Predicting the Risk of Biological Invasions Using Environmental Similarity and Transport Network Connectedness

Understanding the risk of biological invasions associated with particular transport pathways and source regions is critical for implementing effective biosecurity management. This may require both a model for physical connectedness between regions, and a measure of environmental similarity, so as to quantify the potential for a species to be transported from a given region and to survive at a destination region. We present an analysis of integrated biosecurity risk into Australia, based on flights and shipping data from each global geopolitical region, and an adaptation of the “range bagging” method to determine environmental matching between regions. Here, we describe global patterns of environmental matching and highlight those regions with many physical connections. We classify patterns of global invasion risk (high to low) into Australian states and territories. We validate our analysis by comparison with global presence data for 844 phytophagous insect pest species, and produce a list of high‐risk species not previously known to be present in Australia. We determined that, of the insect pest species used for validation, the species most likely to be present in Australia were those also present in geopolitical regions with high transport connectivity to Australia, and those regions that were geographically close, and had similar environments.     

A Risk-Based Method for Modeling Traffic Fatalities

We describe a risk-based analytical framework for estimating traffic fatalities that combines the probability of a crash and the probability of fatality in the event of a crash. As an illustrative application, we use the methodology to explore the role of vehicle mix and vehicle prevalence on long-run fatality trends for a range of transportation growth scenarios that may be relevant to developing societies. We assume crash rates between different road users are proportional to their roadway use and estimate case fatality ratios (CFRs) for the different vehicle-vehicle and vehicle-pedestrian combinations. We find that in the absence of road safety interventions, the historical trend of initially rising and then falling fatalities observed in industrialized nations occurred only if motorization was through car ownership. In all other cases studied (scenarios dominated by scooter use, bus use, and mixed use), traffic fatalities rose monotonically. Fatalities per vehicle had a falling trend similar to that observed in historical data from industrialized nations. Regional adaptations of the model validated with local data can be used to evaluate the impacts of transportation planning and safety interventions, such as helmets, seat belts, and enforcement of traffic laws, on traffic fatalities.     

BURR CRITICAL VALUE APPROXIMATIONS FOR TESTS OF AUTOCORRELATION AND HETEROSCEDASTICITY

The paper evaluates the accuracy of Burr approximations of critical values and p-values for test a of autocorrelation and heteroscedasticity in the linear regression model.     

FINITE HORIZONS, INFINITE HORIZONS, and THE REAL INTEREST RATE

Using an overlapping-generations model in which households may have either finite or infinite horizons, I derive the implications of each horizon for the steady-state real interest rate. I then formulate an econometric model of the steady-state real interest rate and devise tests that can distinguish between finite and infinite horizons. These tests are applied to annual and quarterly U.S. data, which span the period 1875–1988. The results are inconsistent with finite horizons, and broadly consistent with infinite horizons.     

The organizational shaping of collective identity: The case of lesbian and gay film festivals in New York

Using information gathered during fieldwork on New York lesbian and gay film festival organizations, this paper argues that scholarship on identity has not paid sufficient attention to the organizational mediation of collective identity. The shape of collective identity—how internal instabilities and diversities are accommodated, in this case—depends not only on the emergent characteristics of the “collective,” but also on the resolution of challenges particular to organizational fields. Two very differently conceived lesbian and gay festival organizations, sites at which decision making about collective identity is ongoing and self-conscious, are examined. The analysis traces how each responds to two related tasks: maintaining community legitimacy, which requires racial diversification, and surviving within an altered institutional environment. Rather than imposition from “above” or construction from “below,” the adaptive responses by organizations (to changes in both community expectations and the resource environment) transform the collective identity formulations reaching public visibility. Earlier versions of this paper were presented at the Colloquium Series of the Center for Lesbian and Gay Studies, City University of New York, 1995, and at the Annual Meeting of the American Sociological Association, Washington, DC, 1995.     

The Sociology of Expertise: The Distribution of Social Fluency

Expert knowledge is an essential component of modern society. It is also a potentially difficult topic for sociology because of the importance sociology attaches to culture and context. The sociology of science has emphasised the continuity between scientific expertise and more traditional forms of knowledge. Whilst this suggests an increasing 'democratisation of expertise' is desirable, it also risks erasing the idea of expertise itself. This might be particularly detrimental for sociology as it restricts the role of sociological inquiry to examining how expert status is attributed rather than understanding what expertise is. This paper describes these developments and contrasts them with other approaches in which expertise appears less important. It concludes by setting out a new approach to expertise that respects the role of culture in generating knowledge but, by stressing the importance of socialisation and experience, argues for a more nuanced conception of expertise as both real and unequally distributed.     

Stochastic Modelling of Times to Temperature for Furnaces Supplying Titanium Blooms to a Rolling Mill at TIMET

In conjunction with TIMET at Waunarlwydd (Swansea, UK) a model has been developed that will optimise the scheduling of various blooms to their eight furnaces so as to minimise the time taken to roll these blooms into the finished mill products. This production scheduling model requires reliable data on times taken for the various furnaces that heat the slabs and blooms to reach the temperatures required for rolling. These times to temperature are stochastic in nature and this paper identifies the distributional form for these times using the generalised F distribution as a modelling framework. The times to temperature were found to be similarly distributed over all furnaces. The identified distributional forms were incorporated into the scheduling model to optimise a particular campaign that was run at TIMET Swansea. Amongst other conclusion it was found that, compared to the actual campaign, the model produced a schedule that reduced the makespan by some 35%.     

Scissors, Surveys, And Psycho-Prophylactics: Prenatal Health Care Campaigns And State Building In China, 1949–1954

This paper examines how the Chinese state's prenatal health care campaigns of the early 1950s attempted to redefine women's social and political roles. The replacement of local midwifing practices with a uniform birthing method in order to radically reduce infant and mother mortality entailed complex ramifications regarding the relationship of women vis-a-vis the state. Campaigns involved demonizing "traditional" midwifing, promoting a statistical vision of female reproductivity and children as national resources, and the isolation of individual mothers as directly responsible to the state for managing reproduction for the national interest. In sum, a physiological definition of gender was used to open women's bodies to state management. Utopic visions of painless childbirth and of the socialist nation as a giant new family were used to promote participation in grassroots campaigns, but the sources also point to forms of local resistance to the micro-level reorganization of power these campaigns intended.