encourage Excessive Speculation?
Authors: Sapra Haresh 
Published: March 2003

In order to shed some light on the desirability of hedge disclosures, I investigate the consequences of hedge disclosures on a firm’s risk management strategy. Several major results emerge from this analysis. First, greater transparency about a firm’s derivative activities is not necessarily a panacea for imprudent risk management strategies. I show that such transparency actually induces the firm to take excessive speculative positions in the derivative market. Second, I show that the firm may choose a prudent risk management strategy in the absence of hedge disclosures. However, the selection of a prudent risk management comes at a cost. The firm’s production policy is distorted in the absence of hedge disclosures.These findings suggest that regulators must carefully investigate the trade‐offs between production distortions and risk management distortions in evaluating the desirability of mandatory hedge disclosures for all firms.
Explaining Monday Returns
Authors: Draper Paul , Paudyal Krishna 
Published: March 2003

AbstractThe Monday effect is reexamined using two stock indexes and a sample of 452 individual stocks that trade on the London Stock Exchange. The results based on conventional test methods reveal a negative average return on Monday. Extending the analysis to examine the effects of various possible influences simultaneously, the average Monday return becomes positive and does not differ significantly from the average returns of most other days of the week. Fortnight, ex‐dividend day, account period, (bad) news flow, trading activity, and bid‐ask spread effects are all controlled for. The results broadly support the trading time hypothesis.
An Analysis of Nonunderwritten Rights Offers: The Case of Closed‐END Funds
Authors: Miles James A. , Peterson Mark A. 
Published: March 2003

AbstractWe study nonunderwritten rights offerings without subscription pre‐commitments from large shareholders. The results indicate firms incur substantial indirect costs in the form of price concessions for raising equity capital this way. The data therefore support the selling cost explanation of the rights‐offering paradox. Additionally, we describe how market participants collectively respond to intermediate such offerings.
EFD: A Hybrid Knowledge/Statistical‐Based System for the Detection of Fraud
Authors: Major John A. , Riedinger Dan R. 
Published: March 2003

AbstractElectronic Fraud Detection (EFD) assists Investigative Consultants in the Managed Care & Employee Benefits Security Unit of The Travelers Insurance Companies in the detection and preinvestigative analysis of health care provider fraud. The task EFD performs, scanning a large population of health insurance claims in search of likely fraud, has never been done manually. Furthermore, the available database has few positive examples. Thus, neither existing knowledge engineering techniques nor statistical methods are sufficient for designing the identification process. To overcome these problems, EFD uses knowledge discovery techniques on two levels. First, EFD integrates expert knowledge with statistical information assessment to identify cases of unusual provider behavior. The heart of EFD is 27 behavioral heuristics, knowledge‐based ways of viewing and measuring provider behavior. Rules operate on them to identify providers whose behavior merits a closer look by the investigative consultants. Second, machine learning is used to develop new rules and improve the identification process. Pilot operations involved analysis of nearly 22,000 providers in six metropolitan areas. The pilot is implemented in SAS Institute's SAS System, AICorp's Knowledge Base Management System, and Borland International's Turbo Prolog.
In Silico Pattern-Based Analysis of the Human Cytomegalovirus Genome
Authors: Rigoutsos Isidore , Novotny Jiri , Huynh Tien , Chin-Bow Stephen T. , Parida Laxmi , Platt Daniel , Coleman David , Shenk Thomas 
Published: March 2003

ABSTRACT

More than 200 open reading frames (ORFs) from the human cytomegalovirus genome have been reported as potentially coding for proteins. We have used two pattern-based in silico approaches to analyze this set of putative viral genes. With the help of an objective annotation method that is based on the Bio-Dictionary, a comprehensive collection of amino acid patterns that describes the currently known natural sequence space of proteins, we have reannotated all of the previously reported putative genes of the human cytomegalovirus. Also, with the help of MUSCA, a pattern-based multiple sequence alignment algorithm, we have reexamined the original human cytomegalovirus gene family definitions. Our analysis of the genome shows that many of the coded proteins comprise amino acid combinations that are unique to either the human cytomegalovirus or the larger group of herpesviruses. We have confirmed that a surprisingly large portion of the analyzed ORFs encode membrane proteins, and we have discovered a significant number of previously uncharacterized proteins that are predicted to be G-protein-coupled receptor homologues. The analysis also indicates that many of the encoded proteins undergo posttranslational modifications such as hydroxylation, phosphorylation, and glycosylation. ORFs encoding proteins with similar functional behavior appear in neighboring regions of the human cytomegalovirus genome. All of the results of the present study can be found and interactively explored online (
http://cbcsrv.watson.ibm.com/virus/
).
Consistency and Akrasia in Plato's Protagoras
Authors: Woolf Raphael 
Published: February 2003

AbstractRelatively little attention has been paid to Socrates' argument against akrasia in Plato's Protagoras as an example of Socratic method. Yet seen from this perspective the argument has some rather unusual features: in particular, the presence of an impersonal interlocutor ("the many") and the absence of the crisp and explicit argumentation that is typical of Socratic elenchus. I want to suggest that these features are problematic, considerably more so than has sometimes been supposed, and to offer a reading of the argument that accounts for them. My reading revolves around the connections between Socratic method, consistency and akrasia. I argue that Socrates' discussion of akrasia aims at exposing the interlocutor's inconsistency, and to this extent is typical of Socratic inquiry; but it is also untypical, insofar as Socrates' chief concern here is with the inconsistency between an interlocutor's statements and his actions (what I call "word-deed inconsistency") rather than, as more usually, inconsistency among an interlocutor's various statements ("word-word inconsistency"). I use this reading to show how the akrasia argument, despite its untypical features, is not just a variant, but in an important way a paradigm, of Socratic method.
A Platonic Cento in Cicero
Authors: Glucker John 
Published: February 2003

AbstractDe Divinatione 1.115 has been ascribed in the past to Posidonius, to 'a Pythagoreanizing Posidonius', or to 'the Stoics'. Its emphasis on the soul's eternity and knowledge of 'all things in Hades and on earth' precludes such sources. I point out that the passage contains clear reminiscences of the myth of transmigration and αναμνησις in Meno and of a passage in the myth of Er, probably combining them with Republic 571-2. No philosopher or school known to us could be Cicero's source for such a combination, taking, as it does, such details of the Platonic myths as literal truths. I suggest that Cicero's source for this passage was some contemporary or slightly earlier 'Pythagoreanizing Platonist', whose identity can no longer be established.