Using Bayesian graphical models to model biases in observational studies and to combine multiple sources of data: application to low birth weight and water disinfection by-products

Summary.  Data in the social, behavioural and health sciences frequently come from observational studies instead of controlled experiments. In addition to random errors, observational data typically contain additional sources of uncertainty such as missing values, unmeasured confounders and selection biases. Also, the research question is often different from that which a particular source of data was designed to answer, and so not all relevant variables are measured. As a result, multiple sources of data are often necessary to identify the biases and to inform about different aspects of the research question. Bayesian graphical models provide a coherent way to connect a series of local submodels, based on different data sets, into a global unified analysis. We present a unified modelling framework that will account for multiple biases simultaneously and give more accurate parameter estimates than standard approaches. We illustrate our approach by analysing data from a study of water disinfection by-products and adverse birth outcomes in the UK.     

Intergenerational class mobility in contemporary Britain: political concerns and empirical findings

In Britain in recent years social mobility has become a topic of central political concern, primarily as a result of the effort made by New Labour to make equality of opportunity rather than equality of condition a focus of policy. Questions of the level, pattern and trend of mobility thus bear directly on the relevance of New Labour's policy analysis, and in turn are likely be crucial to the evaluation of its performance in government. However, politically motivated discussion of social mobility often reveals an inadequate grasp of both empirical and analytical issues. We provide new evidence relevant to the assessment of social mobility - in particular, intergenerational class mobility - in contemporary Britain through cross-cohort analyses based on the NCDS and BCS datasets which we can relate to earlier cross-sectional analyses based on the GHS. We find that, contrary to what seems now widely supposed, there is no evidence that absolute mobility rates are falling; but, for men, the balance of upward and downward movement is becoming less favourable. This is overwhelmingly the result of class structural change. Relative mobility rates, for both men and women, remain essentially constant, although there are possible indications of a declining propensity for long-range mobility. We conclude that under present day structural conditions there can be no return to the generally rising rates of upward mobility that characterized the middle decades of the twentieth century - unless this is achieved through changing relative rates in the direction of greater equality or, that is, of greater fluidity. But this would then produce rising rates of downward mobility to exactly the same extent - an outcome apparently unappreciated by, and unlikely to be congenial to, politicians preoccupied with winning the electoral 'middle ground'.     

How far merit selection? Social stratification and the labour market1

The question of how societies allocate occupational positions and subsequent rewards has long been of interest to sociologists. According to one influential theory, the needs of modern industrial societies and economies demand that high-level and functionally important occupational positions are allocated according to meritocratic principles. I argue that, ultimately, employers get the final say about which characteristics are rewarded in the labour market. In order to examine which skills and attributes are required by employers for particular occupations I analyse data drawn from a content analysis of c.5000 British newspaper job advertisements. The results show that both merit and non-merit characteristics are requested by employers in job advertisements, even for occupations falling within the higher classes. I also find evidence that employers have similar requirements for similar occupations, cross-cutting class boundaries.     

Advances in the surgical management of prolapse

Prolapse is an extremely common condition, for which 11% of women will have a surgical procedure at some point in their lives. The recurrence rate after most of the traditional surgical procedures is high and upto 29% of women who have had surgery for prolapse will require a further operation. In order to improve the surgical outcome, there is currently much interest in the use of grafts to augment traditional repairs and new procedures have been developed using specifically developed grafts. These have been combined with minimally invasive surgical techniques in an attempt to reduce surgical morbidity. These procedures may improve the outcome of surgery for prolapse. However, there is currently a lack of long-term data from randomized trials to demonstrate their effectiveness and safety.     

Spirit of aging rising: cross-cutting thematic modules to enrich foundation graduate social work courses

To enrich an urban generalist MSW program serving a diverse aging community, an innovative approach was initiated. A team of students, faculty and a field instructor collaborated in creating and evaluating 3 sets of cross-cutting thematic modules. An overview of the thematic modules (addressing elder abuse, family caregiving, and mental health), integrated across multiple curriculum areas (Human Behavior and the Social Environment, Macro/Policy, Practice and Research), is presented along with results of a faculty focus group evaluating the process of coordinating module content for one full week of class per foundation area (one topic per quarter).     

Roads to American Empire: U.S. Military Public Works and Capitalist Transitions, 1898–1934.

Between 1898 and 1934, in synchronous and successive U.S. military interventions and occupations in Cuba, Puerto Rico, the Philippines, Haiti, and the Dominican Republic, American soldiers made public works, and especially roads, into a global technology of imperial power. This essay examines infrastructure as a factor in state formation and capitalist transition in these five different imperial spaces as a way to study U.S. empire, and its effects on foreign societies, through a comparative, global, and intra‐imperial approach often precluded by the methodological nationalism of historical and sociological literatures. Despite significant differences between these sites of U.S. war and occupation, both prior to American interventions and during them, U.S. military public works expressed and advanced a common political‐economic logic of state centralization and capital accumulation. Colonial and post‐colonial political institutions and political economies, the strength of central governments, the extent of plantation agriculture and rural proletarianization, world commodity markets, and geography and natural events varied, but determined U.S. imperial infrastructure's outcomes. By the 1930s, the U.S. military had elevated infrastructural improvement to a key repertoire of American imperial power in the world, and one which persisted as the United States turned away from formal colonialism in the era of the Cold War and decolonization.     

Sociological Factors Affecting Agricultural Price Risk Management in Australia*

Abstract The highly volatile auction system in Australia accounts for 85 percent of ex‐farm wool sales, with the remainder sold by forward contract, futures, and other hedging methods. In this article, against the background of an extensive literature on price risk strategies, we investigate title behavioral factors associated with producers' adoption of price risk‐management strategies (specifically futures and forward contracts) for selling wool. This research presents a behavioral model based on Diffusion of Innovations, the Theory of Reasoned Action, and the Theory of Planned Behavior. We found that the auction system is used as a price risk‐management tool because other selling methods are considered more risky. We also report on a curious relationship between risk and complexity in terms of wool producers' intentions to use forward contracts. We explored sociological factors in conjunction with focus‐group data in an attempt to understand this relationship. This exercise yielded some interesting findings on the impact that trust, habit, social cohesion, and networks have on decision making in the rural community. The significance of this article lies in its application of core sociological theory in a new research context: the Australian wool industry.     

Changing land tenure patterns in Scotland: A time for reform?

Land tenure patterns throughout Britain have changed significantly. The popularity of the traditional agricultural tenancy has declined and in response to legislative and policy developments landowners have become reluctant to enter into long-term tenancy arangements with tenants. The result has been a growth in a number of short term leases. In response, legislative reform took place in England and Wales during 1995 and introduced a farm business tenancy. It provides for greater freedom to negotiate individual agreements. However, Scotland has been excluded. This paper illustrates that Scotland has experienced similar changes to those observed elsewhere and that the main short term lease (limited partnership tenancy) currently popular with Scottish landowners is fraught with legal and administrative difficulties. The limited partnership tenancy is not a suitable alternative to the traditional agricultural tenancy and as such there may be a case for the extension of the farm business tenancy to Scotland.