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See detailBiofilm fermentation for the production of insect pathogenic fungi
Bawin, Thomas ULg; Francis, Frédéric ULg; Delvigne, Frank ULg

Poster (2016, July 27)

Currently, integrated pest management that aims to reduce the use of synthetic insecticides by considering all appropriate alternative methods, is promoted. In that context, insect pathogenic fungi could ... [more ▼]

Currently, integrated pest management that aims to reduce the use of synthetic insecticides by considering all appropriate alternative methods, is promoted. In that context, insect pathogenic fungi could be developed as biopesticides in two ways: spores but also metabolites that are recognized as virulence factors. Targeting adequate fermentation method is an important requirement to obtain fungal products (i.e. spores, enzymes and metabolites) of biotechnological interest. The 'Microbial Processes and Interactions' laboratory has developed an innovative fermentation technology (referred to as ‘biofilm fermentation’) involving the growth of fungal biomass on inert supports that are immersed in a liquid nutrient medium. Confining fungal biomass on immersed inert structures provides a hybrid production system aiming to keep a solid-state physiology for sporulation and secretion of metabolites while controlling fermentation parameters. This research project proposes to transfer this technology to culture insect pathogenic fungi, such as Metarhizium anisopliae, for the production of spores and insecticidal metabolites. Development stages include the qualitative and quantitative characterization of its impact on insecticidal products as well as scale-up to industrial level. [less ▲]

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See detailPolitiques mémorielles et contraintes juridiques
Grandjean, Geoffrey ULg

Conference (2016, July 27)

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See detailQuantitative characterization and calibration of salt water intrusion models with electrical resistivity tomography
Beaujean, Jean; Hermans, Thomas ULg; Vandenbohede, Alexander et al

Poster (2016, July 26)

Groundwater quality and coastal ecosystems in coastal areas are among the most vulnerable as they are threatened by excessive groundwater withdrawals, sea level rise and storm events potentially leading ... [more ▼]

Groundwater quality and coastal ecosystems in coastal areas are among the most vulnerable as they are threatened by excessive groundwater withdrawals, sea level rise and storm events potentially leading to salt water intrusions or infiltration into fresh water aquifers. The environmental protection and sustainable management of these groundwater resources often involves the development and calibration of a groundwater model subsequently used to forecast the total dissolved solid content (TDS). However, groundwater models are often built based on a limited number of sparse data due to borehole availability. Geophysical methods can provide spatially and temporally distributed data for hydrogeological modeling at relatively limited costs. In particular, electrical resistivity tomography (ERT) is very sensitive to the conductivity of pore water which is directly linked to the TDS content. The method is therefore well-suited for the monitoring of salt water intrusions. However, the inversion of ERT data involves a regularization process so that the resulting tomogram is only an estimate of the true resistivity distribution, suffering from smoothing and varying resolution. In many cases, the interpretation of ERT remains qualitative and skewed. In this contribution, we propose two different methods to improve the information content that can be extracted from ERT data. First, we show with a field example from Belgium how alternative regularization methods can be developed to integrate independent information into the inversion process of ERT. This enabled us to obtain a resistivity distribution much closer to the one observed in validation boreholes. Then, a site-specific petrophysical relationship is used to derive the TDS content of the aquifer from ERT tomograms. This can be directly used as input in the calibration process of a hydrogeological model. We also show how it is possible to counterbalance the effect of resolution loss with depth for surface ERT by filtering the results relative to their sensitivity. We show that this filtering is mandatory to use the ERT-derived information for calibrating a hydrogeological model. In a second example, we show how a fully coupled inversion approach can be used to directly invert geophysical data together with hydrogeological data for the calibration of hydrogeological models. At each iteration of the calibration, the simulated TDS content is transformed in a resistivity distribution using a parameterized petrophysical relationship and forward geophysical modeling yields the geophysical response. We show that this approach enables to better estimate the hydrogeological parameters of the simulated coastal aquifer than with an uncoupled approach if the conceptual model is sufficiently representative. With those two examples, we demonstrate the usefulness of ERT in the monitoring of salt water intrusions, both qualitatively to identify most vulnerable zones and quantitatively to estimate ERT-derived TDS contents or geophysical data and calibrate hydrogeological models. An innovative approach may consist in a conjunctive use of filtered geophysically-derived and geophysical data within the coupled hydrogeophysical inversion framework. Such an uncoupled-coupled approach based on a resolution threshold approach may offer a promising developing trend in hydrogeophysical inversion. [less ▲]

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See detailPolymeric Nanoparticles as siRNA Drug Delivery System for Cancer Therapy: The Long Road to Therapeutic Efficiency
Frère, Antoine ULg; Evrard, Brigitte ULg; Mottet, Denis ULg et al

in Holban, Alina Maria; Grumezescu, Alexandru (Eds.) Nanoarchitectonics for Smart Delivery and Drug Targeting (2016)

Polyplexes are nanoparticles composed of small-interfering RNA (siRNA) and natural or synthetic polymers. To meet the challenge of gene therapy and deliver siRNA into the cytoplasm of target cells ... [more ▼]

Polyplexes are nanoparticles composed of small-interfering RNA (siRNA) and natural or synthetic polymers. To meet the challenge of gene therapy and deliver siRNA into the cytoplasm of target cells, several barriers must be overcome. In this chapter, the main steps, from the formulation of polyplexes to the efficient release of the siRNA into the cytoplasm of cancer cells, are described, taking into account the different strategies used to overcome the obstacles linked to the formulation of this type of nanovector. To allow a parenteral administration of the nanocolloids, the polyplex production methods should result in identical, stable, and reproducible nanostructures. Charge interactions occur between the anionic siRNA and the cationic/amphiphilic polymer. Once in the blood circulation, polyplexes must keep their physical stability. The positively charged surface can cause aggregation of the nanoparticles with plasma proteins, as well as complement activation and recognition by the mononuclear phagocytic system, with a consequent reduction of their pharmacological activity. Polyethylene glycol (PEG) can be added on the surface of the nanovectors to confer “the stealth” properties and increase plasma half-life. Then, particles have to preferentially accumulate in the tumor tissue following an active or passive targeting. Endocytosis process enables the polyplex cellular uptake, but some strategies like “the proton sponge effect” have to be used to allow the escape of the nanovectors from the cellular endosomes. Once released into the cytoplasm, polymer and siRNA must dissociate for an effective degradation of the targeted mRNA, leading finally to a decrease of the corresponding protein. [less ▲]

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See detailImpacts of entomopathogenic fungi on biology and behaviour of the invasive Brown Marmorated Stink Bug (Hemiptera, Pentatomidae)
Fingu Mabola, Junior Corneille ULg; Serteyn, Laurent ULg; Bawin, Thomas ULg et al

Poster (2016, July 25)

Halyomorpha halys St˚al (Hemiptera, Pentatomidae) is an invasive stink bug coming from Eastern Asia. Besides causing important yields losses in orchards, crop and vegetable fields, it overwinters inside ... [more ▼]

Halyomorpha halys St˚al (Hemiptera, Pentatomidae) is an invasive stink bug coming from Eastern Asia. Besides causing important yields losses in orchards, crop and vegetable fields, it overwinters inside houses as agglomerates of dozens. In Europe, this Brown Marmorated Stink Bug (BMSB) was accidentally introduced in Switzerland in 2007 and has been later observed in surrounding countries (France, Italy, Germany). Based on the current US situation, we can reasonably fear that BMSB will have colonized most of Europe countries in less than a decade. If we already discern a few fungus strains that are efficient against BMSB, very little is known about their actual impact on the insect itself. So we investigated the in- fluence of a fungal infection on insect development parameters and behaviour. Olfactometry was settled to investigate the dispersion and aggregation trends, while electropenetography was used to assess the feeding behaviour. Our results will be discussed to present changes according to healthy/fungus-infected status, in relation to potential biological control for that pest. [less ▲]

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See detailApports phénoménologiques à l’étude de la relation au corps dans le jeu vidéo
Delbouille, Julie ULg

in Implications philosophiques (2016)

J’évite un obstacle. Je cours. Je saute. Alors que quelques notes de musique m’avertissent de l’échec de ce dernier mouvement, je vois mon corps chuter, happé par le vide au-delà de l’écran. Cette scène ... [more ▼]

J’évite un obstacle. Je cours. Je saute. Alors que quelques notes de musique m’avertissent de l’échec de ce dernier mouvement, je vois mon corps chuter, happé par le vide au-delà de l’écran. Cette scène, qui tout comme ses multiples variations s’inscrit en filigrane au cœur de nombreuses expériences vidéoludiques, soulève la question du rapport au corps dans le jeu vidéo. Dans le champ des Game et des Play Studies, nombreux sont les chercheurs qui se sont déjà emparés de l’interactivité comme objet d’étude, et d’une de ses modalités dans le jeu vidéo : l’avatar. Interface récurrente entre le joueur et l’univers vidéoludique, nous postulons que cette « enveloppe pilotable » constitue une porte d’entrée pour envisager la problématique corporelle dans le jeu vidéo. En effet, la fonction d’incarnation permise par l’avatar ajoute à la relation entre le corps et l’esprit du joueur une dimension nouvelle : celle du corps virtuel. Ce corps « autre », dont le joueur prend possession, constitue une des conditions de son « insertion » dans le monde du jeu. [less ▲]

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See detailDEM modeling of ball mills with experimental validation: influence of contact parameters on charge motion and power draw
Boemer, Dominik ULg; Ponthot, Jean-Philippe ULg

in Computational Particle Mechanics (2016)

Discrete element method simulations of a 1:5-scale laboratory ball mill are presented in this paper to study the influence of the contact parameters on the charge motion and the power draw. The position ... [more ▼]

Discrete element method simulations of a 1:5-scale laboratory ball mill are presented in this paper to study the influence of the contact parameters on the charge motion and the power draw. The position density limit is introduced as an efficient mathematical tool to describe and to compare the macroscopic charge motion in different scenarios, i.a. with different values of the contact parameters. While the charge motion and the power draw are relatively insensitive to the stiffness and the damping coefficient of the linear spring-slider-damper contact law, the coefficient of friction has a strong influence since it controls the sliding propensity of the charge. Based on the experimental calibration and validation by charge motion photographs and power draw measurements, the descriptive and predictive capabilities of the position density limit and the discrete element method are demonstrated, i.e. the real position of the charge is precisely delimited by the respective position density limit and the power draw can be predicted with an accuracy of about 5 %. [less ▲]

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See detailTweeting is not investing! But...
Choffray, Jean-Marie ULg

Diverse speeche and writing (2016)

So, that’s it! Hundreds of Tweets on The Art and Science of Investing to “show you the way”, to share my most recent observations on the behavior of the markets, and to illustrate some of the key ... [more ▼]

So, that’s it! Hundreds of Tweets on The Art and Science of Investing to “show you the way”, to share my most recent observations on the behavior of the markets, and to illustrate some of the key heuristics that I learned over the last twenty years. As, without any doubt, I am no Warren Buffett, feel free to disagree and develop you own “theory” of investing. Painful and solitary work... Success is at this price! And, based on what I did - and did not! - achieve, it shouldn’t be hard to do much better... That’s my wish for you! [less ▲]

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See detailSelf-inhibition of synthesis reduces antigen presentation of the alcelaphine herpesvirus 1-encoded latency-associated protein, aLANA
Sorel, Océane; Myster, Françoise; Vanderplasschen, Alain et al

Conference (2016, July 23)

Alcelalphine herpesvirus 1 (AlHV-1) persistently infects its natural host, the wildebeest, without inducing any clinical signs. However, cross-transmission to other ruminant species leads to the ... [more ▼]

Alcelalphine herpesvirus 1 (AlHV-1) persistently infects its natural host, the wildebeest, without inducing any clinical signs. However, cross-transmission to other ruminant species leads to the development of a deadly lymphoproliferative disease named malignant catarrhal fever (MCF). AlHV-1 ORF73 encodes the latency-associated nuclear antigen (LANA)-homolog protein termed aLANA. Similarly to other viral genome maintenance proteins encoded by gammaherpesviruses, aLANA has recently been shown to be essential for viral persistence and induction of MCF. Here we have investigated the self-inhibition of antigen presentation by aLANA and the potential role of such mechanism during the development of MCF. We showed that the GE-rich repeat domain of aLANA was sufficient to inhibit the presentation of an epitope linked to it. Though antigen presentation in absence of GE was dependent upon proteasomal degradation of aLANA, a lack of GE did not affect protein turnover. We further found that similarly to EBNA-1 GAr, aLANA GE downregulated protein self-synthesis. Likewise, such mechanism could be associated with reduced antigen presentation in vitro. In addition, in-frame insertion of GE repeat domain in a heterologous eGFP protein significantly down-regulated protein steady-state levels and self-antigen presentation. Next, we modified the AlHV-1 ORF73 gene sequence to reduce the purine bias in GE, without affecting the peptidic sequence. Such codon-modified aLANA GEm construct displayed increased antigen presentation. Finally, we generated an AlHV-1 recombinant strain expressing a GE-deficient aLANA protein and observed that viral growth was not affected in vitro by the absence of aLANA GE domain and MCF could be induced in rabbits irrespective of the expression of full-length aLANA or GE-deficient aLANA protein. [less ▲]

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See detailLa succession du prince-évêque de Liège dans les biens des ecclésiastiques
Lagasse, Benoît ULg

Conference (2016, July 23)

Explication du régime spécifique au diocèse de Liège de la succession du prince-évêque dans les biens des ecclésiastiques (distinction meubles/immeubles versus distinction biens propres/biens de l'Eglise ... [more ▼]

Explication du régime spécifique au diocèse de Liège de la succession du prince-évêque dans les biens des ecclésiastiques (distinction meubles/immeubles versus distinction biens propres/biens de l'Eglise en droit canonique général). [less ▲]

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See detailInvestir ou mourir, il faut choisir…
Choffray, Jean-Marie ULg

Book published by Amazon, Kindle Edition (2016)

Investir : c’est croire en l’avenir. C’est renoncer en partie au présent pour donner vie au futur. C’est tourner le dos aux « bouffeurs d’espoir » et à l’illusoire confort du statu quo. Enfin, et surtout ... [more ▼]

Investir : c’est croire en l’avenir. C’est renoncer en partie au présent pour donner vie au futur. C’est tourner le dos aux « bouffeurs d’espoir » et à l’illusoire confort du statu quo. Enfin, et surtout, c’est oser « oser » ! La distance séparant le discours public de la performance économique avérée suffit à démontrer l’incompréhension des mécanismes de création de richesse de ceux qui sont censés en avoir la maîtrise et/ou les mettre en œuvre. Il est peu de domaines où les illusions, et autres idées fausses, ont un succès tel qu’elles amènent à s’interroger sur le profit que d’aucuns pourraient en tirer… L’objet de cet ouvrage est de partager le fruit d’une réflexion menée sur le thème de l’investissement, forme proéminente et condition première de l’activité économique, au moment où certains s’interrogent sur son encadrement et cherchent à en limiter la liberté. Il aborde les bouleversements technologiques les plus significatifs ; l’art et la science d’investir avec Internet ; la recherche d’opportunités nouvelles ; et, se termine par quelques observations et souhaits quant à « l’état » du monde ! [less ▲]

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See detailIntegrating biological indicators in a monitoring network to improve soil quality diagnosis – a case study in Southern Belgium
Krüger, Inken ULg; Chartin, Caroline; van Wesemael, Bas et al

Conference (2016, July 21)

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See detailHCOOH distributions from IASI for 2008-2014: comparison with ground-based FTIR measurements and a global chemistry-transport model
Pommier, M.; Clerbaux, C.; Coheur, P.-F. et al

in Atmospheric Chemistry and Physics (2016), 16

Formic acid (HCOOH) is one of the most abundant volatile organic compounds in the atmosphere. It is a major contributor to rain acidity in remote areas. There are, however, large uncertainties on the ... [more ▼]

Formic acid (HCOOH) is one of the most abundant volatile organic compounds in the atmosphere. It is a major contributor to rain acidity in remote areas. There are, however, large uncertainties on the sources and sinks of HCOOH and therefore HCOOH is misrepresented by global chemistry-transport models. This work presents global distributions from 2008 to 2014 as derived from the measurements of the Infrared Atmospheric Sounding Interferometer (IASI), based on conversion factors between brightness temperature differences and representative retrieved total columns over seven regions: Northern Africa, southern Africa, Amazonia, Atlantic, Australia, Pacific, and Russia. The dependence of the measured HCOOH signal on the thermal contrast is taken into account in the conversion method. This conversion presents errors lower than 20 % for total columns ranging between 0.5 and 1 × 1016 molec/cm2 but reaches higher values, up to 78 %, for columns that are lower than 0.3 × 1016 molec/cm2. Signatures from biomass burning events are highlighted, such as in the Southern Hemisphere and in Russia, as well as biogenic emission sources, e.g., over the eastern USA. A comparison between 2008 and 2014 with ground-based Fourier transform infrared spectroscopy (FTIR) measurements obtained at four locations (Maido and Saint-Denis at La Réunion, Jungfraujoch, and Wollongong) is shown. Although IASI columns are found to correlate well with FTIR data, a large bias (> 100 %) is found over the two sites at La Réunion. A better agreement is found at Wollongong with a negligible bias. The comparison also highlights the difficulty of retrieving total columns from IASI measurements over mountainous regions such as Jungfraujoch. A comparison of the retrieved columns with the global chemistry-transport model IMAGESv2 is also presented, showing good representation of the seasonal and interannual cycles over America, Australia, Asia, and Siberia. A global model underestimation of the distribution and a misrepresentation of the seasonal cycle over India are also found. A small positive trend in the IASI columns is observed over Australia, Amazonia, and India over the 2008–2014 period (from 0.7 to 1.5 %/year), while a decrease of ∼ 0.8 %/year is measured over Siberia. [less ▲]

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See detailPublic Participation in Science and Technology and its Normative Context. The Participatory Turn’s Legacy and the European ‘Responsible Research and Innovation’ Emerging Framework
Macq, Hadrien ULg

Master's dissertation (2016)

Over the last two decades in Europe, science and technology’s unforeseen impacts led many STS scholars to plead for a ‘participatory turn’ in order to make our democracies more able to handle ... [more ▼]

Over the last two decades in Europe, science and technology’s unforeseen impacts led many STS scholars to plead for a ‘participatory turn’ in order to make our democracies more able to handle sociotechnical controversies. However, since the outset of this participatory turn, critiques sharing the common emphasize on the importance of taking into account the context in which public participation takes place have pointed to the risk of participation being either romanticized or instrumentalized. This thesis contributes to the critical scrutinizing of public participation in science and technology. By drawing on a set of qualitative data collection strategies and on a discourse analysis of collected materials, it investigates the normative context in which public participation is currently conceived and promoted at the European level and links it to historical perspectives in order to grasp the way in which the participatory turn’s legacy has been impacted. At it shows, far from being left opened-up, public participation is strongly closed-down by normative forces that lies in the context is which its promotion is currently taking place. As argued, public participation appears as instrumentalized in Horizon 2020 due to the increasing economization of policies and the steering of science and innovation toward tackling societal challenges. However, while acknowledging that these trends are characteristic of current developments, some longer ones are highlighted. Indeed, as this research suggests, the instrumentalization of public participation goes largely beyond the mere Horizon 2020. From the Sixth Framework Programme already, it appears that the normative context in which public participation in science and technology has been conceived and promoted has always tended to instrumentalized and to close down the deliberative governance of science. [less ▲]

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See detailLa logique de l'espace dans les stemmas de Lucien Tesnière
Mazziotta, Nicolas ULg

Conference (2016, July 19)

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See detailServitude et grandeur pédagogiques. Les nouvelles circonstances et exigences du métier de professeur de français langue étrangère.
Defays, Jean-Marc ULg

Scientific conference (2016, July 19)

Les circonstances ne sont guère favorables aux professeurs de français, ni aux professeurs de langues et de cultures d’une manière générale, qui traversent des temps aussi difficiles que cruciaux dans ... [more ▼]

Les circonstances ne sont guère favorables aux professeurs de français, ni aux professeurs de langues et de cultures d’une manière générale, qui traversent des temps aussi difficiles que cruciaux dans chacun de leur pays, chacune de leur institution et chacune de leur classe. Face à l’uniformisation linguistique et culturelle, aux restrictions budgétaires, à l’instrumentalisation de l’enseignement, c’est presque devenu un sacerdoce que de promouvoir la diversité non intéressée, les échanges non commerciaux, les valeurs non marchandes, bref l’humanisme. En ce qui concerne la langue française, partant les cultures francophones, le défi n’est pas seulement – par leur enseignement – de les maintenir vivantes et attrayantes dans des pays où elles sont étrangères ou secondes, mais aussi résistantes et entreprenantes dans les pays francophones où leur échappent des domaines d’activités aussi fondamentaux que l’économie, la diplomatie, la science, voire l’enseignement supérieur. Un défi encore plus important est de replacer la culture, les cultures, que la langue, que les langues, véhiculent, associent, enrichissent, au centre du vivre-ensemble sous peine de voir s’aggraver les replis et les conflits identitaires. C’est précisément en refusant de servir une conception étroite et stérile de la mondialisation qu’acquièrent leur grandeur les projets des professeurs de français dans le monde, de leurs associations, de la FIPF. [less ▲]

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See detailRecollection versus familiarity in normal aging and in mild cognitive impairment: Impact of test format.
Simon, Jessica ULg; Gilsoul, Jessica ULg; SALMON, Eric ULg et al

Poster (2016, July 18)

The aim of this study was to investigate the impact of test format on recollection and familiarity in normal aging and in MCI. Seventy young participants, 65 younger-old, 53 older-old, and 13 MCIs were ... [more ▼]

The aim of this study was to investigate the impact of test format on recollection and familiarity in normal aging and in MCI. Seventy young participants, 65 younger-old, 53 older-old, and 13 MCIs were presented with forced-choice and yes/no visual recognition memory tasks with the Remember/Know/Guess paradigm. The young people had better recognition performance than younger-old, who performed better than older-old and MCIs. Recollection and familiarity declined progressively in healthy aging. In MCI, recollection was more affected than familiarity, but patients demonstrated a more liberal use of familiarity. Finally, test format did not influence strongly the results. Young people used recollection more often in the forced-choice task compared to the yes/no task. [less ▲]

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See detailProbing single molecules with the AFM: Force, motion, dynamics, and function
Duwez, Anne-Sophie ULg

Conference (2016, July 18)

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See detailOn the use of ROC curves in DIF simulation studies
Magis, David ULg; Tuerlinckx, Francis

Conference (2016, July 14)

Simulation studies are often used to compare methods to detect differential item functioning (DIF). However, comparing the performance of such methods can become complicated when the identification of DIF ... [more ▼]

Simulation studies are often used to compare methods to detect differential item functioning (DIF). However, comparing the performance of such methods can become complicated when the identification of DIF items relies on statistics based on pre-defined significance level or on pre-established cutoff values. DIF methods based on conceptually different approaches may therefore become incomparable in terms of summary DIF statistics such as false alarm rate or hit rate. The purpose of this talk is to overcome this analytic issue by introducing receiver operating characteristic (ROC) curves in this context. ROC curves allow for global comparison of methods’ performances by computing pairs of (false alarm, hit) rates and representing them on a common scatter plot. Several summary ROC statistics can be considered for further analysis. The application of the ROC curve methodology, together with its limitation and possible extensions, is illustrated by a simple simulation study that compares three score-based DIF methods (Mantel-Haenszel, standardization and Delta plot). [less ▲]

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