A property of coefficients of variation for ordered bivariate log-normal variables

This paper considers the maximum and minimum of a pair of log-normal variables with equal mean. It shows that either order statistic has a smaller coefficient of variation than the two original log-normal variables provided the latter are of equal variance. When the variances are unequal, as the variance ratio increases, the minimum (maximum), has a smaller coefficient of variation if the correlation coefficient of the log-normal variables is small (small) and the variances are large (small).     

The effect of non-normality on estimating the variance of the combined ratio estimate in complex surveys

The performance of the balanced half-sample, jackknife and linearization methods for estimating the variance of the combined ratio estimate is studied by means of a computer simulation using artificially generated non-normally distributed populations.

The results of this investigation demonstrate that the variance estimates for the combined ratio estimate may be highly biased and unstable when the underlying distributions are non-normal. This is particularly true when the number of observations available from each stratum is small. The jack-     

Some Reflections on the Legacies of Michael White: An Australian Perspective

This article, which appears in a special 30‐year anniversary edition of the Australian and New Zealand Journal of Family Therapy, reflects on the legacies of the work of Michael White. It begins by looking back on Michael's time as editor of the Australian Journal of Family Therapy. Of the many themes that were discussed in the Editorials and Letters to the Editor section of this journal in the early 1980s, this article focuses on three in particular to explore the legacies of the work of Michael White. The author describes how Michael has bequeathed not only a profound body of work, but also a distinctive spirit of originating, and ways of working that consider the effects of social issues and that examine the politics of experience. It is the author's hope that this approach to considering Michael White's legacies honours his work and also honours the contributions of the Australian and New Zealand Journal of Family Therapy in its 30th year.     

Marginal homogeneity,symmetry, and independence

A contingency table of the mc form provides a convenient summary of data when c individuals in a matched set9 each belonging to a different one of c classifications, are identified as belonging to one of m categories, A study in which matched sets (c=3) of 1 case, 1 hospital control, and 1 neighborhood control are classified into one of m=4 occupational categories would be an example, Independence in the cxm tables for each of the matched sets implies symmetry in the summary mc table with consequent marginal homogeneity. Adaptation of the Mantel-Haenszel procedure for testing independence to the case of many cxm tables so as to yield a chi square with (cl)(ml) degrees of freedom (DF) provides a test of marginal homogeneity in the summary mc table. This can be viewed as a test of symmetry directed against alternatives which would make for marginal inhomogeneity and can differ     

Spirituality and child welfare reunification: a narrative analysis of successful outcomes

When children are removed from their families because of maltreatment, the child welfare system seeks reunification whenever possible. Despite the importance of this goal, little is known about families who are able to achieve and maintain successful reunification. This qualitative study conducted in‐depth interviews with 15 families who completed their child welfare case plans, were reunited with their children and remained together for at least 1 year post‐reunification. Narrative analysis using a combination of thematic and structural coding was completed to examine the strengths and process families discussed related to their successful child welfare outcomes. This paper discusses one of those strengths, spirituality, in greater depth. Specifically, 12 participants situated the strength of spirituality within their stories as an important narrative element they perceived as critical, leading to important changes. Findings highlight the benefits some families receive from their spiritual beliefs, practices and faith communities when working towards reunification, suggesting child welfare practitioners be prepared to identify and honour this family strength.     

Oiling the wheels? Flexible labour markets and the migration industry

ABSTRACT

The growing commercialisation of migration, often through a multiplicity of labour market intermediaries, is an issue of increasing academic interest. We seek to contribute to an emerging research agenda on the migration industries by exploring how one of the key actors that constitutes it, recruitment agencies, sits at the nexus between flexible labour market structures and migrant labour. Interviews with U.K. labour providers and low-wage employers form the evidence base for an analysis of the strategies developed by recruiters to derive commercial gain from connecting the so-called ‘supply’ and ‘demand’ sides of the flexible international labour market. We seek to contribute to understandings of the analytical categories within migration systems by illustrating how the migration industry interacts with other key stakeholders to structure international migration.     

A Dynamic Reinterpretation of Nash Bargaining With Endogenous Threats

This paper concerns the two‐stage game introduced in Nash (1953). It formalizes a suggestion made (but not pursued) by Nash regarding equilibrium selection in that game, and hence offers an arguably more solid foundation for the “Nash bargaining with endogenous threats” solution. Analogous reasoning is then applied to an infinite horizon game to provide equilibrium selection in two‐person repeated games with contracts. In this setting, issues about enforcement of threats are much less problematic than in Nash's static setting. The analysis can be extended to stochastic games with contracts.     

Cautious Expected Utility and the Certainty Effect

Many violations of the independence axiom of expected utility can be traced to subjects' attraction to risk‐free prospects. The key axiom in this paper, negative certainty independence ([Dillenberger, 2010]), formalizes this tendency. Our main result is a utility representation of all preferences over monetary lotteries that satisfy negative certainty independence together with basic rationality postulates. Such preferences can be represented as if the agent were unsure of how to evaluate a given lottery p; instead, she has in mind a set of possible utility functions over outcomes and displays a cautious behavior: she computes the certainty equivalent of p with respect to each possible function in the set and picks the smallest one. The set of utilities is unique in a well defined sense. We show that our representation can also be derived from a “cautious” completion of an incomplete preference relation.     

Competition and Coordination in a Two‐Channel Supply Chain

We study competition and coordination in a supply chain in which a single supplier both operates a direct channel and sells its product through multiple differentiated retailers. We study analytically the supply chain with symmetric retailers and find that the supplier prefers to have as many retailers as possible in the market, even if the retailers' equilibrium retail price is lower than that of the supplier, and even if the number of retailers and their cost or market advantage prevent sales through the direct channel. We find that the two‐channel supply chain may be subject to inefficiencies not present in the single‐channel supply chain. We show that several contracts known to coordinate a single‐channel supply chain do not coordinate the two‐channel supply chain; thus we propose a linear quantity discount contract and demonstrate its ability to perfectly coordinate the two‐channel supply chain with symmetric retailers. We provide some analytical results for the supply chain with asymmetric retailers and propose an efficient solution approach for finding the equilibrium. We find numerically that the supplier still benefits from having more retailers in the market and that linear quantity discount contracts can mitigate supply chain inefficiency, though they no longer achieve perfect coordination.