Showing papers by "Paris Dauphine University published in 2021"

MDETR -- Modulated Detection for End-to-End Multi-Modal Understanding.

Abstract: Multi-modal reasoning systems rely on a pre-trained object detector to extract regions of interest from the image. However, this crucial module is typically used as a black box, trained independently of the downstream task and on a fixed vocabulary of objects and attributes. This makes it challenging for such systems to capture the long tail of visual concepts expressed in free form text. In this paper we propose MDETR, an end-to-end modulated detector that detects objects in an image conditioned on a raw text query, like a caption or a question. We use a transformer-based architecture to reason jointly over text and image by fusing the two modalities at an early stage of the model. We pre-train the network on 1.3M text-image pairs, mined from pre-existing multi-modal datasets having explicit alignment between phrases in text and objects in the image. We then fine-tune on several downstream tasks such as phrase grounding, referring expression comprehension and segmentation, achieving state-of-the-art results on popular benchmarks. We also investigate the utility of our model as an object detector on a given label set when fine-tuned in a few-shot setting. We show that our pre-training approach provides a way to handle the long tail of object categories which have very few labelled instances. Our approach can be easily extended for visual question answering, achieving competitive performance on GQA and CLEVR. The code and models are available at this https URL.

Income and wealth distribution in macroeconomics: a continuous-time approach

Abstract: We recast the Aiyagari-Bewley-Huggett model of income and wealth distribution in continuous time. This workhorse model – as well as heterogeneous agent models more generally – then boils down to a system of partial differential equations, a fact we take advantage of to make two types of contributions. First, a number of new theoretical results: (i) an analytic characterization of the consumption and saving behavior of the poor, particularly their marginal propensities to consume; (ii) a closed-form solution for the wealth distribution in a special case with two income types; (iii) a proof that there is a unique stationary equilibrium if the intertemporal elasticity of substitution is weakly greater than one; (iv) characterization of “soft” borrowing constraints. Second, we develop a simple, efficient and portable algorithm for numerically solving for equilibria in a wide class of heterogeneous agent models, including – but not limited to – the Aiyagari-Bewley-Huggett model.

Turnover Modulates the Need for a Cost of Resistance in Adaptive Therapy.

Abstract: Adaptive therapy seeks to exploit intratumoral competition to avoid, or at least delay, the emergence of therapy resistance in cancer. Motivated by promising results in prostate cancer, there is growing interest in extending this approach to other neoplasms. As such, it is urgent to understand the characteristics of a cancer that determine whether or not it will respond well to adaptive therapy. A plausible candidate for such a selection criterion is the fitness cost of resistance. In this article, we study a general, but simple, mathematical model to investigate whether the presence of a cost is necessary for adaptive therapy to extend the time to progression beyond that of a standard-of-care continuous therapy. Tumor cells were divided into sensitive and resistant populations and we model their competition using a system of two ordinary differential equations based on the Lotka-Volterra model. For tumors close to their environmental carrying capacity, a cost was not required. However, for tumors growing far from carrying capacity, a cost may be required to see meaningful gains. Notably, it is important to consider cell turnover in the tumor, and we discuss its role in modulating the impact of a resistance cost. To conclude, we present evidence for the predicted cost-turnover interplay in data from 67 patients with prostate cancer undergoing intermittent androgen deprivation therapy. Our work helps to clarify under which circumstances adaptive therapy may be beneficial and suggests that turnover may play an unexpectedly important role in the decision-making process. SIGNIFICANCE: Tumor cell turnover modulates the speed of selection against drug resistance by amplifying the effects of competition and resistance costs; as such, turnover is an important factor in resistance management via adaptive therapy.See related commentary by Strobl et al., p. 811.

Corrigendum to: Antibody status and cumulative incidence of SARS-CoV-2 infection among adults in three regions of France following the first lockdown and associated risk factors: a multicohort study.

Abstract: BACKGROUND: We aimed to estimate the seropositivity to anti-SARS-CoV-2 antibodies in May-June 2020 after the first lockdown period in adults living in three regions in France and to identify the associated risk factors. METHODS: Between 4 May 2020 and 23 June 2020, 16 000 participants in a survey on COVID-19 from an existing consortium of three general adult population cohorts living in the Ile-de-France (IDF) or Grand Est (GE) (two regions with high rate of COVID-19) or in the Nouvelle-Aquitaine (NA) (with a low rate) were randomly selected to take a dried-blood spot for anti-SARS-CoV-2 antibodies assessment with three different serological methods (ClinicalTrial Identifier #NCT04392388). The primary outcome was a positive anti-SARS-CoV-2 ELISA IgG result against the spike protein of the virus (ELISA-S). Estimates were adjusted using sampling weights and post-stratification methods. Multiple imputation was used to infer the cumulative incidence of SARS-CoV-2 infection with adjustments for imperfect tests accuracies. RESULTS: The analysis included 14 628 participants, 983 with a positive ELISA-S. The weighted estimates of seropositivity and cumulative incidence were 10.0% [95% confidence interval (CI): 9.1%, 10.9%] and 11.4% (95% CI: 10.1%, 12.8%) in IDF, 9.0% (95% CI: 7.7%, 10.2%) and 9.8% (95% CI: 8.1%, 11.8%) in GE and 3.1% (95% CI: 2.4%, 3.7%) and 2.9% (95% CI: 2.1%, 3.8%) in NA, respectively. Seropositivity was higher in younger participants [odds ratio (OR) = 1.84 (95% CI: 1.79, 6.09) in <40 vs 50-60 years old and OR = 0.56 (95% CI: 0.42, 0.74) in ≥70 vs 50-60 years old)] and when at least one child or adolescent lived in the same household [OR = 1.30 (95% CI: 1.11, 1.53)] and was lower in smokers compared with non-smokers [OR = 0.71 (95% CI: 0.57, 0.49)]. CONCLUSIONS: Seropositivity to anti-SARS-CoV-2 antibodies in the French adult population was ≤10% after the first wave. Modifiable and non-modifiable risk factors were identified.

When lockdown policies amplify social inequalities in COVID-19 infections: evidence from a cross-sectional population-based survey in France.

Abstract: Significant differences in COVID-19 incidence by gender, class and race/ethnicity are recorded in many countries in the world. Lockdown measures, shown to be effective in reducing the number of new cases, may not have been effective in the same way for all, failing to protect the most vulnerable populations. This survey aims to assess social inequalities in the trends in COVID-19 infections following lockdown. A cross-sectional survey conducted among the general population in France in April 2020, during COVID-19 lockdown. Ten thousand one hundred one participants aged 18–64, from a national cohort who lived in the three metropolitan French regions most affected by the first wave of COVID-19. The main outcome was occurrence of possible COVID-19 symptoms, defined as the occurrence of sudden onset of cough, fever, dyspnea, ageusia and/or anosmia, that lasted more than 3 days in the 15 days before the survey. We used multinomial regression models to identify social and health factors related to possible COVID-19 before and during the lockdown. In all, 1304 (13.0%; 95% CI: 12.0–14.0%) reported cases of possible COVID-19. The effect of lockdown on the occurrence of possible COVID-19 was different across social hierarchies. The most privileged class individuals saw a significant decline in possible COVID-19 infections between the period prior to lockdown and during the lockdown (from 8.8 to 4.3%, P = 0.0001) while the decline was less pronounced among working class individuals (6.9% before lockdown and 5.5% during lockdown, P = 0.03). This differential effect of lockdown remained significant after adjusting for other factors including history of chronic disease. The odds of being infected during lockdown as opposed to the prior period increased by 57% among working class individuals (OR = 1.57; 95% CI: 1.00–2.48). The same was true for those engaged in in-person professional activities during lockdown (OR = 1.53; 95% CI: 1.03–2.29). Lockdown was associated with social inequalities in the decline in COVID-19 infections, calling for the adoption of preventive policies to account for living and working conditions. Such adoptions are critical to reduce social inequalities related to COVID-19, as working-class individuals also have the highest COVID-19 related mortality, due to higher prevalence of comorbidities.

Control and Surveillance in Work Practice: Cultivating Paradox in ‘New’ Modes of Organizing:

Abstract: The new world of work is being characterized by the emergence of what are, apparently, increasingly autonomous ways of working and living. Mobile work, coworking, flex office, platform-based entrepreneurship, virtual collaborations, Do It Yourself (DIT), remote work, digital nomads, among other trends, epitomize ways of organizing work practice that purportedly align productivity with freedom. But most ethnographical research already reveals many paradoxical experiences associated with these new practices and processes. Indeed, it appears that with autonomy comes surveillance and control, to a point where, as Foucault observed way back, subjectivity and subject become synonyms, and the current pandemic both strengthens and makes visible this situation. In this introduction to the special issue we make a foray into this situation, using four open and related themes developed in the five papers we selected: managerial control and technology; surveillance and platform capitalism; time and space; and new organizational forms and autonomy. Paradoxical movements are identified for each of them, before we conclude by reflecting on a grounding paradox which appears at the centre of this special issue and the themes it covers.

Prophet secretary through blind strategies

Abstract: In the classic prophet inequality, a well-known problem in optimal stopping theory, samples from independent random variables (possibly differently distributed) arrive online. A gambler who knows the distributions, but cannot see the future, must decide at each point in time whether to stop and pick the current sample or to continue and lose that sample forever. The goal of the gambler is to maximize the expected value of what she picks and the performance measure is the worst case ratio between the expected value the gambler gets and what a prophet that sees all the realizations in advance gets. In the late seventies, Krengel and Sucheston (Bull Am Math Soc 83(4):745–747, 1977), established that this worst case ratio is 0.5. A particularly interesting variant is the so-called prophet secretary problem, in which the only difference is that the samples arrive in a uniformly random order. For this variant several algorithms are known to achieve a constant of $$1-1/e \approx 0.632$$ and very recently this barrier was slightly improved by Azar et al. (in: Proceedings of the ACM conference on economics and computation, EC, 2018). In this paper we introduce a new type of multi-threshold strategy, called blind strategy. Such a strategy sets a nonincreasing sequence of thresholds that depends only on the distribution of the maximum of the random variables, and the gambler stops the first time a sample surpasses the threshold of the stage. Our main result shows that these strategies can achieve a constant of 0.669 for the prophet secretary problem, improving upon the best known result of Azar et al. (in: Proceedings of the ACM conference on economics and computation, EC, 2018), and even that of Beyhaghi et al. (Improved approximations for posted price and second price mechanisms. CoRR arXiv:1807.03435 , 2018) that works in the case in which the gambler can select the order of the samples. The crux of the result is a very precise analysis of the underlying stopping time distribution for the gambler’s strategy that is inspired by the theory of Schur-convex functions. We further prove that our family of blind strategies cannot lead to a constant better than 0.675. Finally we prove that no algorithm for the gambler can achieve a constant better than $$\sqrt{3}-1 \approx 0.732$$ , which also improves upon a recent result of Azar et al. (in: Proceedings of the ACM conference on economics and computation, EC, 2018). This implies that the upper bound on what the gambler can get in the prophet secretary problem is strictly lower than what she can get in the i.i.d. case. This constitutes the first separation between the prophet secretary problem and the i.i.d. prophet inequality.

Twin-width II: small classes

Abstract: The twin-width of a graph $G$ is the minimum integer $d$ such that $G$ has a $d$-contraction sequence, that is, a sequence of $|V(G)|-1$ iterated vertex identifications for which the overall maximum number of red edges incident to a single vertex is at most $d$, where a red edge appears between two sets of identified vertices if they are not homogeneous in $G$. We show that if a graph admits a $d$-contraction sequence, then it also has a linear-arity tree of $f(d)$-contractions, for some function $f$. First this permits to show that every bounded twin-width class is small, i.e., has at most $n!c^n$ graphs labeled by $[n]$, for some constant $c$. This unifies and extends the same result for bounded treewidth graphs [Beineke and Pippert, JCT '69], proper subclasses of permutations graphs [Marcus and Tardos, JCTA '04], and proper minor-free classes [Norine et al., JCTB '06]. The second consequence is an $O(\log n)$-adjacency labeling scheme for bounded twin-width graphs, confirming several cases of the implicit graph conjecture. We then explore the "small conjecture" that, conversely, every small hereditary class has bounded twin-width. Inspired by sorting networks of logarithmic depth, we show that $\log_{\Theta(\log \log d)}n$-subdivisions of $K_n$ (a small class when $d$ is constant) have twin-width at most $d$. We obtain a rather sharp converse with a surprisingly direct proof: the $\log_{d+1}n$-subdivision of $K_n$ has twin-width at least $d$. Secondly graphs with bounded stack or queue number (also small classes) have bounded twin-width. Thirdly we show that cubic expanders obtained by iterated random 2-lifts from $K_4$~[Bilu and Linial, Combinatorica '06] have bounded twin-width, too. We suggest a promising connection between the small conjecture and group theory. Finally we define a robust notion of sparse twin-width and discuss how it compares with other sparse classes.

A theoretical analysis of tumour containment.

Abstract: Recent studies have shown that a strategy aiming for containment, not elimination, can control tumour burden more effectively in vitro, in mouse models and in the clinic. These outcomes are consistent with the hypothesis that emergence of resistance to cancer therapy may be prevented or delayed by exploiting competitive ecological interactions between drug-sensitive and drug-resistant tumour cell subpopulations. However, although various mathematical and computational models have been proposed to explain the superiority of particular containment strategies, this evolutionary approach to cancer therapy lacks a rigorous theoretical foundation. Here we combine extensive mathematical analysis and numerical simulations to establish general conditions under which a containment strategy is expected to control tumour burden more effectively than applying the maximum tolerated dose. We show that containment may substantially outperform more aggressive treatment strategies even if resistance incurs no cellular fitness cost. We further provide formulas for predicting the clinical benefits attributable to containment strategies in a wide range of scenarios and compare the outcomes of theoretically optimal treatments with those of more practical protocols. Our results strengthen the rationale for clinical trials of evolutionarily informed cancer therapy, while also clarifying conditions under which containment might fail to outperform standard of care. Adaptive therapies based on evolutionary principles propose that, under certain conditions, tumour containment, rather than elimination, might be the best strategy to treat cancer. This study presents a theoretical analysis of different models of tumour containment.

Biased Aspirations and Social Inequality at School: Evidence from French Teenagers

Abstract: Socially disadvantaged students are less likely to aspire to the top educational pathways than their advantaged classmates who have the same test scores We identify two behavioural biases that explain most of this gap: socially disadvantaged students are less aware of the top educational pathways and underestimate their academic ability relative to their advantaged peers We also find that lower educational aspirations at a point in time are associated with poorer school outcomes later on, after controlling for many important factors Debiasing aspirations through information campaigns and self-esteem building programmes could thus help reduce social inequality in educational attainment

Incidence and risk factors of COVID-19-like symptoms in the French general population during the lockdown period: a multi-cohort study.

Abstract: Background Our main objectives were to estimate the incidence of illnesses presumably caused by SARS-CoV-2 infection during the lockdown period and to identify the associated risk factors Methods Participants from 3 adult cohorts in the general population in France were invited to participate in a survey on COVID-19 The main outcome was COVID-19-Like Symptoms (CLS), defined as a sudden onset of cough, fever, dyspnea, ageusia and/or anosmia, that lasted more than 3 days and occurred during the 17 days before the survey We used delayed-entry Cox models to identify associated factors Results Between April 2, 2020 and May 12, 2020, 279,478 participants were invited, 116,903 validated the questionnaire and 106,848 were included in the analysis Three thousand thirty-five cases of CLS were reported during 62,099 person-months of follow-up The cumulative incidences of CLS were 62% (95% Confidence Interval (95%CI): 57%; 66%) on day 15 and 88% (95%CI 83%; 92%) on day 45 of lockdown The risk of CLS was lower in older age groups and higher in French regions with a high prevalence of SARS-CoV-2 infection, in participants living in cities > 100,000 inhabitants (vs rural areas), when at least one child or adolescent was living in the same household, in overweight or obese people, and in people with chronic respiratory diseases, anxiety or depression or chronic diseases other than diabetes, cancer, hypertension or cardiovascular diseases Conclusion The incidence of CLS in the general population remained high during the first 2 weeks of lockdown, and decreased significantly thereafter Modifiable and non-modifiable risk factors were identified

Assistive robots to improve the independent living of older persons: results from a needs study

Abstract: More than 70% of elderly people age 80 and older are experiencing problems in personal mobility. Assistive robotics can represent a concrete support providing also a support for caregivers, clinici...

Dirac operators and shell interactions: a survey

Abstract: In this survey we gather recent results on Dirac operators coupled with δ-shell interactions. We start by discussing recent advances regarding the question of self-adjointness for these operators. Afterwards we switch to an approximation question: can these operators be recovered as limits of Dirac operators coupled with squeezing potentials? We also discuss spectral features of these models. Namely, we recall the main spectral consequences of a resolvent formula and conclude the survey by commenting a result of asymptotic nature for the eigenvalues in the gap of a Dirac operator coupled with a Lorentz-scalar interaction.

A political anthropology of finance: Studying the distribution of money in the financial industry as a political process:

Abstract: This article proposes an analytics to study the financial industry as a global political institution, based on its role in the production of global hierarchies, by the way it collects, produces and...

Edoxaban for stroke prevention in atrial fibrillation in routine clinical care: 1-year follow-up of the prospective observational ETNA-AF-Europe study.

Abstract: AIM Non-vitamin K oral anticoagulants (NOACs) are safe and effective for stroke prevention in patients with atrial fibrillation (AF). Data on the safety and efficacy of edoxaban in routine care are limited in Europe. We report one-year outcomes in patients with AF treated with edoxaban in routine care. METHODS AND RESULTS ETNA-AF-Europe is a prospective, multi-centre, post-authorisation, observational study enrolling patients treated with edoxaban in 10 European countries, the design of which was agreed with the European Medicines Agency as part of edoxaban's post-approval safety plan.Altogether 13,092 patients in 852 sites completed the one-year follow-up (mean age: 73.6 ± 9.5 years; 57% male, mean follow-up: 352 ± 49 days [median: 366 days]). Most patients had associated comorbidities (mean CHA2DS2-VASc score: 3.1 ± 1.4). Stroke or systemic embolism was reported in 103 patients (annualised event rate: 0.82%/year), and major bleeding events was reported in 132 patients (1.05%/year). Rates of intracranial haemorrhage were low (30 patients [0.24%/year]). Death occurred in 442 patients (3.50%/year); cardiovascular death occurred in 206 patients (1.63%/year). The approved dosing of edoxaban was chosen in 83%. All-cause and cardiovascular mortality were higher in patients receiving edoxaban 30 mg versus 60 mg, in line with the higher age and more frequent comorbidities of the 30 mg group. Major bleeding was also numerically more common in patients receiving edoxaban 30 mg versus 60 mg. CONCLUSION The rates of stroke, systemic embolism and major bleeding are low in this large unselected cohort of high-risk AF patients routinely treated with edoxaban.

Economic vulnerability and unmet healthcare needs among the population aged 50 + years during the COVID-19 pandemic in Europe.

Abstract: This study investigated the effect of economic vulnerability on unmet needs during the first wave of the coronavirus disease 2019 (COVID-19) epidemic in Europe among adults aged 50 years and older using data from the regular administration of the Survey of Health, Ageing and Retirement in Europe (SHARE) and the specific telephone survey administered regarding COVID-19 (SHARE Corona Survey). It addressed three main research questions: Did people who were in difficult economic situations before the epidemic face more barriers to accessing healthcare than others? If so, to what extent can these discrepancies be attributed to initial differences in health status, use of care, income or education between vulnerable individuals and non-vulnerable individuals or to differential effects of the pandemic on these groups? Did the effect of economic vulnerability with regard to unmet needs during the pandemic differ across countries? Unmet healthcare needs are characterised by three types of behaviours likely to be induced by the pandemic: forgoing care for fear of contracting COVID-19, having pre-scheduled care postponed and being unable to obtain medical appointments or treatments when needed. Our results substantiate the existence of significant differences in accessing healthcare during the pandemic according to economic vulnerability and of cumulative effects of economic and medical vulnerabilities: the impact of economic vulnerability is notably stronger among those who were in poor health before the outbreak and thus the oldest individuals. The cross-country comparison highlighted heterogeneous effects of economic vulnerability on forgoing care and having care postponed among countries, which are not comparable to the initial cross-country differences in social inequalities in access to healthcare.

Korn and Poincaré-Korn inequalities for functions with a small jump set

Abstract: In this paper we prove a regularity and rigidity result for displacements in $$GSBD^p$$ , for every $$p>1$$ and any dimension $$n\ge 2$$ . We show that a displacement in $$GSBD^p$$ with a small jump set coincides with a $$W^{1,p}$$ function, up to a small set whose perimeter and volume are controlled by the size of the jump. This generalises to higher dimension a result of Conti, Focardi and Iurlano. A consequence of this is that such displacements satisfy, up to a small set, Poincare-Korn and Korn inequalities. As an application, we deduce an approximation result which implies the existence of the approximate gradient for displacements in $$GSBD^p$$ .

Precise asymptotics: Robust stochastic volatility models

Abstract: We present a new methodology to analyze large classes of (classical and rough) stochastic volatility models, with special regard to short-time and small noise formulae for option prices. Our main tool is the theory of regularity structures, which we use in the form of Bayer et al. (Math. Finance 30 (2020) 782–832) In essence, we implement a Laplace method on the space of models (in the sense of Hairer), which generalizes classical works of Azencott and Ben Arous on path space and then Aida, Inahama–Kawabi on rough path space. When applied to rough volatility models, for example, in the setting of Bayer, Friz and Gatheral (Quant. Finance 16 (2016) 887–904) and Forde–Zhang (SIAM J. Financial Math. 8 (2017) 114–145), one obtains precise asymptotics for European options which refine known large deviation asymptotics.

A Semi-Personalized System for User Cold Start Recommendation on Music Streaming Apps

Abstract: Music streaming services heavily rely on recommender systems to improve their users' experience, by helping them navigate through a large musical catalog and discover new songs, albums or artists. However, recommending relevant and personalized content to new users, with few to no interactions with the catalog, is challenging. This is commonly referred to as the user cold start problem. In this applied paper, we present the system recently deployed on the music streaming service Deezer to address this problem. The solution leverages a semi-personalized recommendation strategy, based on a deep neural network architecture and on a clustering of users from heterogeneous sources of information. We extensively show the practical impact of this system and its effectiveness at predicting the future musical preferences of cold start users on Deezer, through both offline and online large-scale experiments. Besides, we publicly release our code as well as anonymized usage data from our experiments. We hope that this release of industrial resources will benefit future research on user cold start recommendation.

Enumeration of the Nondominated Set of Multiobjective Discrete Optimization Problems

Abstract: In this paper, we propose a generic algorithm to compute exactly the set of nondominated points for multiobjective discrete optimization problems. Our algorithm extends the e-constraint method, ori...

Nonparametric estimation for interacting particle systems: McKean–Vlasov models

Abstract: We consider a system of N interacting particles, governed by transport and diffusion, that converges in a mean-field limit to the solution of a McKean–Vlasov equation. From the observation of a trajectory of the system over a fixed time horizon, we investigate nonparametric estimation of the solution of the associated nonlinear Fokker–Planck equation, together with the drift term that controls the interactions, in a large population limit $$N \rightarrow \infty $$ . We build data-driven kernel estimators and establish oracle inequalities, following Lepski’s principle. Our results are based on a new Bernstein concentration inequality in McKean–Vlasov models for the empirical measure around its mean, possibly of independent interest. We obtain adaptive estimators over anisotropic Holder smoothness classes built upon the solution map of the Fokker–Planck equation, and prove their optimality in a minimax sense. In the specific case of the Vlasov model, we derive an estimator of the interaction potential and establish its consistency.

Financial incentives for smoking cessation in pregnancy: multicentre randomised controlled trial.

Abstract: Objective To evaluate the efficacy of financial incentives dependent on continuous smoking abstinence on smoking cessation and birth outcomes among pregnant smokers. Design Single blind, randomised controlled trial. Setting Financial Incentive for Smoking Cessation in Pregnancy (FISCP) trial in 18 maternity wards in France. Participants 460 pregnant smokers aged at least 18 years who smoked ≤5 cigarettes/day or ≤3 roll-your-own cigarettes/day and had a pregnancy gestation of Interventions Participants in the financial incentives group received a voucher equivalent to €20 (£17; $23), and further progressively increasing vouchers at each study visit if they remained abstinent. Participants in the control group received no financial incentive for abstinence. All participants received a €20 show-up fee at each of six visits. Main outcome measures The main outcome measure was continuous smoking abstinence from the first post-quit date visit to visit 6, before delivery. Secondary outcomes in the mothers were point prevalence abstinence, time to smoking relapse, withdrawal symptoms, blood pressure, and alcohol and cannabis use in past 30 days. Secondary outcomes in the babies were gestational age at birth, birth characteristics (birth weight, length, head circumference, Apgar score), and a poor neonatal outcome—a composite measure of transfer to the neonatal unit, congenital malformation, convulsions, or perinatal death. Results Mean age was 29 years. In the financial incentives and control groups, respectively, 137 (59%) and 148 (65%) were employed, 163 (71%) and 171 (75%) were in a relationship, and 41 (18%) and 31 (13%) were married. The participants had smoked a median of 60 cigarettes in the past seven days. The continuous abstinence rate was significantly higher in the financial incentives group (16%, 38/231) than control group (7%, 17/229): odds ratio 2.45 (95% confidence interval 1.34 to 4.49), P=0.004). The point prevalence abstinence rate was higher (4.61, 1.41 to 15.01, P=0.011), the median time to relapse was longer (visit 5 (interquartile range 3-6) and visit 4 (3-6), P Conclusions Financial incentives to reward smoking abstinence compared with no financial incentives were associated with an increased abstinence rate in pregnant smokers. Financial incentives dependent on smoking abstinence could be implemented as a safe and effective intervention to help pregnant smokers quit smoking. Trial registration ClinicalTrials.gov NCT02606227.

A conservative approach for online credit scoring

Abstract: This research is aimed at the case of credit scoring in risk management and presents a novel machine learning method to be used for the default prediction of high-risk branches or customers. This study uses the Kruskal-Wallis non-parametric statistic to form a conservative credit-scoring model and to study the impact on modeling performance on the benefit of the credit provider. The findings show that the new credit scoring methodology represents a reasonable coefficient of determination and a very low false-negative rate. It is computationally less expensive with high accuracy with around 18% improvement in Recall/Sensitivity. Because of the recent perspective of continued credit/behavior scoring, our study suggests using this credit score for non-traditional data sources for online loan providers to allow them to study and reveal changes in client behavior over time and choose the reliable unbanked customers, based on their application data. This is the first study that develops an online non-parametric credit scoring system, which is able to reselect effective features automatically for continued credit evaluation and weigh them out by their level of contribution with a good diagnostic ability.

Being a vet: the veterinary profession in social science research

Abstract: This article presents a review of the social science literature on the veterinary profession. It highlights the current debates on the profession. The texts discussed in this review mainly relate to the fields of history, sociology, political sciences and social geography, although multidisciplinary or management studies publications are sometimes referred to. This article analyses four major structuring dynamics: the sociodemographic evolutions that are currently taking place within the profession (1); the transformation of practices and knowledge in relation, on the one hand, to the increase in the number of pets (2) and, on the other hand, to the evolution of farming systems (3); and the ways public authorities govern veterinary public health (4).

Afraid of engagement? Towards an understanding of engagement in virtual communities of practice

Abstract: Virtual communities of practice (VCoPs) foster learning and knowledge sharing between employees. However, many virtual communities of practice fail due to the lack of engagement of collaborators. E...