Syfte: Studiens syfte var att undersöka samband mellan hur universitetsstudenter skattar sin fysiska aktivitetsnivå och hur de registrerar aktivitetsnivå med hjälp av dagbok samt att se om de kom upp i ACSM (American College of Sport Medicine) och WHO´s (World Health Organisation) rekommendationer. Metod: Studien hade en icke experimentell, deskriptiv och korrelerande design där 26 försökspersoner, två män och 24 kvinnor, rekryterades via anslag. De fick först svara på en enkät och därefter registrera sin aktivitet via en 7-dagars aktivitetsdagbok. Resultat: Studenterna ansåg inte att de hade en stillasittande livsstil och alla deltagare utom en ansåg sig komma upp till ACSM´s rekommendationer av fysisk aktivitet 30 minuter per dag av måttlig intensitet alla dagar i veckan. Trettiofem procent kom inte upp i WHO´s rekommendationer och av dessa överskattade 67% sin fysiska aktivitetsnivå. Sextiofem procent kom inte upp i ACSM´s rekommendationer och av dessa överskattade 94% sin aktivitetsnivå. Konklusion: Studenterna hade en låg fysisk aktivitetsnivå utifrån ACSM´s rekommendationer och majoriteten av de som inte levde upp till WHO och ACSM rekommendationer överskattade sin fysiska aktivitetsnivå. Det krävs dock mer omfattande studier för att dra några generella slutsatser då denna studie hade en skev könsfördelning och ett lågt antal deltagare. Keywords: Self-estimation, Perception, Activity diary, Physical Activity level, Overestimation. / Objectives: The main objective was to compare self-estimated physical activity level with the registration of physical activity level among college students. A secondary objective was to investigate if the subjects reached the level of physical activity recommended by American College of Sport Medicine (ACSM) and World Health Organisation (WHO). Method: A non-experimental, descriptive and correlated design. 26 subjects, 2 men and 24 women, were included. A questionnaire was used to investigate their perceived level of physical activity and a 7-day activity diary was used for the registration of activity level. Results: The students did not perceive to have a sedentary lifestyle and all subjects except one believed they reached the level recommended by ACSM. Thirty-five percent did not reach the recommendations of WHO and 67% of these overestimated their physical activity level. Sixty-five percent did not reach ACSM´s recommendations and 94% of these overestimated their physical activity level. Conclusion: The students had a low physical activity compared to the recommendations of ACSM and subjects who did not reach WHO and ACSM´s recommendations overestimated their physical activity level.  Due to the small number and adverse gender in the subjects, numerous studies need to be done in order to complete any further conclusions.

No description available.

Free analyte is measured to be able to understand the pharmacological effects of a drug in the body, the binding to its ligand, and the effective drug level among other things. Thereby, it is important with correct measurements of free analyte, although it is not that easy to achieve since overestimations can occur. In this project, several immunoassays were developed for the bioanalytical methods Gyrolab and ELISA to measure free analyte, where the biotherapeutics Avastin® and Lucentis®, and the ligand VEGF were used as analytes. One difference between the methods is the short contact time of just a few seconds for Gyrolab compared to the sample incubation time of a couple of hours for ELISA. One difference between the antibodies is that Lucentis is an affinity-matured Fab region, and therefore, has a stronger affinity to VEGF compared to Avastin. When free Avastin was measured, the difference was significant, with ELISA estimating higher concentrations compared to Gyrolab. However, this was not the case for all assays. In some cases, this was probably due to differences between the methods that could not be seen. Otherwise, the results with no difference between the methods, when measuring free analyte with Lucentis as the drug, were expected due to the stronger affinity and longer halftime of dissociation. However, the difference with the longer sample incubation time for ELISA compared to the short contact time for Gyrolab seems to influence the measurement of free analyte, depending on the affinity of the components being measured.

Wind farms are costly projects and prior to the construction, comprehensive wind resource assessment processes are carried out in order to predict the future energy yield with a reliable accuracy. These estimations are made to constitute a basis for the financial assessment of the project. However, predicting the future always accommodates some uncertainties and sometimes these assessments might overestimate the production. Many different factors might account for a discrepancy between the pre-construction wind resource assessment and the operational production data. This thesis investigates an underperforming wind farm in order to ascertain the reasons of a discrepancy case. To investigate the case, the relevant data and information along with the actual production data of three years are shared with the author. Prior to the construction, a wind resource assessment was carried out by an independent wind consultancy company and the work overestimated the annual energy production (AEP) by 19.1% based on the average production value of available three years. An extensive literature review is performed to identify the possible contributing causes of the discrepancy. The data provided is investigated and a new wind resource assessment is carried out. The underestimation of the wind farm losses are studied extensively as a potential reason of the underperformance. For the AEP estimations, WAsP in WindPro interface and WindSim are employed. The use of WindSim led to about 2-2.5% less AEP estimations compared to the results of WAsP. In order to evaluate the influence of long term correlations on the AEP estimations, the climatology datasets are created using the two different reanalysis datasets (MERRA and CFSR-E) as long term references. WindSim results based on the climatology data obtained using the MERRA and CFSR-E datasets as long term references overestimated the results by 10.9% and 8.2% respectively.

The amount of information in the world has grown exponentially in the last generation. Students often believe that growing up as digital natives means they have advanced information literacy skills. However, school librarians are not seeing evidence of this in their schools. The purpose of this study was to determine if secondary students overestimate their information literacy (IL) abilities, if relationships exist between IL self-efficacy and performance, and if grade level or self-efficacy level changes those relationships. To accomplish this, data were collected from two middle schools and three high schools from a total of 397 students in grades 6, 9, and 12. Students completed the Information Literacy Self-efficacy Scale (ILSES) and the Tool for Real-time Assessment of Information Literacy Skills (TRAILS) to measure their IL self-efficacy and performance. The data were examined as a whole, by grade level, by self-efficacy level, and by a breakdown of combined self-efficacy level and grade level. Analyses involved t-tests, bivariate correlations, and hierarchical linear regression. Results showed that all groups overestimated their IL abilities and that the overestimation increased as self-efficacy level increased. In addition, correlations provided evidence of a relationship between IL self-efficacy and performance for each grade level and for each self-efficacy level. Another finding was that in all grade levels, higher self-efficacy equated to higher performance, however, for a large percent of students, high self-efficacy equated with lower scores. Grade level did have an effect on the relationship between IL self-efficacy and performance. This effect showed statistical and practical significance when grade level was used as a covariate but only practical significance when used as a moderating variable. Overall, ninth graders showed a dip in performance when compared to sixth and twelfth grades.

No description available.

Cette thèse contribue à la littérature économique sur les compétences non cognitives essentielles pour la réussite de la vie, particulièrement pour la réussite scolaire. Elle comprend quatre essais basés sur des approches économiques comportementales et expérimentales, avec deux objectifs principaux. Le premier objectif est d’étudier deux compétences non cognitives, à savoir la confiance en soi et la créativité. Notre but est alors de comprendre les déterminants de la confiance en soi et l’impact de la créativité sur les résultats économiques. Le deuxième objectif est d’étudier comment le système scolaire influence les décisions éducatives, les résultats scolaires et la mobilité intergénérationnelle, secteurs où les compétences non cognitives peuvent jouer un rôle important, en particulier via leurs effets sur la confiance en soi et la motivation. Nous observons un impact important des capacités non cognitives sur le comportement et sur les résultats économiques, notamment en ce qui concerne les décisions éducatives. Tout nous montre à penser que fondamentalement les écoles s’inquiètent du développement de ces capacités non cognitives - et non pas seulement des capacités cognitives. Aider les élèves à avoir de meilleures estimations de leur confiance en soi, favoriser le développement du potentiel créatif, stimuler la motivation et l’effort devraient alors faire partie de l’éducation que les élèves reçoivent dans les écoles ; promouvant alors de meilleures décisions, de meilleurs résultats et une société plus équitable. / This thesis contributes to the growing economic literature on noncognitive skills that are critical for life success, specially for academic success. It comprises four essays based on behavioral and experimental economics approaches, with two main objectives. The first objective is to study two noncognitive skills, namely self-confidence and creativity. We aim at understanding the determinants of self-confidence, and the impact of creative potential on economic outcomes. The second objective is to study how school systems impact educational decisions, educational outcomes and intergenerational mobility, where noncognitive skills may play an important role, specially self-confidence and motivation. We observe an important impact of the noncognitive abilities on behavior and economic results, especially for the educational achievements. Taken all our evidences together, it seems fundamental that schools worry about the development of these noncognitive abilities - and not only of the cognitive abilities. Helping students to have better estimates of self-confidence, favoring the development of creative potential, and stimulating motivation and effort should be part of the education that pupils receive in schools ; promoting then better decisions, better outcomes and a more equitable society.

Les données d’enquêtes jouent un rôle primordial dans la production scientifique en sciences sociales. Cependant, la présence de biais dans les données au moment de la collecte, y compris les erreurs de réponse et de non-réponse, pourrait affecter la fiabilité des résultats obtenus. Bien que le problème des erreurs de réponse et de non-réponse soit largement discuté, la littérature existante s’intéresse peu aux mécanismes par lesquels ces erreurs influencent les mesures estimées. Par conséquent, l’objectif principal de cette thèse est d’apporter une contribution méthodologique à la compréhension des estimations d’enquêtes en présence de données erronées et manquantes, en déterminant leur part explicative dans les modèles estimés. À l’aide de deux mesures répétées de l’âge de la première consommation de substances psychoactives recueillies par l’ELNEJ (1994-2009) auprès de jeunes Canadiens à l’âge de 12-13 ans, puis à l’âge de 14-15 ans, cette thèse par articles visait à étudier : (1) les types d’incohérences ou de biais imputés dans la deuxième mesure comparativement à la première (mesure de référence) et ainsi déduire les caractéristiques des répondants dont les déclarations sont incohérentes (Article 1); (2) l’impact de ces biais dans la détermination des prédicteurs de la consommation précoce, c’est-à-dire à l’âge de 13 ans ou moins (Article 2); et (3) leur impact sur la prédiction de la consommation à l’âge de 16-17 ans en fonction de l’âge d’initiation (Article 3). L’impact du biais est déterminé en corrigeant (1) le biais de sélection dû à la censure des répondants ayant des déclarations incohérentes de l’échantillon de l’étude, lorsque l’âge de l’initiation est la variable dépendante dans le modèle estimé (Article 2) ou (2) le biais d’endogénéité dû à la présence de valeurs erronées et manquantes dans l’âge d’initiation, lorsque l’âge d’initiation est une variable explicative dans le modèle estimé (Article 3). Le premier article révèle qu’au deuxième passage de l’enquête, les jeunes de 14-15 ans ne fournissent pas nécessairement des âges d’initiation cohérents avec ceux fournis lorsqu’ils avaient 12-13 ans. La proportion d’incohérence enregistrée n’est pas négligeable; elle est de 43 % pour l’alcool, 33 % pour le tabac et 32 % pour la drogue. Ces jeunes sont susceptibles de déclarer des âges d’initiation plus tardifs ou d’omettre l’expérimentation antérieure (biais télescopique vers l’avant: BTA), des âges d’initiation plus hâtifs (biais télescopique vers l’arrière: BTR), et peuvent également ne pas déclarer leur initiation à au moins un des deux cycles d’enquête (Biais non-déclaré : BND). Les résultats de la régression multinomiale montrent que le risque de détecter ces biais n’est pas le fruit du hasard; il varie en fonction des caractéristiques socio-démographiques et personnelles des répondants, notamment le genre, la structure de la famille et la région de résidence. En raison du biais dans la deuxième déclaration de l'âge d'initiation, le deuxième article démontre que l'identification des groupes à risque de consommation précoce est affectée par le potentiel de biais au sein de ces groupes. En utilisant l'approche de Heckman, il a été conclu que les âges d'initiation déclarés plus hâtifs (plus tardifs) génèrent une surestimation (sous-estimation) des risques de consommation précoce (à 13 ans et moins) dans les groupes les plus susceptibles de fournir des âges biaisés vers l'arrière BTR (biaisés vers l'avant BTA). Cependant, ces risques sont sous-estimés dans les groupes qui n’ont pas déclaré leur âge d’initiation lors du premier passage de l’enquête (BND). Ceci indique que pour ces groupes, l’âge d’initiation qui n’a pas été déclaré lors du premier passage est probablement un âge précoce (autour de 12-13 ans). Le troisième article conclut que les biais attribués à l'âge de l'initiation affectent l’estimation de la relation entre l’âge d’initiation et la fréquence de consommation à l'âge de 16-17 ans. Le fait que cette relation soit surestimée ou sous-estimée dépend spécifiquement du type de biais et de sa corrélation avec la consommation ultérieure. Enfin, cette thèse tente de fournir des preuves empiriques mettant en évidence le biais de réponse et de non-réponse comme une source d'information supplémentaire qui caractérise l'échantillon de l'étude et qui sa propre part explicative dans les modèles estimés. La validité des données d'enquête est donc d'une grande utilité pour la validité des résultats des études. / Survey data play an essential role in scientific production in the social sciences. However, the presence of bias in the data at the time of collection, including response and non-response errors, could affect the reliability of the results obtained. Although the problem of response and nonresponse errors is widely discussed, little attention has been paid in the existing literature to the mechanisms by which these errors influence the estimated measures. Therefore, the main objective of this thesis is to make a methodological contribution to the understanding of survey estimates in the presence of erroneous and missing data, by determining their explanatory part in the estimated models. Using two repeated measures of age at first substance use collected by the NLSCY (1994-2009) from Canadian youth, when they were 12-13 years old and again at 14-15 years old, this article-based dissertation aimed to investigate: (1) the types of inconsistencies or biases imputed in the second measure relative to the first (baseline) measure and thus infer the characteristics of respondents whose reports are inconsistent (Paper 1); (2) the impact of these biases in determining predictors of early use, i.e., at age 13 and younger (Paper 2); and (3) their impact on predicting use at age 16-17 as a function of age of initiation (Paper 3). The impact of bias is determined by correcting for (1) selection bias due to censoring of respondents with inconsistent reports from the sample, when age of initiation is the dependent variable in the estimated model (Paper 2) and (2) endogeneity bias due to the presence of erroneous and missing values in age of initiation, when age of initiation has an explanatory variable in the estimated model (Paper 3). The first article reveals that at the second survey round, 14–15 years old do not necessarily provide ages of initiation consistent with those provided when they were 12-13 years old. The proportion of inconsistency recorded is not negligible; it is 43% for alcohol, 33% for tobacco, and 32% for drugs. These youth are likely to report later ages of initiation or omit previous experimentation (telescopic forward bias: BTA), earlier ages of initiation (telescopic backward bias: BTR) and may also fail to report initiation on at least one of the two survey rounds (unreported bias: BND). Multinomial regression results show that the risk of detecting these biases is not random; it varies with respondents' socio-demographic and personal characteristics, including gender, family structure, and region of residence. Because of the bias in the second report on age of initiation, the second article demonstrates that the identification of groups at risk for early use is affected by the potential for bias within these groups. Using Heckman's approach, it was concluded that earlier (later) reported initiation ages generate an overestimation (underestimation) of the risks of early use (at age 13 and younger) in the groups most likely to provide backward-biased (forward-biased) ages. However, this risk is underestimated in groups that did not report their age of initiation at the first survey round (BND). This indicates that for these groups, the age of initiation that was not reported in the first round is likely to be an early age (around 12-13 years). The third paper concludes that biases attributed to age of initiation affect the estimate of the relationship between age of initiation and frequency of use at age 16-17. Whether this relationship is overestimated or underestimated depends specifically on the type of bias and its correlation with later use. Finally, this thesis attempts to provide empirical evidence highlighting response and nonresponse bias as an additional source of information that characterizes the study sample and has its own explanatory part in the estimated models. The validity of survey data is thus of great benefit to the validity of studies results.

Nichtglatte Optimierungsprobleme in reflexiven Banachräumen treten in vielen Anwendungen auf. Häufig wird angenommen, dass alle vorkommenden Nichtdifferenzierbarkeiten durch Lipschitz-stetige Operatoren wie abs, min und max gegeben sind. Bei solchen Problemen kann es sich zum Beispiel um optimale Steuerungsprobleme mit möglicherweise nicht glatten Zielfunktionen handeln, welche durch partielle Differentialgleichungen (PDG) eingeschränkt sind, die ebenfalls nicht glatte Terme enthalten können. Eine effiziente und robuste Lösung erfordert eine Kombination numerischer Simulationen und spezifischer Optimierungsalgorithmen. Lokal Lipschitz-stetige, nichtglatte Nemytzkii-Operatoren, welche direkt in der Problemformulierung auftreten, spielen eine wesentliche Rolle in der Untersuchung der zugrundeliegenden Optimierungsprobleme. In dieser Dissertation werden zwei spezifische Methoden und Algorithmen zur Lösung solcher nichtglatter Optimierungsprobleme in reflexiven Banachräumen vorgestellt und diskutiert. Als erste Lösungsmethode wird in dieser Dissertation die Minimierung von nichtglatten Operatoren in reflexiven Banachräumen mittels sukzessiver quadratischer Überschätzung vorgestellt, SALMIN. Ein neuartiger Optimierungsansatz für Optimierungsprobleme mit nichtglatten elliptischen PDG-Beschränkungen, welcher auf expliziter Strukturausnutzung beruht, stellt die zweite Lösungsmethode dar, SCALi. Das zentrale Merkmal dieser Methoden ist ein geeigneter Umgang mit Nichtglattheiten. Besonderes Augenmerk liegt dabei auf der zugrundeliegenden nichtglatten Struktur des Problems und der effektiven Ausnutzung dieser, um das Optimierungsproblem auf angemessene und effiziente Weise zu lösen. / Non-smooth optimization problems in reflexive Banach spaces arise in many applications. Frequently, all non-differentiabilities involved are assumed to be given by Lipschitz-continuous operators such as abs, min and max. For example, such problems can refer to optimal control problems with possibly non-smooth objective functionals constrained by partial differential equations (PDEs) which can also include non-smooth terms. Their efficient as well as robust solution requires numerical simulations combined with specific optimization algorithms. Locally Lipschitz-continuous non-smooth non-linearities described by appropriate Nemytzkii operators which arise directly in the problem formulation play an essential role in the study of the underlying optimization problems. In this dissertation, two specific solution methods and algorithms to solve such non-smooth optimization problems in reflexive Banach spaces are proposed and discussed. The minimization of non-smooth operators in reflexive Banach spaces by means of successive quadratic overestimation is presented as the first solution method, SALMIN. A novel structure exploiting optimization approach for optimization problems with non-smooth elliptic PDE constraints constitutes the second solution method, SCALi. The central feature of these methods is the appropriate handling of non-differentiabilities. Special focus lies on the underlying structure of the problem stemming from the non-smoothness and how it can be effectively exploited to solve the optimization problem in an appropriate and efficient way.

In dieser Arbeit wird ein Algorithmus zur Lösung von endlichdimensionalen Optimierungsproblemen mit stückweise linearer Zielfunktion und stückweise linearen Nebenbedingungen vorgestellt. Dabei wird angenommen, dass die Funktionen in der sogenannten Abs-Linear Form, einer Matrix-Vektor-Darstellung, vorliegen. Mit Hilfe dieser Form lässt sich der Urbildraum in Polyeder zerlegen, so dass die Nichtglattheiten der stückweise linearen Funktionen mit den Kanten der Polyeder zusammenfallen können. Für die Klasse der abs-linearen Funktionen werden sowohl für den unbeschränkten als auch für den beschränkten Fall notwendige und hinreichende Optimalitätsbedingungen bewiesen, die in polynomialer Zeit verifiziert werden können. Für unbeschränkte stückweise lineare Optimierungsprobleme haben Andrea Walther und Andreas Griewank bereits 2019 mit der Active Signature Method (ASM) einen Lösungsalgorithmus vorgestellt. Aufbauend auf dieser Methode und in Kombination mit der Idee der aktiven Mengen Strategie zur Behandlung von Ungleichungsnebenbedingungen entsteht ein neuer Algorithmus mit dem Namen Constrained Active Signature Method (CASM) für beschränkte Probleme. Beide Algorithmen nutzen die stückweise lineare Struktur der Funktionen explizit aus, indem sie die Abs-Linear Form verwenden. Teil der Analyse der Algorithmen ist der Nachweis der endlichen Konvergenz zu lokalen Minima der jeweiligen Probleme sowie die Betrachtung effizienter Berechnung von Lösungen der in jeder Iteration der Algorithmen auftretenden Sattelpunktsysteme. Die numerische Performanz von CASM wird anhand verschiedener Beispiele demonstriert. Dazu gehören akademische Probleme, einschließlich bi-level und lineare Komplementaritätsprobleme, sowie Anwendungsprobleme aus der Gasnetzwerkoptimierung und dem Einzelhandel. / This thesis presents an algorithm for solving finite-dimensional optimization problems with a piecewise linear objective function and piecewise linear constraints. For this purpose, it is assumed that the functions are in the so-called Abs-Linear Form, a matrix-vector representation. Using this form, the domain space can be decomposed into polyhedra, so that the nonsmoothness of the piecewise linear functions can coincide with the edges of the polyhedra. For the class of abs-linear functions, necessary and sufficient optimality conditions that can be verified in polynomial time are given for both the unconstrained and the constrained case. For unconstrained piecewise linear optimization problems, Andrea Walther and Andreas Griewank already presented a solution algorithm called the Active Signature Method (ASM) in 2019. Building on this method and combining it with the idea of the Active Set Method to handle inequality constraints, a new algorithm called the Constrained Active Signature Method (CASM) for constrained problems emerges. Both algorithms explicitly exploit the piecewise linear structure of the functions by using the Abs-Linear Form. Part of the analysis of the algorithms is to show finite convergence to local minima of the respective problems as well as an efficient solution of the saddle point systems occurring in each iteration of the algorithms. The numerical performance of CASM is illustrated by several examples. The test problems cover academic problems, including bi-level and linear complementarity problems, as well as application problems from gas network optimization and inventory problems.