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Are asthma and allergies more common in adolescents conceived with assisted reproductive technologies (ART) compared with adolescents conceived without?The Growing Up Healthy Study (GUHS) is a prospective cohort study including ART-conceived offspring born between 1991 and 2001 in Perth, Australia. Their long-term health outcomes, including asthma and allergy parameters, were compared with those of their counterparts conceived without ART from the Raine Study Generation 2 (Gen2), born in 1989-1991. At age 14, 152 GUHS and 1845 Gen2 participants completed the following assessments: the International Studies of Asthma and Allergies in Childhood (ISAAC) questionnaire, spirometry, methacholine challenge testing and skin prick testing (SPT).No differences were detected in the prevalence of current asthma (7.7% versus 10.8%, adjusted odds ratio [aOR] 0.82 (95% CI 0.44-1.52), P = 0.530). Spirometry-measured lung volumes were larger in the ART adolescents. Bronchial hyperresponsiveness was less prevalent in the ART cohort (8.8 versus 18.6%, P = 0.006). Current allergic rhinoconjunctivitis (ARC) rates were significantly higher in the ART cohort (32.4% versus 25.2%, aOR 1.52 [95% CI 1.03-2.26], P = 0.036), with no cohort differences in atopic dermatitis. Food allergies were more prevalent in the ART cohort (20.7 versus 10.9%, aOR 1.89 [95% CI 1.17-3.06], P = 0.010) with more adolescents having a positive SPT (68.0% versus 45.4%, aOR 3.03 [95% 1.99-4.63], P0.001).This study reports no differences in asthma prevalence, slightly altered lung function, an increase in ARC, food allergies and positive SPT in the ART-conceived adolescents. These findings are important to families and healthcare providers and may open up possibilities for targeted screening and treatment. Further studies are required to confirm these findings.

A sofic group $G$ is said to be flexibly stable if every sofic approximation to $G$ can converted to a sequence of disjoint unions of Schreier graphs by modifying an asymptotically vanishing proportion of edges. We establish that if $\mathrm{PSL}_d(\mathbb{Z})$ is flexibly stable for some $d \geq 5$ then there exists a group which is not sofic., Improvements made based on referee's comments

This paper concerns the study of the global structure of measure-preserving actions of countable groups on standard probability spaces. Weak containment is a hierarchical notion of complexity of such actions, motivated by an analogous concept in the theory of unitary representations. This concept gives rise to an associated notion of equivalence of actions, called weak equivalence, which is much coarser than the notion of isomorphism (conjugacy). It is well understood now that, in general, isomorphism is a very complex notion, a fact which manifests itself, for example, in the lack of any reasonable structure in the space of actions modulo isomorphism. On the other hand, the space of weak equivalence classes is quite well behaved. Another interesting fact that relates to the study of weak containment is that many important parameters associated with actions, such as the type, cost, and combinatorial parameters, turn out to be invariants of weak equivalence and in fact exhibit desirable monotonicity properties with respect to the pre-order of weak containment, a fact that can be useful in certain applications. There has been quite a lot of activity in this area in the last few years, and our goal in this paper is to provide a survey of this work.

We introduce a notion of strategies based on averaging for nonlocal games in quantum information theory. These so-called statistical strategies come in a commuting type and a more specific spatial type, which are respectively special cases of the quantum commuting and quantum spatial strategies commonly considered in the field. We prove a theorem that the sets of statistical commuting strategies and statistical spatial strategies are respectively equal to the sets of quantum commuting strategies and quantum spatial strategies for any nonlocal game. Thus we are able to use the recent negative solution of Tsirelson's problem to obtain a statistical analog showing that there exists a nonlocal game where the set of statistical commuting strategies properly contains the closure of the set of statistical spatial strategies. The proof of this theorem involves development of statistical replicas for numerous constructions in quantum information theory, in particular for the Fourier-type duality between observation structures and dynamical structures. The main point of the argument is to apply the established theory of approximating unitary representations of countable discrete groups by ergodic measure preserving actions of such groups. We note that the relevant groups are nonamenable. We also give an explicit description of a statistical strategy to win the CHSH game from Aspect's experiment with a probability exceeding the maximum possible value for a classical strategy., Published version; https://link.springer.com/article/10.1007/s40509-022-00269-x

This article provides a statistical picture of the economic well-being of Canadian children. We discuss changes in families, nationally and by province. We outline how Canadian policy in support of children has changed and how it differs across regions. Changes or differences in median incomes, in income distributions and in child poverty both before and after taxes and transfers, at different points of time, in different kinds of families, and in different provinces constitute the core of the article. Finally, the economic well-being of Canadian children in 2010 is compared with that of children in eight other affluent countries.

This paper studies certain aspects of harmonic analysis on nonabelian free groups. We focus on the concept of a positive definite function on the free group and our primary goal is to understand how such functions can be extended from balls of finite radius to the entire group. Previous work showed that such extensions always exist and we study the problem of simultaneous extension of multiple positive definite functions. More specifically, we define a concept of 'relative energy' which measures the proximity between a pair of positive definite functions, and show that a pair of positive definite functions on a finite ball can be extended to the entire group without increasing their relative energy. The proof is analytic, involving differentiation of noncommutative Szego parameters., Comment: Published version; https://link.springer.com/article/10.1007/s43034-022-00189-2

Let $G$ be a countable discrete sofic group. We define a concept of uniform mixing for measure-preserving $G$-actions and show that it implies completely positive sofic entropy. When $G$ contains an element of infinite order, we use this to produce an uncountable family of pairwise nonisomorphic $G$-actions with completely positive sofic entropy. None of our examples is a factor of a Bernoulli shift., This version has been revised in accordance with the referee's comments. To appear in Journal d'Analyse Mathematique

Amos Nevo established the pointwise ergodic theorem in $L^p$ for measure-preserving actions of $\mathrm{PSL}_2(\mathbb{R})$ on probability spaces with respect to ball averages and every $p>1$. This paper shows by explicit example that Nevo's Theorem cannot be extended to $p=1$., 4 figures added

We provide the first direct comparisons of poverty and inequality in the North (i.e. Yukon, Northwest Territories, Nunavut) with elsewhere in Canada. We do so by first constructing a northern equivalence scale. Based on an Engel methodology, we estimate the extra income needed by families in the North to devote the same share to necessities as those in southern Canada. Using econometric techniques and public use microdata from the Survey of Household Spending, we find that cost of living is 1.46 times higher in the North. We use this scale to adjust the incomes of northern residents so that purchasing power is, for the purposes of our model, equal to that in the South. We subsequently measure poverty and inequality in northern versus southern Canada over the period 1997–2009. Our findings indicate that incidence of poverty is much higher in the North. For example, 31.1% of northern families with children are poor, compared with 9.9% in the South. Moreover, while approximately 10% of the southern populatio...

We show that weak containment of free ergodic measure- preserving actions of F ∞ \mathbb {F}_\infty is not equivalent to weak containment of the corresponding Koopman representations. This result is based on the construction of an invariant random subgroup of F ∞ \mathbb {F}_\infty which is supported on the maximal actions.

We study an invariant of dynamical systems called naive entropy, which is defined for both measurable and topological actions of any countable group. We focus on nonamenable groups, in which case the invariant is two-valued, with every system having naive entropy either zero or infinity. Bowen has conjectured that when the acting group is sofic, zero naive entropy implies sofic entropy at most zero for both types of systems. We prove the topological version of this conjecture by showing that for every action of a sofic group by homeomorphisms of a compact metric space, zero naive entropy implies sofic entropy at most zero. This result and the simple definition of naive entropy allow us to show that the generic action of a free group on the Cantor set has sofic entropy at most zero. We observe that a distal $\Gamma$-system has zero naive entropy in both senses, if $\Gamma$ has an element of infinite order. We also show that the naive entropy of a topological system is greater than or equal to the naive measure entropy of the same system with respect to any invariant measure., Comment: 19 pages

The Territorial North (i.e. Yukon, Northwest Territories, Nunavut) is markedly different from the rest of Canada; yet there is little statistically reliable information about adolescent well-being in the region. The objective of this paper is to create a portrait of adolescent well-being in the Territorial North relative to Southern Canada. We do so using the Canadian Community Health Survey, a nationally representative dataset. We examine seven domains of well-being with 23 indicators by region and Aboriginal identity for youth aged 12 to 17. We include objective and subjective measures, reflecting the importance of adolescents’ perspectives in studies of their own well-being. We find negligible differences among the non-Aboriginal population; while most indicators are substantially worse for Aboriginal youth, especially in Northern Canada (e.g. income, poverty, household education, family structure, crowding, food insecurity, exposure to second-hand smoke, school enrolment, smoking, sexual activity, obesity and overweight, oral and mental health). However, there are exceptions (e.g. physical activity, fruit and vegetable consumption, stress, body image, belonging). Nevertheless, Aboriginal youth in the North are generally less satisfied with life. This is not surprising since they fare worse in most well-being indicators considered in this study.

This paper uses longitudinal microdata from the Statistics Canada National Longitudinal Survey of Children and Youth (NLSCY) to study the family income dynamics of Canadian children from the time they are 4 or 5 until they are 14 or 15. Dynamics of family income have been studied less often than dynamics of child poverty. Yet we argue that from the perspective of equity, it is important to know the extent to which some children are always affluent while other children are always poor. Also, since our social safety net is designed to shelter Canadians, including children, from both economic hardship and economic loss, it is also important, from the perspective of policy, to assess risk factors for persistent low income as well as correlates of major economic loss.

We ask how the paid work of Canadian married mothers and fathers is affected when a child has a physical/mental condition or health problem that leads to restrictions in daily activities. Using the Statistics Canada National Longitudinal Survey of Children and Youth, we find that married mothers of children with disabilities are less likely to engage in paid work and/or work fewer paid hours per week. No statistically significant changes in paid work participation or hours are apparent for fathers of the same children. We find, moreover, evidence that the degree of specialization within families increases when there is a child with a disability. These responses are consistent with traditional gender roles within families, and may make sense as a ‘household’ coping strategy. However, such a division of labor may generate economic vulnerability for mothers compared to fathers.

In this paper, we ask whether there are Canada/U.S. differences in the extent to which children who were rich versus poor during their early years have developed differences in outcomes by the time they reach adolescence or early adulthood. Using comparable longitudinal data for each country, separate analyses are first conducted for rich compared to poor children living in Canada and rich compared to poor children living in the United States. We then pool data sets to test whether any rich/poor child outcome gaps that have emerged are greater (or smaller) in Canada compared to the U.S. Our data source for Canada is the Statistics Canada National Longitudinal Survey of Children and Youth and for the U.S. we use the National Longitudinal Survey of Youth 79, Child-Young Adult supplement. Key findings include: 1) rich child/poor child outcome gaps are evident for all outcomes in both countries; 2) larger gaps between rich and poor children are evident in the U.S. for math scores and high school completion.

Antigenic variation enables pathogens to avoid the host immune response by continual switching of surface proteins. The protozoan blood parasite Trypanosoma brucei causes human African trypanosomiasis (“sleeping sickness”) across sub-Saharan Africa and is a model system for antigenic variation, surviving by periodically replacing a monolayer of variant surface glycoproteins (VSG) that covers its cell surface. We compared the genome of Trypanosoma brucei with two closely related parasites Trypanosoma congolense and Trypanosoma vivax , to reveal how the variant antigen repertoire has evolved and how it might affect contemporary antigenic diversity. We reconstruct VSG diversification showing that Trypanosoma congolense uses variant antigens derived from multiple ancestral VSG lineages, whereas in Trypanosoma brucei VSG have recent origins, and ancestral gene lineages have been repeatedly co-opted to novel functions. These historical differences are reflected in fundamental differences between species in the scale and mechanism of recombination. Using phylogenetic incompatibility as a metric for genetic exchange, we show that the frequency of recombination is comparable between Trypanosoma congolense and Trypanosoma brucei but is much lower in Trypanosoma vivax . Furthermore, in showing that the C-terminal domain of Trypanosoma brucei VSG plays a crucial role in facilitating exchange, we reveal substantial species differences in the mechanism of VSG diversification. Our results demonstrate how past VSG evolution indirectly determines the ability of contemporary parasites to generate novel variant antigens through recombination and suggest that the current model for antigenic variation in Trypanosoma brucei is only one means by which these parasites maintain chronic infections.

hESCs (human embryonic stem cells) offer great potential for pharmaceutical research and development and, potentially, for therapeutic use. However, improvements in cell culture are urgently required to allow the scalable production of large numbers of cells that maintain pluripotency. Supplementing feeder-free conditions with either EHNA [erythro-9-(2-hydroxy-3-nonyl)adenine] or readily synthesized analogues of this compound maintains hESC pluripotency in the absence of exogenous cytokines. When the hESC lines SA121 or SA461 were maintained in feeder-free conditions with EHNA they displayed no reduction in stem-cell-associated markers such as Nanog, Oct4 (octamer-binding protein 4) and SSEA4 (stage-specific embryonic antigen 4) when compared with cells maintained in full feeder-free conditions that included exogenously added bFGF (basic fibroblast growth factor). Spontaneous differentiation was reversibly suppressed by the addition of EHNA, but EHNA did not limit efficient spontaneous or directed differentiation following its removal. We conclude that EHNA or related compounds offers a viable alternative to exogenous cytokine addition in maintaining hESC cultures in a pluripotent state and might be a particularly useful replacement for bFGF for large-scale or GMP (good manufacturing practice)-compliant processes.

This paper uses the child sample of Statistics Canada's 2001 Participation and Activity Limitations Survey to study the economic costs of caring for children with disabilities in Canada. Both explicit out-of-pocket expenditures and implicit costs in the form of foregone labour market opportunities are considered. Results indicate that, despite universal health insurance in Canada, a majority of families of children with disabilities incur significant economic costs. Additional financial support might be offered, particularly when the child's condition is severe, and costly therapy and specialized aids could be covered. Our results also support the need for respite as well as help in balancing work and caregiving for Canadian parents of children with disabilities.

Dans cet article, à partir des données de l’Enquête longitudinale nationale sur les enfants et les jeunes, nous tentons de répondre à trois questions. a) Élever un enfant ayant un handicap ou une maladie chronique a-t-il un effet négatif sur la santé maternelle ? b) Si oui, cet effet croît-il à long terme ? c) Cet effet est-il plus marqué chez les mères célibataires que chez celles qui sont mariées ? Nos observations nous permettent de tirer les conclusions suivantes. Les mères – mariées ou célibataires – qui élèvent un enfant ayant un handicap ou une maladie chronique affirment être en moins bonne santé. Ce phénomène s’amplifie avec le temps. Quand on tient compte des variables que sont les déterminants de la santé, on n’observe pas de différence significative entre l’état de santé des mères célibataires et celui des mères mariées, et le lien entre l’état de santé et le fait d’avoir un enfant handicapé n’est pas plus important chez les mères célibataires que chez celles qui sont mariées.

This paper analyzes how the ability to limit cooperation influences the outcome of complete information bargaining between two players. When cooperation involves prompt resolution of a conflict, as in alternating-offer games and wars-of-attrition, the solutions equate the marginal rates of substitution between earlier resolution and more private goods. When cooperation involves consent for the level of a public good, the outcome again equates the marginal rates of substitution between greater cooperation (more public good) and more private goods (lower cost shares). Here, the equilibrium consists of balanced linear cost shares given by the ratio of marginal-willingness-to-pay to marginal cost.

This paper uses panel data from the Statistics Canada National Longitudinal Survey of Children and Youth (1994–2000) to study the implications of parenting a child with a disability or chronic condition for subjective assessments of parental health. We find mother's health to be negatively affected, particularly if the disability is longer-term. Within families, the wife's health deteriorates relative to her husband's when they are parenting a child with a disability. These results are consistent with Akerlof and Kranton's [Akerlof, G., Kranton, R., 2000. Economics and identity. The Quarterly Journal of Economics 105(3), 715–753] arguments that ‘identity’ is an important determinant of both behaviour and well-being. For parents of children with disabilities, the behaviour associated with a traditional ‘good mother’ identity (e.g., care-giving) appears to have more adverse health consequences than the behaviour associated with a ‘good father’ identity (e.g., breadwinning).

This paper uses a large, nationally representative microdata survey to conduct a multivariate analysis of the correlates of self-assessed happiness for Canadian 12 to 15 year olds living in two-parent families. We ask whether the same factors matter for the happiness of young teens as for adults. And, we ask whether the correlates of being at the bottom of the young teen happiness distribution are the same as the correlates of being at the top. Results suggest that the level of family income correlates with the probability of being at the bottom of the young teen happiness distribution but not with the probability of being at the top. Relative socioeconomic position and peer social relationships, on the other hand, correlate with being at the top but not at the bottom of the young teen happiness distribution. Relationships involving significant adults (parents, teachers) are the most important correlates of young teen happiness.

Using microdata from the Luxembourg Income Study, we assess “time crunch” for families with children in Canada, Germany, Sweden, the U.K. and the U.S. Both theory and empirical evidence suggest that both time and money are important inputs to the well-being of parents and children. We present cross-country comparisons of “total available adult hours” under different assumptions about the varying time needs of families of different size. We also present estimates of “time shortages.” In all cases, we provide separate estimates for families located at different points in the country income distributions, since being short of both time and money is likely to be particularly problematic. Although paid work hours are highest for high-income families, we nonetheless find significant numbers of lower-income families in which parents work very long hours in the paid labor market; this is particularly the case in the U.S.

This paper explores the connection between the labour market and child overweight status in Canada. The labour market is a social institution which plays a critical role in determining how families live their day-to-day lives, for example, how much time and which parts of the day are available for cooking, eating and exercise. Using longitudinal data from the Statistics Canada National Longitudinal Survey of Children and Youth, we find that a history of higher hours of paid work by mothers (but not fathers) is associated with a higher probability of being 'at risk of overweight'/overweight for children aged 6-11. The policy implication we draw from this work is that additional support to better enable parents to engage in paid work without penalty to their own health or that of their children is clearly warranted.

The goal of this paper is to compare the extent of child obesity in Canada, Norway and the United States. As child poverty is an important correlate of child obesity, we wish to examine the potential role of international differences in child poverty in explaining international differences in the extent of child obesity. We use three representative microdata surveys containing parental reports of child height and weight collected in the mid-1990s in Canada, Norway and the US. We calculate both the prevalence and proportional severity of child obesity for 6-11-year-old children in each country, and represent the 'extent' of obesity diagrammatically. Differences in patterns of child poverty are similarly depicted. Obesity extent is also compared for poor and non-poor children in Canada and the US. Finally, child obesity in the three countries is compared using only non-poor children where we find that the extent of child obesity is much lower in Norway than in Canada or the US. The pattern apparent for obesity is remarkably similar to that found for child poverty. In Canada and especially in the US, we find a much greater extent of obesity for poor than non-poor children. However, when we compare only non-poor children in the three countries, although the magnitude of difference is smaller, it remains clear that Norwegian children are much less likely to be obese. Policy and research directed towards reducing the extent of child obesity in both Canada and the US should pay particular attention to issues of child poverty.

This paper explores conflicts between two groups,“the industry” and “theenvironmentalists”, over whether an indivisible resource (e.g., an ancient tree) should be harvested or preserved. In a complete information war ofattrition the environmentalists' willingness to blockade harvest attemptsmay control resource use as effectively as if they held property rights. Optimal government intervention will override this ability for somebenefit/cost combinations but may augment it for other combinations.Introducing uncertainty about the environmentalists' benefits results inextended disputes and consequent lack of efficiency. Governmentintervention for welfare reasons generally reduces these efficiencylosses.

OBJECTIVE: To estimate the prevalence of major birth defects diagnosed by 6 years of age in all births and terminations of pregnancy for fetal anomaly conceived by assisted reproductive technology (when this included intracytoplasmic sperm injection and in vitro fertilization [IVF]) and the remainder of nonassisted reproductive technology-conceived children born in Western Australia from 1994 to 2002. METHODS: This retrospective cohort study used data linkage between three population-based registers (Reproductive Technology Register, Western Australian Register of Developmental Anomalies, and Midwives' Notification of Birth System) to identify all assisted reproductive technology (n=2,911) and nonassisted reproductive technology (n=210,997) births with and without birth defects diagnosed by age 6 and all terminations of pregnancy for fetal anomaly. RESULTS: A major birth defect was diagnosed in 8.7% of assisted reproductive technology and 5.4% of nonassisted reproductive technology singletons (odds ratio [OR] 1.53, 95% confidence interval [CI] 1.30-1.79), as well as 7.1% of assisted reproductive technology twins and 5.9% of nonassisted reproductive technology twins of unlike sex (OR 1.08, 95% CI 0.77-1.51). The prevalence of birth defects in assisted reproductive technology singletons and twins decreased markedly over the study period. This change was evident across all three clinics contributing data over the whole study and was particularly marked for children conceived as a result of IVF. CONCLUSION: There has been a decrease in the prevalence of birth defects over time in children born as a result of assisted reproductive technology in Western Australia; however, the prevalence of major birth defects in assisted reproductive technology singletons remains increased compared with nonassisted reproductive technology singletons. LEVEL OF EVIDENCE: II.

We analyse the structure of the quotient $\mathrm{A}_\sim(\Gamma,X,\mu)$ of the space of measure-preserving actions of a countable discrete group by the relation of weak equivalence. This space carries a natural operation of convex combination. We show that the convex structure of $\mathrm{A}_\sim(\Gamma,X,\mu)$ is compatible with the topology, and as a consequence deduce that $\mathrm{A}_\sim(\Gamma,X,\mu)$ is path connected. Using ideas of Tucker-Drob we are able to give a complete description of the topological and convex structure of $\mathrm{A}_\sim(\Gamma,X,\mu)$ for amenable $\Gamma$ by identifying it with the simplex of invariant random subgroups. In particular we conclude that $\mathrm{A}_\sim(\Gamma,X,\mu)$ can be represented as a compact convex subset of a Banach space if and only if $\Gamma$ is amenable. We consider the space $\mathrm{A}_{\sim_s}(\Gamma,X,\mu)$ of stable weak equivalence classes and show that is always a compact convex subset of a Banach space. For a free group $\mathbb{F}_N$, we show that if one restricts to the compact convex set $\mathrm{FR}_{\sim_s}(\mathbb{F}_N,X,\mu) \subseteq \mathrm{A}_{\sim_s}(\mathbb{F}_N,X,\mu)$ of the stable weak equivalence classes of free actions, the extreme points are dense in $\mathrm{FR}_{\sim_s}(\mathbb{F}_N,X,\mu)$., Comment: 34 pages

African trypanosomes are unicellular parasites that use DNA recombination to evade the mammalian immune response. They do this in a process called antigenic variation, in which the parasites periodically switch the expression of VSG genes that encode distinct Variant Surface Glycoprotein coats. Recombination is used to move new VSG genes into specialised bloodstream VSG transcription sites. Genetic and molecular evidence has suggested that antigenic variation uses homologous recombination, but the detailed reaction pathways are not understood. In this study, we examine the recombination pathways used by trypanosomes to integrate transformed DNA into their genome, and show that they possess at least two pathways of homologous recombination. The primary mechanism is dependent upon RAD51, but a subsidiary pathway exists that is RAD51-independent. Both pathways contribute to antigenic variation. We show that the RAD51-independent pathway is capable of recombining DNA substrates with very short lengths of sequence homology and in some cases aberrant recombination reactions can be detected using such microhomologies.

The upbringing of children is modeled as a modified principal agent problem in which children attempt to maximize their own well-being when faced with a parenting strategy chosen by the parent, to maximize parent's perception of family well-being. Thus, children as well as parents are players, but children have higher discount rates than parents. The simultaneity of parenting and child behaviour is confirmed using the 1994 Canadian National Longitudinal Survey of Children.

Why do Canadian mothers have lower incomes than women who have never had children? Microdata from the 1995 GSS allow examination of two hypotheses: (1) mothers have spent more time out of the labour force, thus acquiring less human capital; (2) higher levels of unpaid work lead to fatigue and/or scheduling difficulties. Measuring work history does little to account for the ‘family gap.’ The estimated child penalty is reduced by allowing for ‘human capital depreciation’ and controlling for unpaid work hours, but the two hypotheses together cannot entirely explain the gap. JEL Classification: J0, J3 Entrees et sorties: marche du travail et consequences a long terme des interruptions dans l'experience sur le marche du travail a cause des enfants. Ce memoire se demande pourquoi les femmes canadiennes qui ont eu des enfants ont des revenus plus bas que ceux des femmes qui n'en ont pas eus. Les microdonnees de l'Enquete sociale generale de 1995 de Statistiques Canada permettent d'examiner deux hypotheses: (1) les meres ont passe plus de temps en dehors de la main d'oeuvre active et donc ont accumule moins de capital humain, ou (2) des niveaux plus eleves de travail non-remunere peuvent entrainer fatigue ou difficultes d'organisation du temps. Des efforts pour construire une meilleure image de l'experience de travail des femmes ne permettent pas d'expliquer cet ‘ecart familial,’ meme si la possibilite qu'il y ait ‘depreciation du capital humain’ reduit la penalisation attachee au fait d'avoir un enfant en particulier si l'interruption dans l'experience sur le marche du travail est suivie d'un changement d'emploi. Le nombre hebdomadaire d'heures de travail non paye est relie negativement aux revenus, et si l'on normalise pour tenir compte des heures de travail non paye cela reduit la penalisation attachee au fait d'avoir un enfant. Cependant les deux hypotheses combinees ne suffisent pas pour expliquer l'ecart.

The paper uses organisation theory to seek an explanation for the relative uniformity of governance structures (as distinct from other aspects of organisational structure) in public companies in the UK and USA. It then reviews theoretical and empirical evidence of ways in which these structures affect company performance, and finds that conventional views about the benefits of independent governance structures are not strongly supported.

This paper uses microdata from the 1992 Statistics Canada Family Expenditure Survey to provide evidence that male and female incomes do not always exert identical influences on household expenditures. The novelty of the paper lies in its demonstration that, while incomes may be pooled for some categories of consumption (e.g. housing), the income pooling hypothesis must be rejected for others. We also go beyond simply rejecting the pooling hypothesis to ask how male versus female income is used. Our results stress the on-going importance of traditional gender roles. For example, we find that expenditures on child care increase only with women’s incomes_higher male income is not associated with higher expenditure on child care even when both spouses are full-time, full-year paid workers.