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Abstract Purpose--The purpose of this paper is to outline a method for evaluating gearing ratios when the loan rate and the rate of growth of the asset value are subject [...]

Scenario analysis has emerged as a key tool to analyze complex and uncertain future socio-ecological developments. However, currently existing global scenarios (narratives of how the world may develop) have neglected biological invasions, a major threat to biodiversity and the economy. Here, we use a novel participatory process to develop a diverse set of global biological invasion scenarios spanning a wide range of plausible global futures through to 2050. We adapted the widely used “two axes” scenario analysis approach to develop four families of four scenarios each, resulting in 16 scenarios that were later clustered into four contrasting sets of futures. Our analysis highlights that socioeconomic developments and technological innovation have the potential to shape biological invasions, in addition to well-known drivers, such as climate and human land use change and global trade. Our scenarios partially align with the shared socioeconomic pathways created by the climate change research community. Several factors that drive differences in biological invasions were underrepresented in the shared socioeconomic pathways; in particular, the implementation of biosecurity policies. We argue that including factors related to public environmental awareness and technological and trade development in global scenarios and models is essential to adequately consider biological invasions in global environmental assessments and thereby obtain a more integrative picture of future social–ecological developments.

How might analytic reasoning in intelligence reports be substantially improved? One conjecture is that this can be achieved through a combination of crowdsourcing and structured analytic techniques (SATs). To explore this conjecture, we developed a new crowdsourcing platform supporting groups in collaborative reasoning and intelligence report drafting using a novel SAT we call “Contending Analyses.” In this paper we present findings from a large study designed to assess whether groups of professional analysts working on the platform produce better-reasoned reports than those analysts produce when using methods and tools normally used in their organizations. Secondary questions were whether professional analysts working on the platform produce better reasoning than the general public working on the platform; and how usable the platform is. Our main finding is a large effect size (Cohen’s d= 1.37) in favor of working on platform. This provides early support for the general conjecture. We discuss limitations of our study, implications for intelligence organizations, and future directions for the work as a whole.

Sustainable green chemistry depends on technically feasible, cost-effective and socially acceptable decisions by regulators, industry and the wider community. The discipline needs to embrace a new suite of tools and train proponents in their use. We propose a set of tools that will bridge the gap between technical feasibility and efficiency on one hand, and social preferences and values on the other. We argue that they are indispensable in the next generation of regulators and chemistry industry proponents.

Abstract: Surveys that record the presence or absence of fauna are used widely in wildlife management and research. A false absence occurs when an observer fails to record a resident species. There is a growing appreciation of the importance of false absences in wildlife surveys and its influence on impact assessment, monitoring, habitat analyses, and population modeling. Very few studies explicitly quantify the rate of these errors. Quantifying the rate of false absences provides a basis for estimating the survey effort necessary to assert that a species is absent with a pre-specified degree of confidence and allows uncertainty arising from false absences to be incorporated in inference. We estimated the rate of false absences for 2 species of forest owl and 4 species of arboreal marsupial based on 8 repeat visits to 50 survey locations in south-eastern Australia. We obtained estimates using a generalized zero-inflated binomial model. We presented detectability curves for each species to convey the number of visits required to achieve a specified level of confidence that resident species will be detected. The observation error rates we calculated were substantial but varied between species. For the least detectable species, the powerful owl (Ninox strenua), our standard surveys returned false absences on 87% of visits. However, our surveys of the more detectable sugar glider (Petaurus breviceps) returned a 45% false absence rate. We predict that approximately 18 visits would be required to be 90% sure of detecting resident owls and approximately 5 visits would provide 90% confidence of detecting resident sugar gliders. We fitted hierarchical logistic regression models to the data to describe the variation in detection rates explained by environmental variables. We found that temperature, rainfall, and habitat quality influenced the detectability of most species. Consideration of observation error rates could result in important changes to resource management and conservation planning.

SummaryThe primary roles for population viability analysis (PVA) in bird conservation are to predict the consequences of human actions for populations, and to assist in the design of research and monitoring programs. PVAs have limitations that compromise their ability to predict the future accurately. But all predictions are error prone. The lack of completely reliable and verifiable predictions does not detract from the utility of PVAs because their primary output is to reinforce the rigour and transparency of environmental decision making. The imperative for PVAs is driven by the weaknesses of alternative approaches that rest on undefined and unrepeatable subjective processes. Subjective estimation is known to be biased and inaccurate and this review contends that many alternatives to PVA will produce worse results.

The spatial structure, age structure and population dynamics of the shrub Kunzea ericoides(A. Rich.) J. Thompson were investigated at Coranderrk Reserve, near Healesville, Victoria, Australia. The shrub is known to be invasive in many areas and, although indigenous to the reserve, has greatly increased its population size and distribution within the reserve in the past 30 years. Dendrochronology showed a constant relationship between age and stem diameter for K. ericoidesin the reserve. The spatial structure of the variable stem diameter was investigated by the use of spatial correlograms and results suggested that K. ericoidesis spreading via the formation of discrete clumps and gap-phase regeneration. The two main populations in the reserve recruited continuously in time but patchily in space. A simple statistical model for size–frequency data showed that K. ericoidesis expanding faster in some areas of the reserve than others. The trend of expansion of K. ericoidesmay be irreversible. Intensive management of Coranderrk Reserve will be required if K. ericoidesis to be controlled and the conservation value of the reserve maintained.

A total of 141 vascular plant species were recorded from 20 quadrats on five isolated granite outcrops in southern Western Australia. The distributions of common plants, rare plants, trophic guids, and the complete data were analysed with respect to substrate (on sheet granite or scree), location (on granite outcrops), and a broader classification of locations into two western and three eastern outcrops. Most of the observed correlations were in accord with an hypothesis of environmental control that predicts distributions reflecting spatially autocorrelated environmental parameters. However, plant guilds were very strongly correlated with substrate and relatively weakly correlated with location, a result that can be explained by coexistence through geographic replacement and contingent exclusion. Rare plants were more likely to grow on either substrate than were common plants, which contrasts with the supposition that rare plants have limited environmental tolerances, but may have been caused by spatial or temporal mass effects. The Mantel test and its recent extensions allow non-exclusive, competing hypotheses to be distinguished.

A comparative study of the accuracy of three different approaches to phylogenetic estimation was made on simulated data with differing rates of change in different lineages. The three approaches were maximum likelihood, maximum parsimony, and phenetic clustering. The data were generated by simulating genetic drift with different population sizes over a simple four‐species tree topology. Although the accuracy of all three approaches was found to be dependent on the number of loci (characters), maximum likelihood was found to perform considerably and consistently better than maximum parsimony or phenetic clustering.

In this article the author reflects on the issue whether experts can be trusted. It is suggested that expert opinions are needed because the time, resources and data to assess the risks are unavailable. According to the author, the problem associated with such a system lies in the tendency of experts to assume a position of authority, reinforced by professional membership. Structured procedures to elicit judgments are cited as a means to lessen some of the pervasive psychological biases.