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See detailTesting for association between RNA-Seq and high-dimensional data
Rauschenberger, Armin UL; Jonker, Marianne A.; van de Wiel, Mark A. et al

in BMC Bioinformatics (2016), 17

Background: Testing for association between RNA-Seq and other genomic data is challenging due to high variability of the former and high dimensionality of the latter. Results: Using the negative binomial ... [more ▼]

Background: Testing for association between RNA-Seq and other genomic data is challenging due to high variability of the former and high dimensionality of the latter. Results: Using the negative binomial distribution and a random-effects model, we develop an omnibus test that overcomes both difficulties. It may be conceptualised as a test of overall significance in regression analysis, where the response variable is overdispersed and the number of explanatory variables exceeds the sample size. Conclusions: The proposed test can detect genetic and epigenetic alterations that affect gene expression. It can examine complex regulatory mechanisms of gene expression. The R package globalSeq is available from Bioconductor. [less ▲]

Detailed reference viewed: 45 (1 UL)
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See detailTesting informed SIR based epidemiological model for COVID-19 in Luxembourg
Sauter, Thomas UL; Pires Pacheco, Maria Irene UL

in medRxiv (2020)

The interpretation of the number of COVID-19 cases and deaths in a country or region is strongly dependent on the number of performed tests. We developed a novel SIR based epidemiological model (SIVRT ... [more ▼]

The interpretation of the number of COVID-19 cases and deaths in a country or region is strongly dependent on the number of performed tests. We developed a novel SIR based epidemiological model (SIVRT) which allows the country-specific integration of testing information and other available data. The model thereby enables a dynamic inspection of the pandemic and allows estimating key figures, like the number of overall detected and undetected COVID-19 cases and the infection fatality rate. As proof of concept, the novel SIVRT model was used to simulate the first phase of the pandemic in Luxembourg. An overall number of infections of 13.000 and an infection fatality rate of 1,3 was estimated, which is in concordance with data from population-wide testing. Furthermore based on the data as of end of May 2020 and assuming a partial deconfinement, an increase of cases is predicted from mid of July 2020 on. This is consistent with the current observed rise and shows the predictive potential of the novel SIVRT model. [less ▲]

Detailed reference viewed: 40 (4 UL)
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See detailTesting Is More Desirable When It Is Adaptive and Still Desirable When Compared to Note-Taking
Heitmann, Svenja; Grund, Axel UL; Berthold, Kirsten et al

in FRONTIERS IN PSYCHOLOGY (2018), 9

Testing is a well-established desirable difficulty. Yet there are still some open issues regarding the benefits of testing that need to be addressed. First, the possibility to increase its benefits by ... [more ▼]

Testing is a well-established desirable difficulty. Yet there are still some open issues regarding the benefits of testing that need to be addressed. First, the possibility to increase its benefits by adapting the sequence of test questions to the learners' level of knowledge has scarcely been explored. In view of theories that emphasize the benefits of adapting learning tasks to learner knowledge, it is reasonable to assume that the common practice of providing all learners with the same test questions is not optimal. Second, it is an open question as to whether the testing effect prevails if stronger control conditions than the typical restudy condition are used. We addressed these issues in an experiment with N = 200 university students who were randomly assigned to (a) adaptive testing, (b) non-adaptive testing, or note-taking (c) without or (d) with focus guidance. In an initial study phase, all participants watched an e-lecture. Afterward, they processed its content according to their assigned conditions. One week later, all learners took a posttest. As main results, we found that adaptive testing yielded higher learning outcomes than non-adaptive testing. These benefits were mediated by the adaptive learners' higher testing performance and lower perceived cognitive demand during testing. Furthermore, we found that both testing groups outperformed the note-taking groups. Jointly, our results show that the benefits of testing can be enhanced by adapting the sequence of test questions to learners' knowledge and that testing can be more effective than note-taking. [less ▲]

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See detailTesting measurement Invariance in a CFA framework – State of the art
Sischka, Philipp UL

Poster (2017, March 31)

In recent years, several studies have stressed out the importance to guarantee the comparability of theoretical constructs (i.e. measurement invariance) in the compared units (e.g., groups or time points ... [more ▼]

In recent years, several studies have stressed out the importance to guarantee the comparability of theoretical constructs (i.e. measurement invariance) in the compared units (e.g., groups or time points) in order to conduct comparative analyses (e.g. Harkness, Van de Vijver, & Mohler, 2003; Meredith, 1993; Vandenberg, & Lance, 2000). If one does not test for measurement invariance (MI) or ignores lack of invariance, differences between groups in the latent constructs cannot be unambiguously attributed to ‘real’ differences or to differences in the measurement attributes. One approach to test for MI is in a confirmatory factor analysis (CFA) framework. In this framework, MI is usually tested with a series of model comparisons that define more and more stringent equality constraints. The presentation will be about new developments in the MI-CFA framework. Among other things, the presentation tries to answer the following questions: • Which scale setting method to use (marker variable, fixed factor or effect coding method) when testing for MI? • Should a top-down- or bottom-up-approach be used? • How to test MI with a large number of groups (>30)? • What are the possibilities to evaluate whether MI exists (e.g., statistical significance of the ∆² after Bonferroni adjustment, changes in approximate fit statistics, magnitude of difference between the parameter estimates)? • How to determine confidence intervals for fit indices? • Can MI be graphically analyzed? • How can be dealt with non-invariance? These questions will be tried to answered by an application to a real world dataset (N ~ 40.000), with a one-factor/five indicator model of a well-being scale tested in 35 groups. [less ▲]

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See detailTesting measurement invariance in a confirmatory factor analysis framework – State of the art
Sischka, Philipp UL

Scientific Conference (2017, August 31)

In recent years, several studies have stressed out the importance to guarantee the comparability of theoretical constructs (i.e. measurement invariance) in the compared units (e.g., groups or time points ... [more ▼]

In recent years, several studies have stressed out the importance to guarantee the comparability of theoretical constructs (i.e. measurement invariance) in the compared units (e.g., groups or time points) in order to conduct comparative analyses (e.g. Harkness, Van de Vijver, & Mohler, 2003; Meredith, 1993; Vandenberg, & Lance, 2000). If one does not test for measurement invariance (MI) or ignores lack of invariance, differences between groups in the latent constructs cannot be unambiguously attributed to ‘real’ differences or to differences in the measurement attributes. One approach to test for MI is in a confirmatory factor analysis (CFA) framework. The presentation will be about new developments in the MI-CFA framework. Among other things, the presentation tries to answer the following questions: • Which scale setting method to use (marker variable, fixed factor or effect coding method) when testing for MI? • Should a top-down- or bottom-up-approach be used? • How to test MI with a large number of groups (>30)? • What are the possibilities to evaluate whether MI exists (e.g., statistical significance of the change in chi-square after Bonferroni adjustment, changes in approximate fit statistics, magnitude of difference between the parameter estimates)? • How to determine confidence intervals for fit indices? • Can MI be graphically analyzed? • How can be dealt with non-invariance? These questions will be tried to answered by an application to a real world dataset (N ~ 40.000), with a one-factor/five indicator model of a well-being scale tested in 35 groups. [less ▲]

Detailed reference viewed: 27 (2 UL)
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See detailTESTING MUSIC READING WITH EYE TRACKING IN THREE EUROPEAN COUNTRIES
Buzas, Zsuzsa; Steklács, János; Sagrillo, Damien UL et al

in Max, Charles (Ed.) EAPRIL 2015 Proceedings (2016)

In our research we examined 10-14 years old students' music reading skills with eye tracking analysis in different music schools in Luxembourg, Germany and Hungary. Our aims were to explore certain music ... [more ▼]

In our research we examined 10-14 years old students' music reading skills with eye tracking analysis in different music schools in Luxembourg, Germany and Hungary. Our aims were to explore certain music reading strategies, reveal the characteristics of expert sight-readers and also to find text characteristics. During the examination students got six different musical examples (three for rythm reading, three for singing from Zoltán Kodály) that appeared on a computer's screen, and after one minute silent reading they performed them.The results suggest that the knowledge of musical patterns strongly influences not only the duration and accuration of a musical performance, but the fixation counts, and also gender differences were revealed. Our further aim is examining the relationship between the development of reading and music reading skills. [less ▲]

Detailed reference viewed: 135 (1 UL)
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See detailTesting music reading with eye tracking in three European countries textbooks
Buzás, Zsuzsa; Devosa, Iván; Maródi, Ágnes et al

Scientific Conference (2015, November 25)

In our research we examined 10-14 years old students' music reading skills with eye tracking analysis in different music schools in Luxembourg, Germany and Hungary. Our aims were to explore certain music ... [more ▼]

In our research we examined 10-14 years old students' music reading skills with eye tracking analysis in different music schools in Luxembourg, Germany and Hungary. Our aims were to explore certain music reading strategies, find possibilities of teaching them, reveal the characteristics of expert sight-reading strategy users and also to find gender differences. During the examination students got six different musical examples (3 for rythm reading, 3 for singing from Zoltán Kodály) that appeared on a computer's screen, and after one minute silent reading they performed them.The results suggest that the knowledge of musical patterns strongly influences not only the duration and accuration of a musical performance, but the fixation counts, and also several gender differences were revealed. Our further aim is examining the relationship between the development of reading and music reading skills. [less ▲]

Detailed reference viewed: 131 (5 UL)
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See detailTesting obligation policy enforcement using mutation analysis
Elrakaiby, Yehia UL; Mouelhi, Tejeddine UL; Le Traon, Yves UL

in Proceedings - IEEE 5th International Conference on Software Testing, Verification and Validation, ICST 2012 (2012)

The support of obligations with access control policies allows the expression of more sophisticated requirements such as usage control, availability and privacy. In order to enable the use of these ... [more ▼]

The support of obligations with access control policies allows the expression of more sophisticated requirements such as usage control, availability and privacy. In order to enable the use of these policies, it is crucial to ensure their correct enforcement and management in the system. For this reason, this paper introduces a set of mutation operators for obligation policies. The paper first identifies key elements in obligation policy management, then presents mutation operators which injects minimal errors which affect these aspects. Test cases are qualified w.r.t. their ability in detecting problems, simulated by mutation, in the interactions between policy management and the application code. The use of policy mutants as substitutes for real flaws enables a first investigation of testing obligation policies in a system. We validate our work by providing an implementation of the mutation process: the experiments conducted on a Java program provide insights for improving test selection. © 2012 IEEE. [less ▲]

Detailed reference viewed: 93 (0 UL)
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See detailTesting Obligation Policy Enforcement using Mutation Analysis
El Rakaiby, Yehia UL; Mouelhi, Tejeddine UL; Le Traon, Yves UL

in Proceedings of the 7th International Workshop on Mutation Analysis (associated to the Fifth International Conference on Software Testing, Verification, and Validation, ICST 2012) (2012)

The support of obligations with access control policies allows the expression of more sophisticated requirements such as usage control, availability and privacy. In order to enable the use of these ... [more ▼]

The support of obligations with access control policies allows the expression of more sophisticated requirements such as usage control, availability and privacy. In order to enable the use of these policies, it is crucial to ensure their correct enforcement and management in the system. For this reason, this paper introduces a set of mutation operators for obligation policies. The paper first identifies key elements in obligation policy management, then presents mutation operators which injects minimal errors which affect these aspects. Test cases are qualified w.r.t. their ability in detecting problems, simulated by mutation, in the interactions between policy management and the application code. The use of policy mutants as substitutes for real flaws enables a first investigation of testing obligation policies in a system. We validate our work by providing an implementation of the mutation process: the experiments conducted on a Java program provide insights for improving test selection. [less ▲]

Detailed reference viewed: 99 (0 UL)
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See detailTesting persistence of cohort effects in the epidemiology of suicide: an age-period-cohort hysteresis model
Chauvel, Louis UL; Leist, Anja UL; Ponomarenko, Valentina UL

in PLoS ONE (2016)

Birth cohort effects in suicide rates are well established, but to date there is no methodological approach or framework to test the temporal stability of these effects. We use the APC-Detrended (APCD ... [more ▼]

Birth cohort effects in suicide rates are well established, but to date there is no methodological approach or framework to test the temporal stability of these effects. We use the APC-Detrended (APCD) model to robustly estimate intensity of cohort effects identifying non-linear trends (or ‘detrended’ fluctuations) in suicide rates. The new APC-Hysteresis (APCH) model tests temporal stability of cohort effects. Analysing suicide rates in 25 WHO countries (periods 1970–74 to 2005–09; ages 20–24 to 70–79) with the APCD method, we find that country-specific birth cohort membership plays an important role in suicide rates. Among 25 countries, we detect 12 nations that show deep contrasts among cohort-specific suicide rates including Italy, Australia and the United States. The APCH method shows that cohort fluctuations are not stable across the life course but decline in Spain, France and Australia, whereas they remain stable in Italy, the United Kingdom and the Netherlands. We discuss the Spanish case with elevated suicide mortality of cohorts born 1965-1975 which declines with age, and the opposite case of the United States, where the identified cohort effects of those born around 1960 increase smoothly, but statistically significant across the life course. [less ▲]

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See detailTesting the discrimination hypothesis for female self employment migrants in the UK
Constantinidis, Christina UL; Fletcher, Denise Elaine UL; Joxhe, Majlinda UL

in IAFFE (Ed.) Books of Abstracts (2017, July 01)

We propose a comparative analysis of migrants in both sectors (employment and self-employment) exploring the gender earning discrimination hypothesis. Using individual micro data from the British ... [more ▼]

We propose a comparative analysis of migrants in both sectors (employment and self-employment) exploring the gender earning discrimination hypothesis. Using individual micro data from the British Household Panel Survey (1991-2008), we estimate wage equations for employed and self-employed migrants and find that, contrary to our expectations, the average earnings gap in self-employment is almost double compared to the employment sector. This finding reveals that self-employment leads migrant women to an even more precarious and vulnerable position in terms of financial means and economic power. In addition, we explore the determinants of these gaps using the econometric procedure of the decomposition (the Blinder-Oaxaca) model. We find that the variables that explain the gender gap in the employment sector are mostly observable individual characteristics like education or migration duration, confirming the human capital theory, whereas in the self-employment sector, this gap is more due to unobservable individual characteristics. Through our work, we show that including the gender perspective into migration analysis has implications for policy makers enabling them to evaluate these processes from a more social (rather than individualistic) dimension. [less ▲]

Detailed reference viewed: 149 (10 UL)
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See detailTesting the role of accountability in teachers’ school placement decisions: Findings from an experimental study
Glock, Sabine; Klapproth, Florian; Krolak-Schwerdt, Sabine UL et al

Scientific Conference (2012, June)

Detailed reference viewed: 17 (0 UL)
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See detailTesting the Untestable: Model Testing of Complex Software-Intensive Systems
Briand, Lionel UL; Nejati, Shiva UL; Sabetzadeh, Mehrdad UL et al

in Proceedings of the 38th International Conference on Software Engineering (ICSE 2016) Companion (2016, May)

Detailed reference viewed: 618 (50 UL)
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See detailTesting Vision-Based Control Systems Using Learnable Evolutionary Algorithms
Ben Abdessalem (helali), Raja UL; Nejati, Shiva UL; Briand, Lionel UL et al

in Proceedings of the 40th International Conference on Software Engineering (ICSE 2018) (2018)

Vision-based control systems are key enablers of many autonomous vehicular systems, including self-driving cars. Testing such systems is complicated by complex and multidimensional input spaces. We ... [more ▼]

Vision-based control systems are key enablers of many autonomous vehicular systems, including self-driving cars. Testing such systems is complicated by complex and multidimensional input spaces. We propose an automated testing algorithm that builds on learnable evolutionary algorithms. These algorithms rely on machine learning or a combination of machine learning and Darwinian genetic operators to guide the generation of new solutions (test scenarios in our context). Our approach combines multiobjective population-based search algorithms and decision tree classification models to achieve the following goals: First, classification models guide the search-based generation of tests faster towards critical test scenarios (i.e., test scenarios leading to failures). Second, search algorithms refine classification models so that the models can accurately characterize critical regions (i.e., the regions of a test input space that are likely to contain most critical test scenarios). Our evaluation performed on an industrial automotive vision-based control system shows that: (1) Our algorithm outperforms a baseline evolutionary search algorithm and generates 78% more distinct, critical test scenarios compared to the baseline algorithm. (2) Our algorithm accurately characterizes critical regions of the system under test, thus identifying the conditions that likely to lead to system failures. [less ▲]

Detailed reference viewed: 767 (169 UL)
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See detailTesting Voters' Understanding of a Security Mechanism Used in Verifiable Voting
Ryan, Peter UL; Schneider, Steve; Xia, Zhe et al

in 53 USENIX Journal of Election Technology and Systems (JETS) (2013), 1(1), 53-61

Proposals for a secure voting technology can involve new mechanisms or procedures designed to provide greater ballot secrecy or verifiability. These mechanisms may be justified on the technical level, but ... [more ▼]

Proposals for a secure voting technology can involve new mechanisms or procedures designed to provide greater ballot secrecy or verifiability. These mechanisms may be justified on the technical level, but researchers and voting officials must also consider how voters will understand these technical details, and how understanding may affect interaction with the voting systems. In the context of verifiable voting, there is an additional impetus for this consideration as voters are provided with an additional choice; whether or not to verify their ballot. It is possible that differences in voter understanding of the voting technology or verification mechanism may drive differences in voter behaviour; particularly at the point of verification. In the event that voter understanding partially explains voter decisions to verify their ballot, then variance in voter understanding will lead to predictable differences in the way voters interact with the voting technology. This paper describes an experiment designed to test voters’ understanding of the ‘split ballot’, a particular mechanism at the heart of the secure voting system Prˆet `a Voter, used to provide both vote secrecy and voter verifiability. We used a controlled laboratory experiment in which voter behaviour in the experiment is dependent on their understanding of the secrecy mechanism for ballots. We found that a two-thirds majority of the participants expressed a confident comprehension of the secrecy of their ballot; indicating an appropriate level of understanding. Among the remaining third of participants, most exhibited a behaviour indicating a comprehension of the security mechanism, but were less confident in their understanding. A small number did not comprehend the system. We discuss the implications of this finding for the deployment of such voting systems. [less ▲]

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See detailTestkonstruktion
Kemper, Christoph UL; Ziegler, M.; Krumm, S. et al

in Stemmler, G.; Margraf-Stiksrud, J. (Eds.) Lehrbuch Psychologische Diagnostik (2015)

Detailed reference viewed: 156 (8 UL)
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See detailTESTS AND ESTIMATION STRATEGIES ASSOCIATED TO SOME LOSS FUNCTIONS
Baraud, Yannick UL

E-print/Working paper (2020)

Detailed reference viewed: 75 (8 UL)
See detailTeststatistische Überprüfung der Impact of Event-Skala: Befunde zu Reliabilität und Stabilität.
Ferring, Dieter UL; Filipp, Sigrun-Heide

in Focus Diagnostica (1994), 40(4)

Detailed reference viewed: 212 (0 UL)
See detailTesttheoretische Analyse des Lese-Kompetenztests (4. Schulstufe) gemäß Bildungsstandards (Phase 1: 2006)
Hohensinn, Christine; Reif, Manuel; Gruber, Kathrin et al

Report (2007)

Detailed reference viewed: 19 (0 UL)
See detailTesttheoretische Analyse des Lese-Kompetenztests (4. Schulstufe) gemäß Bildungsstandards (Phase 2:2007)
Gruber, Kathrin; Reif, Manuel; Hohensinn, Christine et al

Report (2007)

Detailed reference viewed: 23 (0 UL)