10,690 research outputs found
Six-year mortality in a street-recruited cohort of homeless youth in San Francisco, California.
Objectives. The mortality rate of a street-recruited homeless youth cohort in the United States has not yet been reported. We examined the six-year mortality rate for a cohort of street youth recruited from San Francisco street venues in 2004. Methods. Using data collected from a longitudinal, venue-based sample of street youth 15-24 years of age, we calculated age, race, and gender-adjusted mortality rates. Results. Of a sample of 218 participants, 11 died from enrollment in 2004 to December 31, 2010. The majority of deaths were due to suicide and/or substance abuse. The death rate was 9.6 deaths per hundred thousand person-years. The age, race and gender-adjusted standardized mortality ratio was 10.6 (95% CI [5.3-18.9]). Gender specific SMRs were 16.1 (95% CI [3.3-47.1]) for females and 9.4 (95% CI [4.0-18.4]) for males. Conclusions. Street-recruited homeless youth in San Francisco experience a mortality rate in excess of ten times that of the states general youth population. Services and programs, particularly housing, mental health and substance abuse interventions, are urgently needed to prevent premature mortality in this vulnerable population
Failure dynamics of the global risk network
Risks threatening modern societies form an intricately interconnected network
that often underlies crisis situations. Yet, little is known about how risk
materializations in distinct domains influence each other. Here we present an
approach in which expert assessments of risks likelihoods and influence
underlie a quantitative model of the global risk network dynamics. The modeled
risks range from environmental to economic and technological and include
difficult to quantify risks, such as geo-political or social. Using the maximum
likelihood estimation, we find the optimal model parameters and demonstrate
that the model including network effects significantly outperforms the others,
uncovering full value of the expert collected data. We analyze the model
dynamics and study its resilience and stability. Our findings include such risk
properties as contagion potential, persistence, roles in cascades of failures
and the identity of risks most detrimental to system stability. The model
provides quantitative means for measuring the adverse effects of risk
interdependence and the materialization of risks in the network
Personalizing Dialogue Agents via Meta-Learning
Existing personalized dialogue models use human designed persona descriptions
to improve dialogue consistency. Collecting such descriptions from existing
dialogues is expensive and requires hand-crafted feature designs. In this
paper, we propose to extend Model-Agnostic Meta-Learning (MAML)(Finn et al.,
2017) to personalized dialogue learning without using any persona descriptions.
Our model learns to quickly adapt to new personas by leveraging only a few
dialogue samples collected from the same user, which is fundamentally different
from conditioning the response on the persona descriptions. Empirical results
on Persona-chat dataset (Zhang et al., 2018) indicate that our solution
outperforms non-meta-learning baselines using automatic evaluation metrics, and
in terms of human-evaluated fluency and consistency.Comment: Accepted in ACL 2019. Zhaojiang Lin* and Andrea Madotto* contributed
equally to this wor
Effect of Human Capital on the Entrepreneurship Gender Gap
The presence of a gender gap in entrepreneurship has been well studied in previous literature. There are various contributing factors, including differences in human capital, which has been reviewed less so than social capital. Through a career survey of Wharton MBAs, this research paper 1) examines the presence of an entrepreneurship gender gap; 2) identifies human capital variables that predict entry into entrepreneurship; and 3) determines whether or not there is a human capital gender gap. The results showed both an entrepreneurship and human capital gender gap. Furthermore, experience working at small companies, more years of experience, and experience in finance-related industries were found to be good predictors of entry. Overall, the human capital predictor model explained 6.4% of the variability of entry into entrepreneurship. Though applicability is limited due to the biases of the sample, there are tangible implications for decreasing the entrepreneurship gender gap
NNLL Momentum-Space Resummation for Stop-Pair Production at the LHC
If supersymmetry near the TeV scale is realized in Nature, the pair
production of scalar top squarks is expected to be observable at the Large
Hadron Collider. Recently, effective field-theory methods were employed to
obtain approximate predictions for the cross section for this process, which
include soft-gluon emission effects up to next-to-next-to-leading order (NNLO)
in perturbation theory. In this work we employ the same techniques to resum
soft-gluon emission effects to all orders in perturbation theory and with
next-to-next-to-logarithmic (NNLL) accuracy. We analyze the effects of NNLL
resummation on the stop-pair production cross section by obtaining NLO+NNLL
predictions in pair invariant mass and one-particle inclusive kinematics. We
compare the results of these calculations to the approximate NNLO predictions
for the cross sections.Comment: 25 pages, 6 figure
Approximate NNLO Predictions for the Stop-Pair Production Cross Section at the LHC
If the minimal supersymmetric standard model at scales of around 1 TeV is
realized in nature, the total top-squark pair production cross section should
be measurable at the CERN Large Hadron Collider. In this work we present
precise predictions for this observable, which are based upon approximate NNLO
formulas obtained using soft-collinear effective theory methods.Comment: 36 pages, 7 figures and 11 tables. Version published in JHEP 1307
(2013) 04
Between a Rock and a Cell Phone: Social Media Use during Mass Protests in Iran, Tunisia and Egypt
In this paper we examine the use of social media, and especially Twitter, in Iran, Tunisia and Egypt during the mass political demonstrations and protests in June 2009, December 2010 - January 2011, and February 2011, respectively. We compare this usage with methods and findings from other studies on the use of Twitter in emergency situations, such as natural and man-made disasters. We draw on our own experiences and participant-observations as an eyewitness in Iran (first author), and on Twitter data from Iran, Tunisia and Egypt. In these three cases, Twitter filled a unique technology and communication gap at least partially. We summarize suggested directions for future research with a view of placing this work in the larger context of social media use in conditions of crisis and social convergence
The Impact of Regional Food Cost Differences on the TFP Recommendations
The Thrifty Food Plan (TFP) adapts a national average price and stipulates that all foods should be prepared at home (FAH). Our purpose was to calculate the TFP with regional prices and add Food Away From Home (FAFH) into the TFP model. Measures were calculated and compared across the TFP, the regional models with FAFH, and low-income consumers’ diet pattern. The preliminary results indicated that considering moderate FAFH in the TFP yielded similar nutrient and food group composition as the TFP with FAFH added in it, while greatly increased the practicality and adaptability of the recommendations. However, the regional TFP costs are all larger than the TFP with FAFH cost. These findings may be used by nutrition educators to develop healthful FAFH choices and readjust the TFP allotments for Supplemental Nutrition Assistance Program (SNAP) participants.Regional, Food Cost, The TFP, Consumer/Household Economics, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, Health Economics and Policy,
Multimedia Semantic Integrity Assessment Using Joint Embedding Of Images And Text
Real world multimedia data is often composed of multiple modalities such as
an image or a video with associated text (e.g. captions, user comments, etc.)
and metadata. Such multimodal data packages are prone to manipulations, where a
subset of these modalities can be altered to misrepresent or repurpose data
packages, with possible malicious intent. It is, therefore, important to
develop methods to assess or verify the integrity of these multimedia packages.
Using computer vision and natural language processing methods to directly
compare the image (or video) and the associated caption to verify the integrity
of a media package is only possible for a limited set of objects and scenes. In
this paper, we present a novel deep learning-based approach for assessing the
semantic integrity of multimedia packages containing images and captions, using
a reference set of multimedia packages. We construct a joint embedding of
images and captions with deep multimodal representation learning on the
reference dataset in a framework that also provides image-caption consistency
scores (ICCSs). The integrity of query media packages is assessed as the
inlierness of the query ICCSs with respect to the reference dataset. We present
the MultimodAl Information Manipulation dataset (MAIM), a new dataset of media
packages from Flickr, which we make available to the research community. We use
both the newly created dataset as well as Flickr30K and MS COCO datasets to
quantitatively evaluate our proposed approach. The reference dataset does not
contain unmanipulated versions of tampered query packages. Our method is able
to achieve F1 scores of 0.75, 0.89 and 0.94 on MAIM, Flickr30K and MS COCO,
respectively, for detecting semantically incoherent media packages.Comment: *Ayush Jaiswal and Ekraam Sabir contributed equally to the work in
this pape
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