Academic literature on the topic 'Quasi-experimental method'
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Journal articles on the topic "Quasi-experimental method"
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Darra, Maria, and Anastasia Papanthymou. "Research Designs and Methodologies of Studies in Student Self-Assessment: A Content Analysis." Journal of Studies in Education 9, no. 4 (October 7, 2019): 1. http://dx.doi.org/10.5296/jse.v9i4.15438.
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The purpose of this paper is to analyze the content of 33 empirical studies related to student self-assessment in primary and secondary education and have been published over the last decade (2009-2019) in 19 scientific journals classified in Scimago (only articles in journals with peer review system to assure their quality) in order to investigate: a) the research design (experimental, quasi-experimental, non-experimental), b) the research method (mixed method, quantitative method, qualitative method), c) the specific design (pretest-posttest etc.), d) the data collection method (questionnaire, interviews, etc.). According to the main findings most studies use non-experimental design, followed by experimental and quasi-experimental design. With regard to research methods quantitative method is used in all research designs, while qualitative and mixed method are used to a lesser degree and only in experimental and non-experimental design. Regarding the specific design, most experimental and quasi- experimental studies adopt a "pretest-posttest" design, while non-experimental studies follow mainly descriptive design. Finally, concerning the data collection methods, questionnaire is the most common method for all research designs, as opposed to other methods, such as interview or the combination of questionnaire and interview. Therefore, there is a need to investigate the issue of student self-assessment using experimental or quasi-experimental research design where the mixed methodological approach will be adopted and data collection will be carried out using various research tools such as the interview and the questionnaire in order to triangulate the results.
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Getmanov, Victor, Vladislav Chinkin, Roman Sidorov, Alexei Gvishiani, Mikhail Dobrovolsky, Anatoly Soloviev, Anna Dmitrieva, Anna Kovylyaeva, Nataliya Osetrova, and Igor Yashin. "Low-Pass Filtering Method for Poisson Data Time Series." Applied Sciences 11, no. 10 (May 15, 2021): 4524. http://dx.doi.org/10.3390/app11104524.
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Problems of digital processing of Poisson-distributed data time series from various counters of radiation particles, photons, slow neutrons etc. are relevant for experimental physics and measuring technology. A low-pass filtering method for normalized Poisson-distributed data time series is proposed. A digital quasi-Gaussian filter is designed, with a finite impulse response and non-negative weights. The quasi-Gaussian filter synthesis is implemented using the technology of stochastic global minimization and modification of the annealing simulation algorithm. The results of testing the filtering method and the quasi-Gaussian filter on model and experimental normalized Poisson data from the URAGAN muon hodoscope, that have confirmed their effectiveness, are presented.
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Reiser, Axel, and David G. Simmons. "A Quasi-experimental Method for Testing the Effectiveness of Ecolabel Promotion." Journal of Sustainable Tourism 13, no. 6 (November 15, 2005): 590–616. http://dx.doi.org/10.1080/09669580508668583.
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Ishiduka, Takumi, and Shinji Shinnaka. "Experimental Performance Evaluation of Quasi-Current-Error Method for AC Motor Drives." IEEJ Transactions on Industry Applications 135, no. 8 (2015): 882–83. http://dx.doi.org/10.1541/ieejias.135.882.
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Knudsen, Kati, Marieann Högman, Anders Larsson, and Ulrica Nilsson. "The Best Method to Predict Easy Intubation: A Quasi-Experimental Pilot Study." Journal of PeriAnesthesia Nursing 29, no. 4 (August 2014): 292–97. http://dx.doi.org/10.1016/j.jopan.2013.05.015.
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Dasen, Pierre R., Ramesh C. Mishra, and Jürg Wassmann. "Quasi-experimental research in culture sensitive psychology." Culture & Psychology 24, no. 3 (August 17, 2018): 327–42. http://dx.doi.org/10.1177/1354067x18779043.
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The research presented in this article follows up on several aspects of Gustav Jahoda’s long and fruitful career: (1) his early fieldwork on cognitive development in Africa, particularly in the area of spatial skills; (2) his interest in cross-cultural psychology as a research method; and (3) his insistence on bringing anthropology and psychology together. The topic of our research is the development of a so-called “geocentric” frame of spatial reference. This is a cognitive style, in which individuals describe and represent small-scale table-top space in terms of large-scale geographic dimensions. We explore the development with age of geocentric language and cognition, and the relationships between the two. We also explore the many environmental and socio-cultural variables that favor the use of this frame. We demonstrate how we untangled several of these variables by using a succession of within-society group comparisons, in several societies where a geocentric frame is in common usage (Bali, Indonesia, India, and Nepal). Our research program unfolds like a detective story, where one finding that is difficult to interpret because of several confounded variables leads to another quasi-experimental group comparison that suggests another hypothesis, which is then tested in a further session of field-work. In each case, we emphasize how important it was to have extensive linguistic and ethnographic knowledge before implementing psychological tests. The research design is not cross-cultural as such (we hardly ever perform comparisons between societies), but culturally sensitive within a series of societies; in other words, as Dasen and Jahoda (1986 , p. 413) defined it, “cross-cultural developmental psychology is not just comparative: essentially it is an outlook that takes culture seriously.”
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Sirotová, Mariana, Veronika Michvocíková, and Krzysztof Rubacha. "Quasi-experiment in the educational reality." Journal of Education Culture and Society 12, no. 1 (June 17, 2021): 189–201. http://dx.doi.org/10.15503/jecs2021.1.189.201.
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Aim. The main aim of the study is a presentation of the results of a quasi-experiment related to using a serious game in the preparation phase of supervised teaching practice as well as during its completion. Methods. The main method of the study is a quasi-experiment with the factor rotation technique. The method comprised two phases with two unequal groups of surveyed university students. In the first phase, the experimental influence was investigated in the first group and the second group served as the control group (to compare the results). In the second phase, the groups were switched around in the quasi-experiment; the control group became the experimental group and vice versa. Results. The presented study has a theoretical-empirical character. In the theoretical part, the characteristics of quasi-experiment and its use are briefly discussed. In the empirical part, the quasi-experiment is applied to the educational reality of future teachers. Supervised practice teaching is an important part of the university education of future teachers. Using a serious game therein is a positive element also when it comes to the development of students’ approach towards supervised teaching practice. Conclusion. Quasi-experiment is used as an experimental method for verification of examined reality. In the educational reality, its realisation is more difficult because it is a more demanding environment than a laboratory one. By realising the quasi-experiment, the theoretical supposition about the positive influence of serious games on the development of a university student’s personality can be confirmed.
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Lu, Zejian, Xiaoming Liu, Hai Wang, Xiaodong Chen, Yuan Yao, and Junsheng Yu. "Numerical and Experimental Verification of a 3D Quasi-Optical System." International Journal of Antennas and Propagation 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/595023.
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A modular and efficient Gaussian beam (GB) analysis method, incorporating frame-based Gabor transformation, GB reflection, and a 3D GB diffraction technique, was developed to analyze both the reflectors and frequency selective surface (FSS) in quasi-optical (QO) system. To validate this analysis method, a 3D dual-channel QO system operating at 183 and 325 GHz was designed and tested. The proposed QO system employs two-layer structure with a FSS of perforated hexagonal array transmitting the 325 GHz signal on the top layer while diverting the 183 GHz signal to the bottom layer. Measured results of the system demonstrate that the agreement can be achieved down to −30 dB signal level for both channels in the far field pattern. The discrepancy between the calculation and measurement is within 2 dB in the main beam region (2.5 times −3 dB beamwidth), verifying the effectiveness and accuracy of the proposed method.
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Smits, Michaël Willem Maria. "A quasi-experimental method for testing rural design support within a DRM framework." Smart and Sustainable Built Environment 8, no. 2 (May 7, 2019): 150–87. http://dx.doi.org/10.1108/sasbe-11-2017-0067.
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Purpose The purpose of this paper is to describe the quasi-experiment setting to test the formulated design support (developed in the author’s PhD research) within a design research methodology (DRM) framework. This support intends to help designers to consciously engage rural families within a development aid scenario and increase their self-reliance towards their built environment (housing). Design/methodology/approach This paper elaborates on the setting in which the design support was tested within a quasi-experiment. The literature section describes the challenges in design research and why the DRM is suitable for this type of empirical research. Findings Findings of the paper include a workable setting to organise and evaluate the impact of a design support within a DRM framework on a vulnerable rural community. Research limitations/implications The main limitation of the research lies in the study population. Due to financial and time constraints, only four teams could participate in the experiment conducted in rural Kenya. Social implications Further research will need to prove that the support works in comparable situations on the African continent. Originality/value The quasi-experiment setting within a DRM framework could benefit researchers in comparable empirical investigations.
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Campos, Eneida Rached, Djalma de Carvalho Moreira-Filho, and Marcos Tadeu Nolasco da Silva. "Improving patient care trajectories: an innovative quasi-experimental research method for health services." Ciência & Saúde Coletiva 23, no. 5 (May 2018): 1459–70. http://dx.doi.org/10.1590/1413-81232018235.08612016.
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Abstract Scores to predict treatment outcomes have earned a well-deserved place in healthcare practice. However, when used to help achieve excellence in the care of a given disease, scores should also take into account organizational and social aspects. This article aims to create scores to obtain key variables and its application in the management of care of a given disease. We present a method called Epidemiological Planning for Patient Care Trajectory (PELC) and its application in a research of HIV pediatric patients. This case study is presented by means of two studies. The first study deals with the development of the method PELC. The second is HIV Pediatric case-control study based on PELC method. HIV pediatric research - the first practical PELC application - found these four key variables to the individual quality level care trajectories: adherence to ART, attending at least one appointment with the otolaryngologist, attending at least one appointment with social services, and having missed one or more routine appointments. We believe PELC method can be used in researches about any kind of care trajectories, contributing to quality level advancements in health services, with emphasis on patient safety and equity in healthcare.
Dissertations / Theses on the topic "Quasi-experimental method"
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Wirén, Sacharias. "Working against anti-religious prejudice? : A mixed-method evaluation of ‘Together for Sweden’s storytelling method from a social psychology perspective." Thesis, Uppsala universitet, Teologiska institutionen, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-412802.
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The purpose of this study was to provide an initial evaluation of the effect of ‘Together for Sweden’s (TFS) storytelling method regarding anti-religious prejudice, based on a social identity perspective. Furthermore, the aim was to understand the possible self-perceived changes that the storytelling method contributes to regarding anti-religious prejudice. The study applied a mixed-method approach with a quasi-experimental design. The quantitative data collection consisted of a pre-and posttest with an experiment and control condition. The qualitative data collection consisted of semi-structured interviews with participants from the experiment condition. The quantitative results point to a positive self-perceived change in anti-religious prejudice. However, the change was small and not statistically significant in relation to the control condition. The qualitative find suggests that for some participants, the storytelling could provide an opportunity for a positive intergroup contact, counter-examples, counter-stereotypic information as well as addressing the categorization process through multiple and shared group memberships. The qualitative findings also point to a change regarding the view of religious people but not concerning the view of religion. This, together with a mixed response regarding affective shifts and a lack of intentional shifts, can help to explain the quantitative results. The findings of the study address the need to evaluate prejudice-reduction intervention in a school context as well as the need to test a social identity perspective outside a laboratory context. It also provided a first and tentative assessment of TFS’ storytelling method, which can contribute to a further adjustment of the method or future in-schools interventions.
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Louati, Haithem. "Experimental and numerical study of humid granular material : influence of liquid content in quasi-static regime." Thesis, Ecole nationale des Mines d'Albi-Carmaux, 2016. http://www.theses.fr/2016EMAC0008/document.
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Cette thèse est une étude expérimentale et numérique du comportement au cisaillement de milieu granulaire humide sous l’effet de la quantité de liquide introduite et la contrainte normale appliquée. Les expériences ont été faites sur une cellule de cisaillement annulaire, pour une large gamme de contraintes appliquées allant de presque 0.3 kPa à 12 kPa. Les résultats donnent la variation de la contrainte de cisaillement en régime stationnaire en fonction de la contrainte normale pour une large variation de la quantité de liquide. Le liquide dans le milieu granulaire va de ponts liquides formés au point de contact jusqu’au remplissage totale de l'espace entre les grains. L’effet de liquide sur la résistance au cisaillement et la porosité de milieu granulaire a été analysé. Différents régimes du comportement de milieu granulaire humide ont été identifiés. Afin d’acquérir une compréhension microscopique du comportement au cisaillement de milieu granulaire sec et partiellement humide, la méthode des éléments discrets (DEM) a été utilisée. Des billes de verre de grande taille (2 mm de diamètre) ont été utilisées pour réduire le temps de simulation et faciliter la caractérisation à l’échelle de particule. Une première partie a été consacrée à l’étude de l’effet des propriétés microscopiques de particule (Module de Young et la friction de glissement) sur les propriétés macroscopiques de milieu granulaire sec et humide (le nombre de coordination, la porosité, le ratio de contraintes et la vitesse de particules). Une deuxième partie a été concernée par l’étude du comportement au cisaillement de milieu granulaire humide pour différentes fractions de liquide et différentes contraintes normales appliquées. En particulier, les forces capillaires et le nombre de ponts liquide ont été quantitativement analysésWe study experimentally and numerically the shear behaviour of wet granular material. We investigate the effect of the liquid content and the applied normal stresses to this behaviour. An annular shear cell was used to carry out the experiments, for a large range of applied normal stress from about 0.3 kPa to 12 kPa. The results give the variation of the shear stress at steady-state as a function of the normal stress for a wide range of liquid fraction. The incorporated liquid goes from forming bridges at the contact point to completely filling the space between grains. The shear resistance and the voidage fraction variations with the liquid fraction were analysed. Depending on the applied normal stress and the liquid fraction, different regimes of the shear resistance were identified. The discrete element method (DEM) was used to gain a microscopic understanding of the shear behaviour of dry and partially wet granular material in the shear cell. Large size glass beads were used to speed up the computational time and to facilitate characterisation at the particle scale. First, the influence of the microscopic properties of the particle (The Young’s modulus and the sliding friction) on the macroscopic properties of dry and wet granular materials (the coordination number, the voidage fraction, the shear ratio and the velocity of particles) was investigated. Secondly, the shear behaviour of the partially wet granular material for different liquid fractions and normal stresses was studied. The capillary forces and the number of liquid bridges were quantitatively analysed
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Zobec, Helena, and helena zobec@canberra edu au. "An investigation of library literacy levels of flexible learners at the Canberra Institute of Technology: a pilot study." University of Canberra. Information Management & Tourism, 1998. http://erl.canberra.edu.au./public/adt-AUC20050809.143304.
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The present study attempted to measure library literacy levels of open or flexible
learners at the Canberra Institute of Technology (CIT) during the 1995 academic year,
and to investigate to what extent the information skills component of TAFE open
learning modules influence adult learners' library literacy levels.
To address these issues, a quasi-experimental research methodology was used to
measure library literacy levels at the beginning and, again, on or near course
completion to ascertain whether any change had occurred, through the administration
of a questionnaire. A number of participants were then interviewed to further validate
the responses fiom the questionnaires.
The study attempted to show that though courses claim to address key competencies
in a vocational education and training environment, one component of the key
competencies, the ability to collect, analyse and organise information, was not being
met. That one component was the ability to locate (or collect) information.
No strong correlations resulted fiom the library literacy levels measured and the
degree to which the key competency was addressed within course modules. No
statistical measures were possible due to the small sample population that eventuated,
though it was almost half the original targeted population. No real gain was achieved
in library literacy levels between the pretest and posttest stages of the research for
either the Experimental or Control groups. Though a highly suitable research
methodology, the quasi-experimental research design did have some limitations in this
piece of research. The CIT flexible learning environment at the time of the study
contributed to the limitations of the study.
However, a number of recommendations were made on the basis of the research
results, advocating some strategies that might be implemented to improve the library
literacy levels of learners undertaking open or flexible delivery courses within CIT,
and suggestions to change the research environment to avoid many of the problems
experienced.
The CIT pilot study was the first known formally documented study of library literacy
levels in an Australian TAFE environment of its kind. The study reflects the literature
published at the time of the study. At that time, the research in this field was minimal.
Many publications and research have emerged since 1995 when this study was
conducted, indicating this is an area of great interest.
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Miranda, Montero Juan Jose. "Essays on Experimental and Quasi-Experimental Policy Design and Evaluation." Digital Archive @ GSU, 2012. http://digitalarchive.gsu.edu/econ_diss/86.
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This dissertation comprises two essays. The unifying theme is the evaluation of non-pecuniary (information or norm based messages) conservation programs. These types of policies are widely applied in developing and developed countries to promote conservation, however, their empirical evidence and their effectiveness are not well documented. Each chapter examines some methodological facets of the heterogeneity of non-pecuniary conservation programs and the reliability of non-experimental methods (program evaluation and econometric techniques) to evaluate treatment effects in the context of non-pecuniary conservation programs.
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Stoeffler, Quentin. "Three Essays on Poverty in Sub-Saharan Africa: Multidimensional Poverty Change in Zimbabwe; Long-Term Impact of Cash Transfers in Niger; and Targeting Efficiency of Social Protection Programs in Cameroon." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/50444.
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This dissertation focuses on identifying the poor in Sub-Saharan Africa (SSA) and the potential of social assistance programs to address their condition. Each essay is related to one particular key step of the poverty alleviation agenda: poverty definition and measurement in Zimbabwe; targeting poor households in Cameroon; and impact evaluation of anti-poverty interventions in Niger.
The first essay explores changes in poverty across multiple dimensions in a period of dramatic economic crisis and recovery in Zimbabwe. The essay analyzes changes in household well-being between 2001, 2007 and 2011/12, using an Alkire-Foster multidimensional poverty index. Results indicate a large increase in multidimensional poverty across between 2001 and 2007, followed by a (smaller) decrease in poverty between 2007 and 2011/12 (recovery period after the hyperinflation peak in 2008). However, decomposition of the index shows significantly different trends in poverty dimensions over time, as for instance health related dimensions continued to deteriorate after 2007.
The second essay contributes to the policy debate on targeting by studying the ex-post efficiency of two targeting mechanisms employed in a cash transfer project in rural Cameroon: Proxy Means Testing (PMT) and community targeting. Results show a poor performance of community targeting in selecting households with low per capita consumption, compared to PMT targeting—whose errors remain high nonetheless. Communities tend to select small, isolated households with low physical and human capital, regardless of their actual consumption level, but produce variable outcomes. Overall results suggest that a higher coverage contributes to reducing targeting errors, and that better guidance should be provided to communities if the policy objective is to select low per capita consumption individuals.
The third essay investigate whether cash transfers induce investments in assets and productive activities that survive the termination of program payments using data from an unconditional cash transfer project in Niger 18 months after its termination. Based on quasi-experimental methods, results indicate that local saving/credit systems (tontines) participation and livestock ownership significantly increased among project participants. There is also evidence of improvement in private assets, micro-enterprises and agriculture. The findings imply that cash transfer programs can have long-term sustainable impacts in rural SSA.Ph. D.
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Watanabe, Emerson Ferrell. "A Quasi-Experimental Study of the Effect of Experience Staging Techniques on Engagement." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/7555.
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The purpose of this study is to examine the effect of experience staging techniques (personalization through co-creation and multisensory stimuli) on engagement level. This study also explores the possible contribution of experience staging techniques as practical tools that recreation professionals can use to better engage participants in recreation activities and events. A 2-way univariate ANOVA revealed no significant relationship between the use of co-creative and multisensory stimulating techniques and engagement levels in participants (F (3,200) = .263, p = .826, partial η2 = .004). Practical applications for recreation professionals and further research opportunities are discussed.
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Garabedian, Laura Faden. "Quasi-Experimental Health Policy Research: Evaluation of Universal Health Insurance and Methods for Comparative Effectiveness Research." Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:10764.
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This dissertation consists of two empirical papers and one methods paper. The first two papers use quasi-experimental methods to evaluate the impact of universal health insurance reform in Massachusetts (MA) and Thailand and the third paper evaluates the validity of a quasi-experimental method used in comparative effectiveness research (CER).
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Bristor, Valerie Jayne. "A quasi-experimental comparison of the test-study and study-test methods in fourth grade spelling." Virtual Press, 1988. http://liblink.bsu.edu/uhtbin/catkey/536295.
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The purpose of this study was to compare two methods of spelling instruction, the test-study method and study-test method, with the spelling achievement of selected fourth grade students. The effects of gender and spelling ability level on the spelling method were also studied. The participants were 80 fourth grade students from four intact classrooms in two elementary schools in a small suburban midwestern school district.Third grade standardized test scores were collected from students' permanent record cards and used for grouping students into spelling ability levels. A Spelling Criterion-Referenced Test was used as a pretest (covariate) and a posttest (dependent variable). An analysis of covariance was used to test three null hypotheses at the .05 level of significance. The three null hypotheses were not rejected. The following results were suggested:1. Both fourth grade boys and girls achieve equally well in spelling whether they use the test-study method or the study-test method of spelling instruction.2. Fourth grade students achieve equally well in spelling whether they use the test-study method or the study-test method of spelling instruction.3. Fourth grade girls and boys achieve equally well in spelling.Teachers should consider integrating spelling into all areas of the language arts by supplementing the spelling textbook with words the children are using in their writing.Department of Elementary Education
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Zhang, Tianyu. "Problème inverse statistique multi-échelle pour l'identification des champs aléatoires de propriétés élastiques." Thesis, Paris Est, 2019. http://www.theses.fr/2019PESC2068.
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Dans le cadre de la théorie de l'élasticité linéaire, la modélisation et simulation numérique du comportement mécanique des matériaux hétérogènes à microstructure aléatoire complexe soulèvent de nombreux défis scientifiques à différentes échelles. Bien qu'à l'échelle macroscopique, ces matériaux soient souvent modélisés comme des milieux homogènes et déterministes, ils sont non seulement hétérogènes et aléatoires à l'échelle microscopique, mais ils ne peuvent généralement pas non plus être explicitement décrits par les propriétés morphologiques et mécaniques locales de leurs constituants. Par conséquent, une échelle mésoscopique est introduite entre l'échelle macroscopique et l'échelle mésoscopique, pour laquelle les propriétés mécaniques d'un tel milieu élastique linéaire aléatoire sont décrites par un modèle stochastique prior non-gaussien paramétré par un nombre faible ou modéré d'hyperparamètres inconnus. Afin d'identifier ces hyperparamètres, une méthodologie innovante a été récemment proposée en résolvant un problème statistique inverse multi-échelle en utilisant uniquement des données expérimentales partielles et limitées aux deux échelles macroscopique et mésoscopique. Celui-ci a été formulé comme un problème d'optimisation multi-objectif qui consiste à minimiser une fonction-coût multi-objectif (à valeurs vectorielles) définie par trois indicateurs numériques correspondant à des fonctions-coût mono-objectif (à valeurs scalaires) permettant de quantifier et minimiser des distances entre les données expérimentales multi-échelles mesurées simultanément aux deux échelles macroscopique et mésoscopique sur un seul échantillon soumis à un essai statique, et les solutions des modèles numériques déterministe et stochastique utilisés pour simuler la configuration expérimentale multi-échelle sous incertitudes. Ce travail de recherche vise à contribuer à l'amélioration de la méthodologie d'identification inverse statistique multi-échelle en terme de coût de calcul, de précision et de robustesse en introduisant (i) une fonction-coût mono-objectif (indicateur numérique) supplémentaire à l'échelle mésoscopique quantifiant la distance entre la(les) longueur(s) de corrélation spatiale des champs expérimentaux mesurés et celle(s) des champs numériques calculés, afin que chaque hyperparamètre du modèle stochastique prior ait sa propre fonction-coût mono-objectif dédiée, permettant ainsi d'éviter d'avoir recours à l'algorithme d'optimisation global (algorithme génétique) utilisé précédemment et de le remplacer par un algorithme plus performant en terme d'efficacité numérique, tel qu'un algorithme itératif de type point fixe, pour résoudre le problème d'optimisation multi-objectif avec un coût de calcul plus faible, et (ii) une représentation stochastique ad hoc des hyperparamètres impliqués dans le modèle stochastique prior du champ d'élasticité aléatoire à l'échelle mésoscopique en les modélisant comme des variables aléatoires, pour lesquelles les distributions de probabilité peuvent être construites en utilisant le principe du maximum d'entropie sous un ensemble de contraintes définies par les informations objectives et disponibles, et dont les hyperparamètres peuvent être déterminés à l'aide de la méthode d'estimation du maximum de vraisemblance avec les données disponibles, afin d'améliorer à la fois la robustesse et la précision de la méthode d'identification inverse du modèle stochastique prior. En parallèle, nous proposons également de résoudre le problème d'optimisation multi-objectif en utilisant l’apprentissage automatique par des réseaux de neurones artificiels. Finalement, la méthodologie améliorée est tout d'abord validée sur un matériau virtuel fictif dans le cadre de l'élasticité linéaire en 2D contraintes planes et 3D, puis illustrée sur un matériau biologique hétérogène réel (os cortical de bœuf) en élasticité linéaire 2D contraintes planesWithin the framework of linear elasticity theory, the numerical modeling and simulation of the mechanical behavior of heterogeneous materials with complex random microstructure give rise to many scientific challenges at different scales. Despite that at macroscale such materials are usually modeled as homogeneous and deterministic elastic media, they are not only heterogeneous and random at microscale, but they often also cannot be properly described by the local morphological and mechanical properties of their constituents. Consequently, a mesoscale is introduced between macroscale and microscale, for which the mechanical properties of such a random linear elastic medium are represented by a prior non-Gaussian stochastic model parameterized by a small or moderate number of unknown hyperparameters. In order to identify these hyperparameters, an innovative methodology has been recently proposed by solving a multiscale statistical inverse problem using only partial and limited experimental data at both macroscale and mesoscale. It has been formulated as a multi-objective optimization problem which consists in minimizing a (vector-valued) multi-objective cost function defined by three numerical indicators corresponding to (scalar-valued) single-objective cost functions for quantifying and minimizing distances between multiscale experimental data measured simultaneously at both macroscale and mesoscale on a single specimen subjected to a static test, and the numerical solutions of deterministic and stochastic computational models used for simulating the multiscale experimental test configuration under uncertainties. This research work aims at contributing to the improvement of the multiscale statistical inverse identification method in terms of computational efficiency, accuracy and robustness by introducing (i) an additional mesoscopic numerical indicator allowing the distance between the spatial correlation length(s) of the measured experimental fields and the one(s) of the computed numerical fields to be quantified at mesoscale, so that each hyperparameter of the prior stochastic model has its own dedicated single-objective cost-function, thus allowing the time-consuming global optimization algorithm (genetic algorithm) to be avoided and replaced with a more efficient algorithm, such as the fixed-point iterative algorithm, for solving the underlying multi-objective optimization problem with a lower computational cost, and (ii) an ad hoc stochastic representation of the hyperparameters involved in the prior stochastic model of the random elasticity field at mesoscale by modeling them as random variables, for which the probability distributions can be constructed by using the maximum entropy principle under a set of constraints defined by the available and objective information, and whose hyperparameters can be determined using the maximum likelihood estimation method with the available data, in order to enhance both the robustness and accuracy of the statistical inverse identification method of the prior stochastic model. Meanwhile, we propose as well to solve the multi-objective optimization problem by using machine learning based on artificial neural networks. Finally, the improved methodology is first validated on a fictitious virtual material within the framework of 2D plane stress and 3D linear elasticity theory, and then illustrated on a real heterogenous biological material (beef cortical bone) in 2D plane stress linear elasticity
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Levi, Altstaedter Laura. "Writing Instruction in Foreign Language Courses: Multiple Perspectives on the Impact of Peer Feedback on Students’ Writing Proficiency." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/28384.
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Grounded in sociocultural theory, peer feedback can help students engage in interaction and negotiation of meaning, which serve as a basis for the construction of knowledge (Vygotsky, 1978). It can also contribute to the development of self-regulation, as well as of reflection on one's own learning (Doolittle & Hicks, 2003). Its strategic incorporation into foreign language instruction can help students use the language they are in the process of acquiring to mediate language acquisition (Shrum & Glisan, 2005).
Research shows that peer feedback can help students develop and advance their Zone of Proximal Development through their engagement in collaborative interaction with their peers (De Guerrero & Villamil, 1994, 2000; Donato, 2004; Lantolf, 2004; Lantolf & Thorne, 2006; Liu & Hansen, 2005). Peer feedback can also help students improve their writing proficiency, including organization of their texts and awareness of the mechanics of the language necessary for successful communication of the intended message (Kinsler, 1990; Hu, 2005; Williams, 2005).
Framed within a sociocultural perspective on foreign language learning and development, and following a manuscript approach, this dissertation consists of a series of studies that aim to explore: (a) whether participation in a peer feedback experience has a positive impact on students’ foreign language writing proficiency; (b) whether guidelines plus training in how to provide meaningful feedback have a different impact on students’ foreign language writing proficiency than guidelines alone; (c) around what themes students focus the feedback they provide to their peers; and (d) what students’ perceptions of the peer feedback experience are.
The results of the first the study, which consisted of a pre-test post-test quasi-experimental design, showed that students significantly improved their writing proficiency after participating in a peer feedback experience, regardless of training. Further the results of this study indicated that, on average, trained and untrained students provided written peer feedback focused mainly on global aspects rather than local aspects. The results of the second study, which consisted of a mixed methods approach, showed that, on average, students had high perceptions of the peer feedback experience and that they perceived that their partner's feedback had helped them improve the global aspects of their composition more than the local aspects. Students expressed that what they liked the most about the experience was getting a different perspective on their writing, and what they liked the least was that they felt they were not proficient enough in the foreign language to provide meaningful feedback to their peers.Ph. D.
Books on the topic "Quasi-experimental method"
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Rosenbaum, Paul R. Observational studies. New York: Springer-Verlag, 1995.
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Observational studies. 2nd ed. New York: Springer, 2002.
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Miksza, Peter, and Kenneth Elpus. Advances in Quasi-experimental Methods. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780199391905.003.0015.
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Although the primacy of the randomized experiment is often thought of as sacrosanct, in education research—and in music education research in particular—random assignment is often unachievable, unethical, or undesirable for one or more of many potential reasons. Methodologists have developed quasi-experimental research methods that attempt to achieve results that approximate the highly trustworthy results obtained from a randomized experiment. This chapter details two newer methods for quasi-experimental research that have become quite common in the broader field of education but have not yet become frequently employed within the field of music education research. These two methods are regression discontinuity designs and the use of propensity scores for the equating of nonequivalent groups.
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Miksza, Peter, and Kenneth Elpus. Causation and Causal Claims. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780199391905.003.0007.
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This chapter explores the philosophy of science surrounding warrants for causal claims, how researchers can use quantitative data to create causal knowledge, and how to evaluate the validity of causal knowledge generated through research. In music education, carefully answered causal questions can provide insights that improve both teaching and learning in music at all levels and in all contexts. In this chapter, details are provided on the kinds of experimental and quasi-experimental research designs most commonly employed for causal research, the challenges that researchers using these methods often face, and specific threats to validity that commonly occur in those designs.
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Gugerty, Mary Kay, and Dean Karlan. The CART Principles for Impact Evaluation. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780199366088.003.0006.
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The CART principles are essential for designing a right-fit impact evaluation. This chapter explains what it means to conduct credible, actionable, responsible, and transportable impact evaluation. To ensure that impact evaluations follow the CART principles, organizations ought to strive for bias-free data collection and analysis. Bias (systematic error that favors one measure over another) may come from the way data are collected (question wording influences responses), or the way they are analyzed (e.g., influence of external factors or how people are selected into programs). In many cases, an randomizied control trial (RCT) helps generate a credible impact evaluation. In the simplest version of an RCT, individuals are randomly assigned to treatment and control groups. However, in special circumstances, other quasi-experimental evaluation methods can be successful. Actionable impact evaluation requires that organizations commit to learn from the undertaking and act on the results, even if they are disappointing. Organizations can make sure an evaluation is responsible by weighing how much it costs relative to its expected benefits. This chapter also addresses common criticisms about RCTs and identifies some strategies for reducing their cost. Finally, the chapter explains that the transportable principle mandates that evaluations produce useful evidence for others.
Book chapters on the topic "Quasi-experimental method"
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Hamelin, P., A. Gabor, T. Q. Bach, and A. Si Larbi. "Optimization of Quasi-isotropic Formulation of Fiber-Cement Laminates: Polar Method and Experimental Validation." In High Performance Fiber Reinforced Cement Composites 6, 471–78. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-2436-5_57.
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Barrio Minton, Casey A. "Quasi-Experimental Methods." In Making Research Relevant, 109–24. New York, NY : Routledge, 2018.: Routledge, 2018. http://dx.doi.org/10.4324/9781315179353-8.
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Patten, Mildred L., and Michelle Newhart. "Quasi-Experimental Designs." In Understanding Research Methods, 195–97. Tenth edition. | New York, NY : Routledge, 2017.: Routledge, 2017. http://dx.doi.org/10.4324/9781315213033-63.
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Levesque, Roger J. R. "Experimental and Quasi-Experimental Methods." In Encyclopedia of Adolescence, 900–902. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-1695-2_655.
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Levesque, Roger J. R. "Experimental and Quasi-Experimental Methods." In Encyclopedia of Adolescence, 1271–72. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-33228-4_655.
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Yeaton, William H. "Experimental and quasi-experimental designs." In Advanced Research Methods for Applied Psychology, 107–23. Abingdon, Oxon; New York, NY: Routledge, [2018]: Routledge, 2018. http://dx.doi.org/10.4324/9781315517971-12.
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Rogers, John, and Andrea Révész. "Experimental and quasi-experimental designs." In The Routledge Handbook of Research Methods in Applied Linguistics, 133–43. New York : Taylor and Francis, 2020. | Series: Routledge handbooks in applied linguistics: Routledge, 2019. http://dx.doi.org/10.4324/9780367824471-12.
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Tartaro, Christine. "Causation, Experimental, and Quasi-Experimental Designs." In Research Methods for Criminal Justice and Criminology, 53–115. New York, NY : Routledge, 2021.: Routledge, 2021. http://dx.doi.org/10.4324/9781003051763-5.
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Thyer, Bruce A. "Pre-Experimental and Quasi-Experimental Research Designs." In The Handbook of Social Work Research Methods, 183–204. 1 Oliver's Yard, 55 City Road London EC1Y 1SP: SAGE Publications, Inc., 2010. http://dx.doi.org/10.4135/9781544364902.n11.
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Kraska, Peter B., John J. Brent, and W. Lawrence Neuman. "Experimental and Quasi‑Experimental Crime and Justice Research." In Criminal Justice and Criminology Research Methods, 195–225. 3rd Edition. | New York: Routledge, 2021. | Revised edition of the authors’ Criminal justice and criminology research methods, c2012.: Routledge, 2020. http://dx.doi.org/10.4324/9780429026256-7.
Full textConference papers on the topic "Quasi-experimental method"
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Hussein, Bassam A. "Quasi-experimental method to identify the impact of ambiguity and urgency on project participants in the early project phase." In 2011 IEEE 6th International Conference on Intelligent Data Acquisition and Advanced Computing Systems: Technology and Applications (IDAACS). IEEE, 2011. http://dx.doi.org/10.1109/idaacs.2011.6072901.
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Nili-Ahmadabadi, Mahdi, Mohammad Durali, and Ali Hajilouy-Benisi. "A Novel Quasi 3-D Design Method for Centrifugal Compressor Meridional Plane." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-23341.
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This paper is concerned with a quasi-3D design method for centrifugal compressor impeller in the meridional plane. The method links up a novel inverse design algorithm, called Ball-Spine Algorithm (BSA), and a quasi-3D analysis code. The Euler equation is solved on the meridional plane for a numerical domain of which some unknown boundaries (hub and shroud) are iteratively modified under the BSA until a prescribed pressure distribution is reached. In BSA, the unknown walls are composed of a set of virtual balls that move freely along the specified directions called spines. The difference between target and current pressure distribution causes to deform flexible boundary at each modification step. In order to validate the quasi-3D analysis code, an existing compressor is investigated by some experiments in which several static pressure points on the shroud, the flow parameters at the compressor inlet and outlet are measured. Comparison of the quasi-3D analysis results with experimental results shows good agreement. Also, a full 3D Navier-Stokes code is used to analyze the existing and designed compressor numerically. The results show that the momentum decrease near the shroud wall in the existing compressor is removed by hub-shroud modification resulting an improvement in performance by 0.6 percent.
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Zarei Mahmoudabadi, M., M. Sadighi, and A. Eyvazian. "Theoretical and Experimental Crushing Analysis of Metal Square Honeycombs Under Quasi-Static Loading." In ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2010. http://dx.doi.org/10.1115/esda2010-24739.
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Honeycomb cellular structures, due to their light weight and high energy absorbing, have been used extensively as energy absorbers or cushions to resist external loads. In this paper, the mean crushing stress and the wavelength of the folding mode, as two important parameters in the study of metal square honeycomb crushing under quasi-static loading have been investigated theoretically and experimentally. Firstly, by considering the true cylindrical curvature effects and the flow stress in the folding mode of the honeycomb material, the Wierzbicki’s model in the study of metal hexagonal honeycomb crushing under quasi-static loading is modified. This modification is performed by rewriting the internal energy terms and the external work in the energy method through the basic element folding by considering the true cylindrical curvature effects and the flow stress of the honeycomb material. Comparison of the results obtained by this modified model and Wierzbicki’s model with the experimental data shows better prediction by the model presented in this paper. Subsequently, this modified model has been extended to the study of metal square honeycombs crushing under quasi-static loading and the mean crushing stress and the wavelength of the folding mode of these structures have been predicted. This analytical model predicts the mean crushing stress of the metal square honeycomb as a function of both the geometrical parameters and its material, while the predicted wavelength of the folding mode is just a function of the geometrical parameters. Finally, the experimental tests have been performed to verify the preciseness of this theoretical model.
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Jia, Xinlong, Nan Gui, Xingtuan Yang, Jiyuan Tu, and Shengyao Jiang. "Experimental and Numerical Study of the Movement Mechanism and Characteristics of the Quasi-Static Pebble Flow." In 2013 21st International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icone21-15371.
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Quasi-static pebble flow, or so-called the very slow pebble flow, in a pebble bed reactor, with evident randomicity and dispersibility, is extremely complex. Improving the knowledge of the movement mechanism of quasi-static pebble flow can be beneficial to the safety of the pebble bed reactor. This study utilizes a phenomenological method and a discrete element method to investigate the interface features of two regions composed of differently colored pebbles. A pseudo-two dimensional experimental setup is established to facilitate the observation of movement of pebble. Then, the DEM simulation is carried out to analyze the further details of particle movement mechanism. To some extent, the two methods are closely related and mutually confirmed. In this study, some special phenomena are observed, such as the non-uniformity, mixing zone, stagnant zones, the propagation of voids, slow flow zone, etc. Moreover, some basic issues on the movement mechanism and characteristics of quasi-static pebble flow are discussed, e.g. the interpretation of force analysis inside the pebble packing, propagation and distribution of voids, formation of equilibrium arches, the effects of stagnant zone on the flow field, and so on. These characteristics of the quasi-static pebble flow are very different from the continuous flow, and the understanding of these characteristics is very helpful for the design and analysis of pebble bed reactors.
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Liu, Yujia, Sifan Peng, Nan Gui, Xingtuan Yang, Jiyuan Tu, and Shengyao Jiang. "Experimental Study on Gravity Driven Discharging of Quasi-Two-Dimensional Pebble Bed Based on Mathematical Morphology." In 2020 International Conference on Nuclear Engineering collocated with the ASME 2020 Power Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/icone2020-16367.
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Abstract The pebbles flow is a fundamental issue for both academic investigation and engineering application in reactor core design and safety analysis. In general, experimental methods including spiral X-ray tomography and refractive index matched scanning technique (RIMS) are applied to obtain the identification of particles’ positions within a three-dimensional pebble bed. However, none of the above methods can perform global bed particles’ position identification in a dynamically discharging pebble bed, and the corresponding experimental equipment is difficult to access due to the complication and high expense. In this research, the experimental study is conducted to observe the gravity driven discharging process in the quasi two-dimensional silos by making use of the high-speed camera and the uniform backlight. A mathematical morphology-based method is applied to the pre-processing of the captured results. After being increased the gray value gradient by the threshold segmentation, the edges of the particles are identified and smoothed by the Sobel algorithm and the morphological opening operation. The particle centroid coordinates are identified according to the Hough circle transformation of the edges. For the whole pebble bed, the self-programmed process has a particle recognition accuracy of more than 99% and a particle centroid position deviation of less than 3%, which can accurately obtain the physical positions of all particles in the entire dynamically discharge process. By analyzing the position evolution of individual particles in consecutive images, velocity field and motion events of particles are observed. The discharging profiles of 5 conditions with different exit are analyzed in this experiment. The results make a contribution to improving the understanding of the mechanism of pebbles flow in nuclear engineering.
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Sawadogo, Teguewinde, and Njuki Mureithi. "A Method for Extracting the Time Delay From the Unsteady and Quasi-Steady Fluidelastic Forces in Two-Phase Flow." In ASME 2013 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/pvp2013-97437.
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The time delay is a key parameter for modeling fluidelastic instability, especially the damping controlled mechanism. It can be determined experimentally by measuring directly the time lag between the tube motion and the induced fluid forces. The fluid forces may be obtained by integrating the pressure field around the moving tube. However, this method faces certain difficulties in two-phase flow since the high turbulence and the non-uniformity of the flow may increase the randomness of the measured force. To overcome this difficulty, an innovative method for extracting the time delay inherent to the quasi-steady model for fluidelastic instability is proposed in this study. Firstly, experimental measurements of unsteady and quasi-static fluid forces (in the lift direction) acting on a tube subject to two-phase flow were conducted. The unsteady fluid forces were measured by exciting the tube using a linear motor. These forces were measured for a wide range of void fraction, flow velocities and excitation frequencies. The experimental results showed that the unsteady fluid forces could be represented as single valued function of the reduced velocity (flow velocity reduced by the excitation frequency and the tube diameter). The time delay was determined by equating the unsteady fluid forces with the quasi-static forces. The results given by this innovative method of measuring the time delay in two-phase flow were consistent with theoretical expectations. The time delay could be expressed as a linear function of the convection time and the time delay parameter was determined for void fractions ranging from 60% to 90%. Fluidelastic instability calculations were also performed using the quasi-steady model with the newly measured time delay parameter. Previously conducted stability tests provided the experimental data necessary to validate the theoretical results of the quasi-steady model. The validity of the quasi-steady model for two-phase flow was confirmed by the good agreement between its results and the experimental data. The newly measured time delay parameter has improved significantly the theoretical results, especially for high void fractions (90%). However, the model could not be verified for void fractions lower or equal to 50% due to the limitation of the current experimental setup. Further studies are consequently required to clarify this point. Nevertheless, this model can be used to simulate the flow induced vibrations in steam generators’ tube bundles as their most critical parts operate at high void fractions (≥ 60%).
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Poursadegh, Farzad, Ali Hajilouy-Benisi, and Mahdi Nili-Ahmadabadi. "A Novel Quasi-3D Design Method for Centrifugal Compressor Impeller on the Blade-to-Blade Plane." In ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/gt2011-45451.
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In this research, a novel quasi-3D design method is developed for the centrifugal compressor impeller on the blade-to-blade plane. In this method, an iterative inverse design method called Ball-Spine Algorithm (BSA) is incorporated into the quasi-3D analysis code solving the Euler equations on the blade-to-blade and meridional planes at each shape modification step. In design procedure, the difference between the target and current pressure distribution along the suction or pressure sides of the impeller causes the blade-to-blade profile to be changed and the target pressure distribution to be satisfied. In order to validate the quasi-3D analysis code, the centrifugal compressor of a gas turbine is investigated numerically using a full 3D Navier-Stokes analysis code. The meridional and blade-to-blade planes pressure distributions obtained from quasi-3D and 3D analysis codes are compared showing good agreement between them. Furthermore, the pressure ratio and efficiency of the centrifugal compressor is obtained by some experiments in which the flow parameters at the compressor inlet and outlet are measured. Comparison of 3D analysis results with the experimental results shows good agreements. Finally, the current pressure distribution along the pressure side at 50% span is smoothed and considered as the target pressure distribution. The quasi-3D design procedure converges to a new profile after 400 modification steps. The designed impeller is numerically analyzed showing the flow pattern of the impeller is improved and the total to static efficiency of impeller increases by 0.64 percent and the total pressure ratio increased by 3.38 percent.
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Fox, D. M., and J. S. Lee. "Application of an Arbitrary Lagrangian Eulerian Method to Describe High Velocity Gas-Particle Flow Behavior." In ASME-JSME-KSME 2011 Joint Fluids Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajk2011-03075.
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Novel computational and small-scale experimental investigations were performed in order to better understand the high velocity flow behavior of gas-particle mixtures. The motion of solid objects impacted by the flow of the mixtures was measured by use of high-speed digital video photography. Computations were performed by use of an arbitrary Lagrangian Eulerian (ALE) treatment in a nonlinear finite element code. Constitutive models for description of the solid component of the gas-particle blend were developed based on quasi-statically determined test results. It was observed that there was very close agreement between experimental and computational results and that it was possible to accurately predict the high velocity flow behavior of the gas-particle mixture using quasi-statically determined constitutive models.
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Arghir, Mihai, and Jean Frene. "A Quasi 2D Method for the Rotordynamic Analysis of Centered Labyrinth Liquid Seals." In ASME 1998 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/98-gt-005.
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The work presents a method for analyzing the dynamic regime of labyrinth liquid seals. By using the traditional simplifying assumptions for the centered seal (sinusoidal, harmonically varying, first order dynamic perturbation), the approach can be addressed as “quasi” 2D. A numerical coordinate transformation capable to treat displacement perturbations is introduced. The first order mathematical model is then deduced following the same steps as in a previously published work (Arghir et Frêne, 1997b). From this standpoint, the present method can be regarded as an extension of the above mentioned approach which was able to deal only with stator-grooved seals. The method is validated by comparisons with Nordmann and Dietzen’s (1988) theoretical results for a seal with grooves on both stator and rotor and with the experimental results of Staubli’s (1993) test case concerning a general seal.
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Wolff, James M., and Sanford Fleeter. "Nonlinear Separated Inviscid–Viscous Analysis of Oscillating Cascade Aerodynamics Using an Inverse Integral Method." In ASME 1997 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/97-gt-085.
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A mathematical model is developed to analyze the unsteady flow through an harmonically oscillating cascade of airfoils, including separated flow. The model incorporates an inverse integral boundary layer solution with the time–marching Euler analysis NPHASE. An embedded composite grid formulation is incorporated, specifically a deforming C–grid embedded in a Cartesian H–grid, thereby simplifying grid generation. To reduce computational requirements, Fourier series unsteady periodic boundary conditions are implemented. The integral turbulent boundary layer model is closed with steady correlations adopted in a quasi–steady manner. To couple the inviscid and viscous solutions, the viscous effect is modeled in the unsteady Euler solution in a quasi–steady manner by a transpiration boundary condition. An isolated airfoil is used to compare the steady interaction model with experimental data. Then a flat plate cascade is used to verify the unsteady flow solver with linear theory predictions. An experimental unsteady aerodynamics data set of a loaded cascade with separated meanflow executing torsional oscillations compared favorably with the analysis. The code is then utilized to study the effect of flow separation on the unsteady aerodynamics.
Reports on the topic "Quasi-experimental method"
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Deschenes, Olivier, and Kyle Meng. Quasi-Experimental Methods in Environmental Economics: Opportunities and Challenges. Cambridge, MA: National Bureau of Economic Research, August 2018. http://dx.doi.org/10.3386/w24903.
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Zanoni, Wladimir, and Ailin He. Citizenship and the Economic Assimilation of Canadian Immigrants. Inter-American Development Bank, March 2021. http://dx.doi.org/10.18235/0003117.
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In this paper, we examine whether acquiring citizenship improves the economic assimilation of Canadian migrants. We took advantage of a natural experiment made possible through changes in the Canadian Citizenship Act of 2014, which extended the physical presence requirement for citizenship from three to four years. Using quasi-experimental methods, we found that delaying citizenship eligibility by one year adversely affected Canadian residents' wages. Access to better jobs explains a citizenship premium of 11 percent in higher wages among naturalized migrants. Our estimates are robust to model specifications, differing sampling windows to form the treatment and comparison groups, and whether the estimator is a non-parametric rather than a parametric one. We discuss how our findings are relevant to the optimal design of naturalization policies regarding efficiency and equity.
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Wiecha, Jean L., and Mary K. Muth. Agreements Between Public Health Organizations and Food and Beverage Companies: Approaches to Improving Evaluation. RTI Press, January 2021. http://dx.doi.org/10.3768/rtipress.2021.op.0067.2101.
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Efforts in the United States and abroad to address the chronic disease epidemic have led to the emergence of voluntary industry agreements as a substitute for regulatory approaches to improve the healthfulness of foods and beverages. Because of the lack of access to data and limited budgets, evaluations of these agreements have often been limited to process evaluation with less focus on outcomes and impact. Increasing scientific scope and rigor in evaluating voluntary food and beverage industry agreements would improve potential public health benefits and understanding of the effects of these agreements. We describe how evaluators can provide formative, process, and outcome assessment and discuss challenges and opportunities for impact assessment. We explain how logic models, industry profiles, quasi-experimental designs, mixed-methods approaches, and third-party data can improve the effectiveness of agreement design and evaluation. These methods could result in more comprehensive and rigorous evaluation of voluntary industry agreements, thus providing data to bolster the public health impacts of future agreements. However, improved access to data and larger evaluation budgets will be needed to support improvements in evaluation.