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Architectures of Virtual Decision-Making: The Emergence of Gender Discrimination on a Crowdfunding Website [article]

Jason Radford
2014 arXiv   pre-print
and Decision-Making Existing research has demonstrated that providing individuals with gendered information changes the way they process information, make choices, and behave; most often in ways that 2 Radford  ... 
arXiv:1406.7550v1 fatcat:e6damqb5ebb2djvstzmluzsrte

Volunteer Science

Jason Radford, Andy Pilny, Ashley Reichelmann, Brian Keegan, Brooke Foucault Welles, Jefferson Hoye, Katherine Ognyanova, Waleed Meleis, David Lazer
2016 Social psychology quarterly  
BIOS Jason Radford is a graduate student in sociology at the University of Chicago and the project lead for Volunteer Science.  ...  In fact, all experiment code, data, and analytic code for this study is posted on Dataverse (Radford et al. 2016 ).  ... 
doi:10.1177/0190272516675866 fatcat:zxzgnllxsveufoj22ppjyn55na

Meaningful measures of human society in the twenty-first century

David Lazer, Eszter Hargittai, Deen Freelon, Sandra Gonzalez-Bailon, Kevin Munger, Katherine Ognyanova, Jason Radford
2021 Nature  
Science rarely proceeds beyond what scientists can observe and measure, and sometimes what can be observed proceeds far ahead of scientific understanding. The twenty-first century offers such a moment in the study of human societies. A vastly larger share of behaviours is observed today than would have been imaginable at the close of the twentieth century. Our interpersonal communication, our movements and many of our everyday actions, are all potentially accessible for scientific research;
more » ... times through purposive instrumentation for scientific objectives (for example, satellite imagery), but far more often these objectives are, literally, an afterthought (for example, Twitter data streams). Here we evaluate the potential of this massive instrumentation-the creation of techniques for the structured representation and quantification-of human behaviour through the lens of scientific measurement and its principles. In particular, we focus on the question of how we extract scientific meaning from data that often were not created for such purposes. These data present conceptual, computational and ethical challenges that require a rejuvenation of our scientific theories to keep up with the rapidly changing social realities and our capacities to capture them. We require, in other words, new approaches to manage, use and analyse data.
doi:10.1038/s41586-021-03660-7 pmid:34194043 fatcat:quvg4byw2fg3jggfplazs4tpjy

Theory In, Theory Out: The Uses of Social Theory in Machine Learning for Social Science

Jason Radford, Kenneth Joseph
2020 Frontiers in Big Data  
At the same time, many (computational) social scientists have noted fundamental problems with a range of research that uses machine learning on social data (Lazer and Radford, 2017; Crawford et al., 2019  ...  Copyright © 2020 Radford and Joseph. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).  ... 
doi:10.3389/fdata.2020.00018 pmid:33693392 pmcid:PMC7931881 fatcat:vjl4sp43jfchhpch32qkduz4by

A Distinctive New Species Of Cloud Forest Euptychiina (Lepidoptera: Nymphalidae: Satyrinae) From Ecuador And Peru

Keith Willmott, Gerardo Lamas, James Radford, Mario Marín, Shinichi Nakahara, Marianne Espeland, Lei Xiao, Jason Hall
2018 Zenodo  
specimens of the new species described here were collected during targeted surveys of the Cordillera del Cóndor in Ecuador by the Cambridge University Lepidoptera Expedition to the 'Tercera Cordillera' (see Radford  ...  tree was extracted from a much larger dataset for Euptychiina (Espeland et al., unpubl. data) . : HOLOTYPE ♂: ECUADOR: Zamora-Chinchipe: Destacamento Paquisha Alto, [3°54'5''S,78°28'59''W], 2324 m, (Radford  ... 
doi:10.5281/zenodo.1309676 fatcat:ljv73no7vre3dhc4wsry6mb2oa

The Cornell Caltech Atacama Telescope status and technical progress

Thomas A. Sebring, Simon Radford, Riccardo Giovanelli, Jason Glenn, David Woody, Larry M. Stepp, Roberto Gilmozzi
2008 Ground-based and Airborne Telescopes II  
shows a waveguide in the test configuration. [8] Fig 4 . 4 Radii of the dome and of the volumes swept by the primary mirror and the secondary mirror support for different primary focal ratios (Simon Radford  ... 
doi:10.1117/12.787586 fatcat:mmzginndlzaivbxdv53rrp545y

The Safety of Warfarin Therapy in the Nursing Home Setting

Jerry H. Gurwitz, Terry S. Field, Martha J. Radford, Leslie R. Harrold, Richard Becker, George Reed, Kristin DeBellis, Jason Moldoff, Nancy Verzier
2007 American Journal of Medicine  
PURPOSE: We examined the preventability of adverse warfarin-related events and potential adverse warfarin-related events ("near misses") in the nursing home setting. METHODS: We performed a cohort study of all long-term care residents of 25 nursing homes (bed size range, 90-360) in Connecticut during a 12-month observation period. The total number of residents in these facilities ranged from 2946 to 3212 per quarter. There were 490 residents who received warfarin therapy. Possible
more » ... ed incidents were detected by quarterly retrospective review of nursing home records by trained nurse abstractors. Each incident was independently classified by 2 physician-reviewers to determine whether it constituted a warfarin-related event, its severity, and its preventability. The primary outcome was an adverse warfarin-related event, defined as an injury associated with the use of warfarin. Potential adverse warfarin-related events were defined as situations in which the international normalized ratio (INR) was noted to be 4.5 or greater, an error in management was noted, but no injury occurred. We also assessed time in specified INR ranges per nursing home resident day on warfarin. RESULTS: Over the 12-month observation period, 720 adverse warfarin-related events and 253 potential adverse warfarin-related events were identified. Of the adverse warfarin-related events, 625 (87%) were characterized as minor, 82 (11%) were deemed serious, and 13 (2%) were life-threatening or fatal. Overall, 29% of the adverse warfarin-related events were judged to be preventable. Serious, life-threatening, or fatal events occurred at a rate of 2.49 per 100 resident-months; 57% of these more severe events were considered preventable. Errors resulting in preventable events occurred most often at the prescribing and monitoring stages of warfarin management. The percentages of time in the less than 2, 2 to 3, and more than 3 INR ranges were 36.5%, 49.6%, and 13.9%, respectively. CONCLUSIONS: The use of warfarin in the nursing home setting presents substantial safety concerns for patients. Adverse events associated with warfarin therapy are common and often preventable in the nursing home setting. Prevention strategies should target the prescribing and monitoring stages of warfarin management. Concerns relating to the risks of anticoagulation therapy with warfarin are intensified in the long-term care setting, because elderly residents of nursing homes are among the most frail patients in the geriatric population. Given that more than 1.6 million Americans currently reside in nursing homes and the prevalence of medical conditions for which warfarin is indicated increases with advancing age, issues surrounding the management of anticoagulation therapy in
doi:10.1016/j.amjmed.2006.07.045 pmid:17524757 fatcat:yeb2cyoktbfbxocem6wobiysna

Release Strategies and the Social Impacts of Language Models [article]

Irene Solaiman, Miles Brundage, Jack Clark, Amanda Askell, Ariel Herbert-Voss, Jeff Wu, Alec Radford, Gretchen Krueger, Jong Wook Kim, Sarah Kreps, Miles McCain, Alex Newhouse (+3 others)
2019 arXiv   pre-print
[64] Alec Radford. Language models and their uses. Apr 2019. URL . (Accessed on 08/19/2019). [65] Alec Radford, Jeffrey Wu, et al. Language models are unsupervised multitask learners. 2019.  ...  Abigail See, Stephen Roller, Douwe Kiela, and Jason Weston. What makes a good conversation? How controllable attributes affect human judgments. arXiv preprint arXiv:1902.08654, 2019.  ... 
arXiv:1908.09203v2 fatcat:6c2qqp32h5ax7m6xg5conmmqge

Sustained translational repression by eIF2α-P mediates prion neurodegeneration

Julie A. Moreno, Helois Radford, Diego Peretti, Joern R. Steinert, Nicholas Verity, Maria Guerra Martin, Mark Halliday, Jason Morgan, David Dinsdale, Catherine A. Ortori, David A. Barrett, Pavel Tsaytler (+4 others)
2012 Nature  
The mechanisms leading to neuronal death in neurodegenerative disease are poorly understood. Many of these disorders, including Alzheimer's, Parkinson's and prion diseases, are associated with the accumulation of misfolded disease-specific proteins. The unfolded protein response is a protective cellular mechanism triggered by rising levels of misfolded proteins. One arm of this pathway results in the transient shutdown of protein translation, through phosphorylation of the a-subunit of
more » ... c translation initiation factor, eIF2. Activation of the unfolded protein response and/or increased eIF2a-P levels are seen in patients with Alzheimer's, Parkinson's and prion diseases 1-4 , but how this links to neurodegeneration is unknown. Here we show that accumulation of prion protein during prion replication causes persistent translational repression of global protein synthesis by eIF2a-P, associated with synaptic failure and neuronal loss in prion-diseased mice. Further, we show that promoting translational recovery in hippocampi of prion-infected mice is neuroprotective. Overexpression of GADD34, a specific eIF2a-P phosphatase, as well as reduction of levels of prion protein by lentivirally mediated RNA interference, reduced eIF2a-P levels. As a result, both approaches restored vital translation rates during prion disease, rescuing synaptic deficits and neuronal loss, thereby significantly increasing survival. In contrast, salubrinal, an inhibitor of eIF2a-P dephosphorylation 5 , increased eIF2a-P levels, exacerbating neurotoxicity and significantly reducing survival in priondiseased mice. Given the prevalence of protein misfolding and activation of the unfolded protein response in several neurodegenerative diseases, our results suggest that manipulation of common pathways such as translational control, rather than disease-specific approaches, may lead to new therapies preventing synaptic failure and neuronal loss across the spectrum of these disorders. Neurodegenerative diseases pose an ever-increasing challenge for society and health care systems worldwide, but their molecular pathogenesis is still largely unknown and no curative treatments exist. Alzheimer's (AD), Parkinson's (PD) and prion diseases are separate clinical and pathological conditions, but it is likely they share common mechanisms leading to neuronal death. Mice with prion disease show misfolded prion protein (PrP) accumulation and develop extensive neurodegeneration (with profound neurological deficits), in contrast to mouse models of AD or PD, in which neuronal loss is rare. Uniquely therefore, prion-infected mice allow access to mechanisms linking protein misfolding with neuronal death. Prion replication involves the conversion of cellular PrP, PrP C , to its misfolded, aggregating conformer, PrP Sc , a process leading ultimately to neurodegeneration 6 . We have previously shown rescue of neuronal loss and reversal of early cognitive and morphological changes in prion-infected mice by depleting PrP in neurons, preventing prion replication and abrogating neurotoxicity 7-9 . However, the molecular mechanisms underlying both the progression of disease, and those underlying recovery in PrP-depleted animals, were unknown. To understand these processes better, we now analysed the evolution of neurodegeneration in prion-diseased mice. We examined hippocampi from prion-infected tg37 mice used in our previous experiments [7] [8] [9] [10]
doi:10.1038/nature11058 pmid:22622579 pmcid:PMC3378208 fatcat:nsf5ouujlnc73nfa6qlylec42i

Theory In, Theory Out: The uses of social theory in machine learning for social science [article]

Jason Radford, Kenneth Joseph
2020 arXiv   pre-print
Research at the intersection of machine learning and the social sciences has provided critical new insights into social behavior. At the same time, a variety of critiques have been raised ranging from technical issues with the data used and features constructed, problematic assumptions built into models, their limited interpretability, and their contribution to bias and inequality. We argue such issues arise primarily because of the lack of social theory at various stages of the model building
more » ... nd analysis. In the first half of this paper, we walk through how social theory can be used to answer the basic methodological and interpretive questions that arise at each stage of the machine learning pipeline. In the second half, we show how theory can be used to assess and compare the quality of different social learning models, including interpreting, generalizing, and assessing the fairness of models. We believe this paper can act as a guide for computer and social scientists alike to navigate the substantive questions involved in applying the tools of machine learning to social data.
arXiv:2001.03203v3 fatcat:wl63ycnha5ajhgdgpb54f54shm

Erratum: Corrigendum: Sustained translational repression by eIF2α-P mediates prion neurodegeneration

Julie A. Moreno, Helois Radford, Diego Peretti, Joern R. Steinert, Nicholas Verity, Maria Guerra Martin, Mark Halliday, Jason Morgan, David Dinsdale, Catherine A. Ortori, David A. Barrett, Pavel Tsaytler (+4 others)
2014 Nature  
doi:10.1038/nature13569 fatcat:4gmolzcemzfilhohfgzfn6cbha

The Golem Group/University of California at Los Angeles autonomous ground vehicle in the DARPA grand challenge

Richard Mason, Jim Radford, Deepak Kumar, Robert Walters, Brian Fulkerson, Eagle Jones, David Caldwell, Jason Meltzer, Yaniv Alon, Amnon Shashua, Hiroshi Hattori, Emilio Frazzoli (+1 others)
2006 Journal of Field Robotics  
This paper presents the Golem Group/University of California at Los Angeles entry to the 2005 DARPA Grand Challenge competition. We describe the main design principles behind the development of Golem 2, the race vehicle. The subsystems devoted to obstacle detection, avoidance, and state estimation are discussed in more detail. An overview of vehicle performance in the field is provided, including successes together with an analysis of the reasons leading to failures.
doi:10.1002/rob.20137 fatcat:oesi6iqjurfileuv4xctduwlim

Environmental Factors Controlling the Distribution of Symbiodinium Harboured by the Coral Acropora millepora on the Great Barrier Reef

Timothy F. Cooper, Ray Berkelmans, Karin E. Ulstrup, Scarla Weeks, Ben Radford, Alison M. Jones, Jason Doyle, Marites Canto, Rebecca A. O'Leary, Madeleine J. H. van Oppen, Terence Evens
2011 PLoS ONE  
The Symbiodinium community associated with scleractinian corals is widely considered to be shaped by seawater temperature, as the coral's upper temperature tolerance is largely contingent on the Symbiodinium types harboured. Few studies have challenged this paradigm as knowledge of other environmental drivers on the distribution of Symbiodinium is limited. Here, we examine the influence of a range of environmental variables on the distribution of Symbiodinium associated with Acropora millepora
more » ... ollected from 47 coral reefs spanning 1,400 km on the Great Barrier Reef (GBR), Australia. Methodology/Principal Findings: The environmental data included Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data at 1 km spatial resolution from which a number of sea surface temperature (SST) and water quality metrics were derived. In addition, the carbonate and mud composition of sediments were incorporated into the analysis along with in situ water quality samples for a subset of locations. Analyses were conducted at three spatio-temporal scales [GBR (regional-scale), Whitsunday Islands (local-scale) and Keppel Islands/Trunk Reef (temporal)] to examine the effects of scale on the distribution patterns. While SST metrics were important drivers of the distribution of Symbiodinium types at regional and temporal scales, our results demonstrate that spatial variability in water quality correlates significantly with Symbiodinium distribution at local scales. Background levels of Symbiodinium types were greatest at turbid inshore locations of the Whitsunday Islands where SST predictors were not as important. This was not the case at regional scales where combinations of mud and carbonate sediment content coupled with SST anomalies and mean summer SST explained 51.3% of the variation in dominant Symbiodinium communities. Conclusions/Significance: Reef corals may respond to global-scale stressors such as climate change through changes in their resident symbiont communities, however, management of local-scale stressors such as altered water quality is also necessary for maintenance of coral-Symbiodinium associations.
doi:10.1371/journal.pone.0025536 pmid:22065989 pmcid:PMC3204971 fatcat:3sd55salfzathovnsiitsweh6a

Effect of BDNF Val66Met on disease markers in dominantly inherited Alzheimer's disease

Yen Ying Lim, Jason Hassenstab, Alison Goate, Anne M. Fagan, Tammie L.S. Benzinger, Carlos Cruchaga, Eric McDade, Jasmeer Chhatwal, Johannes Levin, Martin R. Farlow, Neill R. Graff-Radford, Christoph Laske (+6 others)
2018 Annals of Neurology  
Objective. Previous studies suggest that the brain-derived neurotrophic factor (BDNF) Val66Met (rs6265) polymorphism may influence symptom onset in Alzheimer's disease (AD). Our recent cross-sectional findings suggest that Met66 may influence clinical expression in dominantly inherited AD (DIAD) through its effects on tau. However, it remains unclear whether carriage of Met66 in DIAD results in faster increases in CSF tau and ptau 181 , and whether these increases are associated with
more » ... brain volume loss and memory decline. Methods. A total of 211 subjects (101 mutation non-carriers, 110 mutation carriers), who were cognitively normal, as defined by a Clinical Dementia Rating (CDR) global score of 0, completed assessments of cognitive function, neuroimaging and CSF sampling over 3.5 years as part of the Dominantly Inherited Alzheimer's Network (DIAN). Results. In mutation carriers, Met66 carriers showed faster memory decline (4x), hippocampal volume loss (16x), and CSF tau and ptau 181 increases (6x) than Val66 homozygotes. BDNF did not influence rates of cortical β-amyloid accumulation or change in CSF Aβ 42 levels in mutation carriers. In mutation non-carriers, BDNF genotype had no effect on change in cognition, brain volume, cortical β-amyloid accumulation or change in any CSF measures of tau, ptau 181 , and CSF Aβ 42 . Interpretation. As in sporadic AD, the deleterious effects of β-amyloid on cognitive function, brain volume loss and CSF tau in DIAD mutation carriers are less in Val66 homozygotes. The BDNF Val66Met polymorphism should be considered as a potential moderator of clinical trial outcomes in current treatment and prevention trials in DIAD and sporadic AD.
doi:10.1002/ana.25299 pmid:30014553 fatcat:6ac7irv5yraizmojcxou5b4iiu

An Integrated Characterization of Serological, Pathological, and Functional Events in Doxorubicin-Induced Cardiotoxicity

Laura Cove-Smith, Neil Woodhouse, Adam Hargreaves, Jason Kirk, Susan Smith, Sally A. Price, Melanie Galvin, Catherine J. Betts, Simon Brocklehurst, Alison Backen, John Radford, Kim Linton (+6 others)
2014 Toxicological Sciences  
Many efficacious cancer treatments cause significant cardiac morbidity, yet biomarkers or functional indices of early damage, which would allow monitoring and intervention, are lacking. In this study, we have utilized a rat model of progressive doxorubicin (DOX)-induced cardiomyopathy, applying multiple approaches, including cardiac magnetic resonance imaging (MRI), to provide the most comprehensive characterization to date of the timecourse of serological, pathological, and functional events
more » ... derlying this toxicity. Hannover Wistar rats were dosed with 1.25 mg/kg DOX weekly for 8 weeks followed by a 4 week off-dosing "recovery" period. Electron microscopy of the myocardium revealed subcellular degeneration and marked mitochondrial changes after a single dose. Histopathological analysis revealed progressive cardiomyocyte degeneration, hypertrophy/cytomegaly, and extensive vacuolation after two doses. Extensive replacement fibrosis (quantified by Sirius red staining) developed during the off-dosing period. Functional indices assessed by cardiac MRI (including left ventricular ejection fraction (LVEF), cardiac output, and E/A ratio) declined progressively, reaching statistical significance after two doses and culminating in "clinical" LV dysfunction by 12 weeks. Significant increases in peak myocardial contrast enhancement and serological cardiac troponin I (cTnI) emerged after eight doses, importantly preceding the LVEF decline to <50%. Troponin I levels positively correlated with delayed and peak gadolinium contrast enhancement, histopathological grading, and diastolic dysfunction. In summary, subcellular cardiomyocyte degeneration was the earliest marker, followed by progressive functional decline and histopathological manifestations. Myocardial contrast enhancement and elevations in cTnI occurred later. However, all indices predated "clinical" LV dysfunction and thus warrant further evaluation as predictive biomarkers.
doi:10.1093/toxsci/kfu057 pmid:24675088 fatcat:gtb5rlcchbfnnphucfhm72t7pu
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