The politics of ‘platforms’ Gillespie, Tarleton
New media & society,
05/2010, Letnik:
12, Številka:
3
Journal Article
Recenzirano
Online content providers such as YouTube are carefully positioning themselves to users, clients, advertisers and policymakers, making strategic claims for what they do and do not do, and how their ...place in the information landscape should be understood. One term in particular, ‘platform’, reveals the contours of this discursive work. The term has been deployed in both their populist appeals and their marketing pitches, sometimes as technical ‘platforms’, sometimes as ‘platforms’ from which to speak, sometimes as ‘platforms’ of opportunity. Whatever tensions exist in serving all of these constituencies are carefully elided. The term also fits their efforts to shape information policy, where they seek protection for facilitating user expression, yet also seek limited liability for what those users say. As these providers become the curators of public discourse, we must examine the roles they aim to play, and the terms by which they hope to be judged.
There is considerable concern over declines in insect pollinator communities and potential impacts on the pollination of crops and wildflowers. Among the multiple pressures facing pollinators, ...decreasing floral resources due to habitat loss and degradation has been suggested as a key contributing factor. However, a lack of quantitative data has hampered testing for historical changes in floral resources. Here we show that overall floral rewards can be estimated at a national scale by combining vegetation surveys and direct nectar measurements. We find evidence for substantial losses in nectar resources in England and Wales between the 1930s and 1970s; however, total nectar provision in Great Britain as a whole had stabilized by 1978, and increased from 1998 to 2007. These findings concur with trends in pollinator diversity, which declined in the mid-twentieth century but stabilized more recently. The diversity of nectar sources declined from 1978 to 1990 and thereafter in some habitats, with four plant species accounting for over 50% of national nectar provision in 2007. Calcareous grassland, broadleaved woodland and neutral grassland are the habitats that produce the greatest amount of nectar per unit area from the most diverse sources, whereas arable land is the poorest with respect to amount of nectar per unit area and diversity of nectar sources. Although agri-environment schemes add resources to arable landscapes, their national contribution is low. Owing to their large area, improved grasslands could add substantially to national nectar provision if they were managed to increase floral resource provision. This national-scale assessment of floral resource provision affords new insights into the links between plant and pollinator declines, and offers considerable opportunities for conservation.
Public debate about content moderation has overwhelmingly focused on removal: social media platforms deleting content and suspending users, or opting not to do so. However, removal is not the only ...available remedy. Reducing the visibility of problematic content is becoming a commonplace element of platform governance. Platforms use machine learning classifiers to identify content they judge misleading enough, risky enough, or offensive enough that, while it does not warrant removal according to the site guidelines, warrants demoting them in algorithmic rankings and recommendations. In this essay, I document this shift and explain how reduction works. I then raise questions about what it means to use recommendation as a means of content moderation.
AI seems like the perfect response to the growing challenges of content moderation on social media platforms: the immense scale of the data, the relentlessness of the violations, and the need for ...human judgments without wanting humans to have to make them. The push toward automated content moderation is often justified as a necessary response to the scale: the enormity of social media platforms like Facebook and YouTube stands as the reason why AI approaches are desirable, even inevitable. But even if we could effectively automate content moderation, it is not clear that we should.
Objectives To present the updated results of systematic review of the current evidence for the effectiveness of hip protectors from reports of completed randomised trials, and to explore the ...evolution of that evidence. Design Systematic review with meta-analysis. Data sources Cochrane Bone, Joint, and Muscle Trauma Group trials register (January 2005), Cochrane central register of controlled trials (Cochrane Library Issue 1, 2005), Medline (1966 to January 2005), Embase (1988 to January 2005), and CINAHL (1982 to December 2004). Other databases and reference lists of relevant articles were searched and some trialists were contacted. Review methods Randomised or quasirandomised controlled trials reporting the incidence of hip fractures, pelvic fractures, and other fractures in elderly people offered hip protectors compared with a control group that was not. Results Outcomes for fracture were available from 14 randomised and quasirandomised trials. Pooling of data from 11 trials carried out in nursing or residential care settings, including six cluster randomised studies, showed evidence of a marginally statistically significant reduction in incidence of hip fracture (relative risk 0.77, 95% confidence interval 0.62 to 0.97). Pooling of data from three individually randomised trials of 5135 community dwelling participants showed no reduction in hip fracture incidence with provision of hip protectors (1.16, 0.85 to 1.59). No evidence was found of any significant effect of hip protectors on incidence of pelvic or other fractures. No important adverse effects of hip protectors were reported, but compliance, particularly in the long term, was poor. Conclusions On the basis of early reports of randomised trials, hip protectors were advocated. Accumulating evidence indicates that hip protectors are an ineffective intervention for those living at home and that their effectiveness in an institutional setting is uncertain.
This article draws on original empirical research in Accra, Ghana to explore the particular dynamics that contemporary processes of class-based dispossession assume at the urban scale, posing the ...concept of 'accumulation by urban dispossession'. It responds to recent calls to shift the focus of urban theory from North to South and demonstrates how widely used concepts must be interrogated and reworked as they travel from place to place. Accra is home to a large informal proletariat that is excluded from formal wage labour and housing markets and therefore has to create urban commons in order to reproduce itself. Since these commons place limits to capital's ability to valorise the urban fabric, state-led accumulation by urban dispossession is a strategic response that employs a range of physical-legal and discursive mechanisms to overcome these limits through the enclosure of the urban commons and the expulsion of the informal poor. This argument problematises Harvey's capital-centric theory of accumulation by dispossession, which treats enclosure as a fix for capital's inherent crisis tendencies. Furthermore, it demonstrates that primitive accumulation in this context differs from the classic form described by Marx on the grounds that it is based on the expulsion of the dispossessed rather than their incorporation into the capital relation as labour power.
The Real Estate Frontier Gillespie, Tom
International journal of urban and regional research,
July 2020, 2020-07-00, 20200701, Letnik:
44, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Africa's major cities are experiencing dramatic transformation as a result of growing real estate investment. This article explores whether existing theories can explain the dynamics of urban ...redevelopment in an African context, and how African cases can inform new theorizations of real estate driven urban transformation. Examining the utility of theories of gentrification and speculative urbanism for understanding urban redevelopment in Accra, Ghana, it argues that urban redevelopment in this city has been shaped by its particular (post)colonial history of state land acquisition and urban planning. Rather than simply identifying empirical variation on established theories, however, the article draws on recent research on commodity frontiers to propose an original theorization of urban redevelopment in Accra in terms of the production of a ‘real estate frontier’. This real estate frontier is characterized by the incremental and contested commodification of state land to enable the growth of the real estate sector in the city. The article concludes by calling for a comparative research agenda to better understand real estate frontiers globally.
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