STOCHASTIC WEALTH DYNAMICS AND RISK MANAGEMENT AMONG A POOR POPULATION

The literature on economic growth and development has focused considerable attention on questions of risk management and the possibility of multiple equilibria associated with poverty traps. We use herd history data collected among pastoralists in southern Ethiopia to study stochastic wealth dynamics among a very poor population. These data yield several novel findings. Although covariate rainfall shocks plainly matter, household-specific factors, including own herd size, account for most observed variability in wealth dynamics. Despite longstanding conventional wisdom about common property grazing lands, we find no statistical support for the tragedy of the commons hypothesis. It appears that past studies may have conflated costly self-insurance with stocking rate externalities. Such self-insurance is important in this setting because weak livestock markets and meager social insurance cause wealth to fluctuate largely in response to biophysical shocks. These shocks move households between multiple dynamic wealth equilibria toward which households converge following nonconvex path dynamics. The lowest equilibrium is consistent with the notion of a poverty trap. These findings have broad implications for the design of development and relief strategies among a poor population extraordinarily vulnerable to climatic shocks.common property, covariate risk, Ethiopia, idiosyncratic risk, poverty traps, social insurance, Risk and Uncertainty, O1, Q12,

Generalizability of heterogeneous treatment effect estimates across samples

The extent to which survey experiments conducted with nonrepresentative convenience samples are generalizable to target populations depends critically on the degree of treatment effect heterogeneity. Recent inquiries have found a strong correspondence between sample average treatment effects estimated in nationally representative experiments and in replication studies conducted with convenience samples. We consider here two possible explanations: low levels of effect heterogeneity or high levels of effect heterogeneity that are unrelated to selection into the convenience sample. We analyze subgroup conditional average treatment effects using 27 original–replication study pairs (encompassing 101,745 individual survey responses) to assess the extent to which subgroup effect estimates generalize. While there are exceptions, the overwhelming pattern that emerges is one of treatment effect homogeneity, providing a partial explanation for strong correspondence across both unconditional and conditional average treatment effect estimates

Key Issues Generated from the XI International Rangeland Congress 2021: Summary and Way Forward

The important issues, knowledge gaps, and evolving research approaches for the global rangelands are summarised in this review of submissions to the Joint XXIV International Grasslands and XI International Rangelands Congress (IGC/IRC). In the big picture, it is concluded that stand-alone studies of livestock production are becoming rare compared to that of the past International Rangelands Congresses (IRC). Rather, added effort is now being directed at understanding the fuller context of social-ecological systems (SESs) on rangelands in a quest to improve the prospects for sustainable resource management as well as the enhancement of human welfare. Although climate change is upon us, there was still a dearth of papers that dealt with broad- scaled climate-adaptation per se; opportunities to improve local drought response were the default topics here with a focus on implementing better drought early warning systems and integrating perspectives among producers and scientists. Invasive species challenges remain as prominent global concerns, and woody encroachment is viewed as a major contributor to rangeland degradation. Treatments to combat rangeland degradation can involve innovative layering methods incorporating grazing management and use of prescribed fire. While there is an important backdrop concerning ecosystem services from rangelands, research in this area is still in its infancy. Analysing trade-offs between production and conservation for services such as carbon sequestration loom large going forward. There were relatively few papers concerning wildlife, tourism, and associated issues; successes and challenges for natural resource conservancies were noted, in particular. These are topics that merit more creative research and development attention in the future. Some contributions highlighted the important issue of landscape conversion from rangelands to cultivation; in conjunction with human population growth, loss of such key resources can be very negative for wildlife and associated values. In terms of pastoralism and related sub-themes, while it was noted that the majority of studies now embrace SESs and integrated, participatory, action- oriented approaches, there is little effort to standardize methodologies. A focus on repeatable methods can help grow sustainability science on rangelands, and this is a challenge for research and outreach education. The volume of studies submitted overall indicated a decided numerical advantage for the Global South over the Global North. Why this is the case remains unclear, however. Disciplinary research traditions in wealthier nations may not yet provide the incentives needed to spur innovative SES work. Finally, policy makers are seen by many investigators as being ignorant of rangeland development issues. It is argued, however, that this view has not changed for 40 years. How to better engage policy makers in comprehensive SES projects is an important future goal. Policy makers themselves can then also become human research subjects in the overall process. Based on our review the future for IRC stakeholders is clear: Continue the expansion of interdisciplinary SES and action-based approaches and increase attention to climate-change adaptation/mitigation, ecosystem services, community-based development, human empowerment, market development, poverty mitigation, and creation of effective policy frameworks

Audio Barlow twins: self-supervised audio representation learning

The Barlow Twins self-supervised learning objective requires neither negative samples or asymmetric learning updates, achieving results on a par with the current state-of-the-art within Computer Vision. As such, we present Audio Barlow Twins, a novel self-supervised audio representation learning approach, adapting Barlow Twins to the audio domain. We pre-train on the large-scale audio dataset AudioSet, and evaluate the quality of the learnt representations on 18 tasks from the HEAR 2021 Challenge, achieving results which outperform, or otherwise are on a par with, the current state-of-the-art for instance discrimination self-supervised learning approaches to audio representation learning. Code at https://github.com/jonahanton/SSL_audio

How Do UX Practitioners Communicate AI as a Design Material? Artifacts, Conceptions, and Propositions

UX practitioners (UXPs) face novel challenges when working with and communicating artificial intelligence (AI) as a design material. We explore how UXPs communicate AI concepts when given hands-on experience training and experimenting with AI models. To do so, we conducted a task-based design study with 27 UXPs in which they prototyped and created a design presentation for a AI-enabled interface while having access to a simple AI model training tool. Through analyzing UXPs' design presentations and post-activity interviews, we found that although UXPs struggled to clearly communicate some AI concepts, tinkering with AI broadened common ground when communicating with technical stakeholders. UXPs also identified key risks and benefits of AI in their designs, and proposed concrete next steps for both UX and AI work. We conclude with a sensitizing concept and recommendations for design and AI tools to enhance multi-stakeholder communication and collaboration when crafting human-centered AI experiences

A Draft Regional Guidebook for Applying the Hydrogeomorphic Approach to Wet Hardwood Flats on Mineral Soils in the Coastal Plain of Virginia

The hydrogeomorphic (HGM) approach applies functional indices to the assessment of functions by comparing functions across a suite of reference sites that range from severely altered to unaltered. This Draft Regional Guidebook is the result of applying the HGM approach to Hardwood Mineral Flats in the coastal plain of Virginia. In developing the Draft Regional Guidebook, various models from Kentucky, Pennsylvania, and North Carolina, as well as, input from a workshop held in Wakefield, Virginia on May 13-14, 1998 were used to provide a template for model development. The workshop was attended by hydrologists, biogeochemists, soil scientists, wildlife biologists, and botanists from the public, private and academic sectors who have extensive knowledge of Hardwood Mineral Flats (Table 1 ). This Draft Regional Guidebook incorporates material from the Regional Guidebook for Applying the Hydrogeomorphic Approach to Wet Pine Flats on Mineral Soils in the Atlantic and Gulf Coastal Plains by Richard Rheinhardt, Martha Rheinhardt, and Mark Brinson (1999). Excerpted material includes the overview of the HGM approach and the hydrology section (since the approach utilized for pine flats is also appropriate for hardwood flats). Additional input was gained from the Draft Functional Assessment for Deciduous Mineral Flat Wetlands, Version 5 - 1999 by the Natural Resources Conservation Service staff. Valuable suggestions from end-users of other HGM guidebooks regarding the pros and cons of various sampling methods were considered and incorporated into this draft guidebook where possible. An attempt was made to incorporate data that is routinely collected as part of wetlands delineations to reduce duplication of field data and expedite the assessment procedure. The field sampling time for this assessment will depend on the size of the site, and the skill level and number of personnel. The sampling assessment protocol can be conducted by one person (though sampling of microtopography will require the use of a measured stake that can be installed temporarily in the ground). Two people can collect field data on a three- plot site in three to four hours

Significance of fish–sponge interactions in coral reef ecosystems

Sponges (Porifera) are a key component of many coral reef ecosystems. In some biogeographic regions, they are considered the dominant benthic fauna and they have the capacity to fulfil many similar roles to reef-building scleractinians. Certainly, sponges predominate at depth, below the critical thresholds of most coral species. The biological and physical attributes of these biogenic communities contribute essential resources for many reef-associated fishes. However, while fish–sponge interactions have been widely documented, there is no global synthesis of the literature on these interrelationships from the perspective of fish ecology. Here we evaluate coral reef fish–sponge relationships, including the role of sponges in providing food and shelter for fishes, the influence fishes have on sponge distribution and abundance and possible outcomes of climate change on fish–sponge interactions. To date, 16 fish families have been shown to associate with 56 different sponge genera, using them as either a source of shelter (n = 17) or a food source (n = 50), although methodologies for the latter currently lack consistency. We demonstrate that a more comprehensive understanding of fish–sponge interactions has been garnered from tropical Atlantic coral reefs, which has resulted in a strong biogeographic bias. While it is evident that in some areas of the Caribbean fish are key in shaping the distribution and abundance of sponges, it is not yet known whether this conclusion applies to the Indo-Pacific. With increasing stresses such as bleaching events impacting coral reef ecosystems, further work is needed to evaluate whether sponges can fulfil similar functional roles to those previously provided by reef-building scleractinians. Similarly, determining whether sponge expansion will compensate for the negative effects of reef degradation, or contribute to their decline, is vital