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Empirical essays on job search behavior, active labor market policies, and propensity score balancing methodsSchmidl, Ricarda January 2014 (has links)
In Chapter 1 of the dissertation, the role of social networks is analyzed as an important determinant in the search behavior of the unemployed. Based on the hypothesis that the unemployed generate information on vacancies through their social network, search theory predicts that individuals with large social networks should experience an increased productivity of informal search, and reduce their search in formal channels. Due to the higher productivity of search, unemployed with a larger network are also expected to have a higher reservation wage than unemployed with a small network. The model-theoretic predictions are tested and confirmed empirically. It is found that the search behavior of unemployed is significantly affected by the presence of social contacts, with larger networks implying a stronger substitution away from formal search channels towards informal channels. The substitution is particularly pronounced for passive formal search methods, i.e., search methods that generate rather non-specific types of job offer information at low relative cost. We also find small but significant positive effects of an increase of the network size on the reservation wage. These results have important implications on the analysis of the job search monitoring or counseling measures that are usually targeted at formal search only.
Chapter 2 of the dissertation addresses the labor market effects of vacancy information during the early stages of unemployment. The outcomes considered are the speed of exit from unemployment, the effects on the quality of employment and the short-and medium-term effects on active labor market program (ALMP) participation. It is found that vacancy information significantly increases the speed of entry into employment; at the same time the probability to participate in ALMP is significantly reduced. Whereas the long-term reduction in the ALMP arises in consequence of the earlier exit from unemployment, we also observe a short-run decrease for some labor market groups which suggest that caseworker use high and low intensity activation measures interchangeably which is clearly questionable from an efficiency point of view. For unemployed who find a job through vacancy information we observe a small negative effect on the weekly number of hours worked.
In Chapter 3, the long-term effects of participation in ALMP are assessed for unemployed youth under 25 years of age. Complementary to the analysis in Chapter 2, the effects of participation in time- and cost-intensive measures of active labor market policies are examined. In particular we study the effects of job creation schemes, wage subsidies, short-and long-term training measures and measures to promote the participation in vocational training. The outcome variables of interest are the probability to be in regular employment, and participation in further education during the 60 months following program entry. The analysis shows that all programs, except job creation schemes have positive and long-term effects on the employment probability of youth. In the short-run only short-term training measures generate positive effects, as long-term training programs and wage subsidies exhibit significant locking-in'' effects. Measures to promote vocational training are found to increase the probability of attending education and training significantly, whereas all other programs have either no or a negative effect on training participation. Effect heterogeneity with respect to the pre-treatment level education shows that young people with higher pre-treatment educational levels benefit more from participation most programs. However, for longer-term wage subsidies we also find strong positive effects for young people with low initial education levels. The relative benefit of training measures is higher in West than in East Germany.
In the evaluation studies of Chapters 2 and 3 semi-parametric balancing methods of Propensity Score Matching (PSM) and Inverse Probability Weighting (IPW) are used to eliminate the effects of counfounding factors that influence both the treatment participation as well as the outcome variable of interest, and to establish a causal relation between program participation and outcome differences. While PSM and IPW are intuitive and methodologically attractive as they do not require parametric assumptions, the practical implementation may become quite challenging due to their sensitivity to various data features. Given the importance of these methods in the evaluation literature, and the vast number of recent methodological contributions in this field, Chapter 4 aims to reduce the knowledge gap between the methodological and applied literature by summarizing new findings of the empirical and statistical literature and practical guidelines for future applied research. In contrast to previous publications this study does not only focus on the estimation of causal effects, but stresses that the balancing challenge can and should be discussed independent of question of causal identification of treatment effects on most empirical applications. Following a brief outline of the practical implementation steps required for PSM and IPW, these steps are presented in detail chronologically, outlining practical advice for each step. Subsequently, the topics of effect estimation, inference, sensitivity analysis and the combination with parametric estimation methods are discussed. Finally, new extensions of the methodology and avenues for future research are presented. / In Kapitel 1 der Dissertation wird die Rolle von sozialen Netzwerken als Determinante im Suchverhalten von Arbeitslosen analysiert. Basierend auf der Hypothese, dass Arbeitslose durch ihr soziales Netzwerk Informationen über Stellenangebote generieren, sollten Personen mit großen sozialen Netzwerken eine erhöhte Produktivität ihrer informellen Suche erfahren, und ihre Suche in formellen Kanälen reduzieren. Durch die höhere Produktivität der Suche sollte für diese Personen zudem der Reservationslohn steigen. Die modelltheoretischen Vorhersagen werden empirisch getestet, wobei die Netzwerkinformationen durch die Anzahl guter Freunde, sowie Kontakthäufigkeit zu früheren Kollegen approximiert wird. Die Ergebnisse zeigen, dass das Suchverhalten der Arbeitslosen durch das Vorhandensein sozialer Kontakte signifikant beeinflusst wird. Insbesondere sinkt mit der Netzwerkgröße formelle Arbeitssuche - die Substitution ist besonders ausgeprägt für passive formelle Suchmethoden, d.h. Informationsquellen die eher unspezifische Arten von Jobangeboten bei niedrigen relativen Kosten erzeugen. Im Einklang mit den Vorhersagen des theoretischen Modells finden sich auch deutlich positive Auswirkungen einer Erhöhung der Netzwerkgröße auf den Reservationslohn.
Kapitel 2 befasst sich mit den Arbeitsmarkteffekten von Vermittlungsangeboten (VI) in der frühzeitigen Aktivierungsphase von Arbeitslosen. Die Nutzung von VI könnte dabei eine „doppelte Dividende“ versprechen. Zum einen reduziert die frühe Aktivierung die Dauer der Arbeitslosigkeit, und somit auch die Notwendigkeit späterer Teilnahme in Arbeitsmarktprogrammen (ALMP). Zum anderen ist die Aktivierung durch Information mit geringeren locking-in‘‘ Effekten verbunden als die Teilnahme in ALMP. Ziel der Analyse ist es, die Effekte von frühen VI auf die Eingliederungsgeschwindigkeit, sowie die Teilnahmewahrscheinlichkeit in ALMP zu messen. Zudem werden mögliche Effekte auf die Qualität der Beschäftigung untersucht. Die Ergebnisse zeigen, dass VI die Beschäftigungswahrscheinlichkeit signifikant erhöhen, und dass gleichzeitig die Wahrscheinlichkeit in ALMP teilzunehmen signifikant reduziert wird. Für die meisten betrachteten Subgruppen ergibt sich die langfristige Reduktion der ALMP Teilnahme als Konsequenz der schnelleren Eingliederung. Für einzelne Arbeitsmarktgruppen ergibt sich zudem eine frühe und temporare Reduktion, was darauf hinweist, dass Maßnahmen mit hohen und geringen „locking-in“ Effekten aus Sicht der Sachbearbeiter austauschbar sind, was aus Effizienzgesichtspunkten fragwürdig ist. Es wird ein geringer negativer Effekt auf die wöchentliche Stundenanzahl in der ersten abhängigen Beschäftigung nach Arbeitslosigkeit beobachtet.
In Kapitel 3 werden die Langzeiteffekte von ALMP für arbeitslose Jugendliche unter 25 Jahren ermittelt. Die untersuchten ALMP sind ABM-Maßnahmen, Lohnsubventionen, kurz-und langfristige Maßnahmen der beruflichen Bildung sowie Maßnahmen zur Förderung der Teilnahme an Berufsausbildung. Ab Eintritt in die Maßnahme werden Teilnehmer und Nicht-Teilnehmer für einen Zeitraum von sechs Jahren beobachtet. Als Zielvariable wird die Wahrscheinlichkeit regulärer Beschäftigung, sowie die Teilnahme in Ausbildung untersucht. Die Ergebnisse zeigen, dass alle Programme, bis auf ABM, positive und langfristige Effekte auf die Beschäftigungswahrscheinlichkeit von Jugendlichen haben. Kurzfristig finden wir jedoch nur für kurze Trainingsmaßnahmen positive Effekte, da lange Trainingsmaßnahmen und Lohnzuschüsse mit signifikanten locking-in‘‘ Effekten verbunden sind. Maßnahmen zur Förderung der Berufsausbildung erhöhen die Wahrscheinlichkeit der Teilnahme an einer Ausbildung, während alle anderen Programme keinen oder einen negativen Effekt auf die Ausbildungsteilnahme haben. Jugendliche mit höherem Ausbildungsniveau profitieren stärker von der Programmteilnahme. Jedoch zeigen sich für längerfristige Lohnsubventionen ebenfalls starke positive Effekte für Jugendliche mit geringer Vorbildung. Der relative Nutzen von Trainingsmaßnahmen ist höher in West- als in Ostdeutschland.
In den Evaluationsstudien der Kapitel 2 und 3 werden die semi-parametrischen Gewichtungsverfahren Propensity Score Matching (PSM) und Inverse Probability Weighting (IPW) verwendet, um den Einfluss verzerrender Faktoren, die sowohl die Maßnahmenteilnahme als auch die Zielvariablen beeinflussen zu beseitigen, und kausale Effekte der Programmteilahme zu ermitteln. Während PSM and IPW intuitiv und methodisch sehr attraktiv sind, stellt die Implementierung der Methoden in der Praxis jedoch oft eine große Herausforderung dar. Das Ziel von Kapitel 4 ist es daher, praktische Hinweise zur Implementierung dieser Methoden zu geben. Zu diesem Zweck werden neue Erkenntnisse der empirischen und statistischen Literatur zusammengefasst und praxisbezogene Richtlinien für die angewandte Forschung abgeleitet. Basierend auf einer theoretischen Motivation und einer Skizzierung der praktischen Implementierungsschritte von PSM und IPW werden diese Schritte chronologisch dargestellt, wobei auch auf praxisrelevante Erkenntnisse aus der methodischen Forschung eingegangen wird. Im Anschluss werden die Themen Effektschätzung, Inferenz, Sensitivitätsanalyse und die Kombination von IPW und PSM mit anderen statistischen Methoden diskutiert. Abschließend werden neue Erweiterungen der Methodik aufgeführt.
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Il Ruolo dei Programmi Agro-ambientali: un'analisi attraverso il Propensity Score Matching e la Programmazione Matematica Positiva con il Rischio / THE ROLE OF EU AGRI-ENVIRONMENTAL PROGRAMMES: A FARM LEVEL ANALYSIS BY PROPENSITY SCORE MATCHING AND BY POSITIVE MATHEMATICAL PROGRAMMING INCORPORATING RISKARATA, LINDA 19 February 2014 (has links)
La crescente attenzione riguardo l’interconnessione tra agricoltura e aspetti ambientali così come la crescita di volatilità dei prezzi dei prodotti agricoli ha posto una nuova enfasi sull’introduzione di misure ambientali nella politiche agricole e sulla ricerca di nuovi strumenti di stabilizzazione del reddito degli agricoltori. La ricerca di questa tesi di dottorato si inserisce in questo contesto e analizza i contratti agro-ambientali, misure della Politica Agricola Comunitaria (PAC) in Unione Europea (UE), sotto una duplice prospettiva. Il primo lavoro di ricerca consiste in un’analisi degli effetti dell’adesione a tali contratti sulle scelte produttive e sulle perfomance economiche degli agricoltori in cinque Paesi dell’UE. I risultati indicano un’eterogeneità di questi effetti: in alcuni Paesi i contratti agro-ambientali sembrano essere più efficaci nel promuovere pratiche agricole sostenibili, così come in alcuni Paesi il pagamento compensativo agro-ambientale sembra non essere sufficiente a compensare la perdita di reddito dei partecipanti. Questo studio è stato condotto combinando il Propensity Score Matching con lo stimatore Difference-in-Differences. Il secondo lavoro di ricerca sviluppa una nuova proposta metodologica che incorpora il rischio in un framework di Programmazione Matematica Positiva (PMP). Il modello elaborato presenta caratteri innovativi rispetto alla letteratura sull’argomento e permette di stimare simultaneamente i prezzi ombra delle risorse, la funzione di costo non lineare dell’azienda agricola e un coefficiente di avversione al rischio specifico per ciascuna azienda. Il modello è stato applicato a tre campioni di aziende e i risultati delle stime testano la calibrazione del modello e indicano valori del coefficiente di avversione al rischio coerenti con la letteratura. Infine il modello è stato impiegato nella simulazione di diversi scenari al fine di verificare il ruolo potenziale di un contratto agro-ambientale come strumento di gestione del rischio a diversi livelli di volatilità dei prezzi agricoli. / The increasing attention to the relationship between agriculture and the environment and the rise in price volatility on agricultural markets has led to a new emphasis on agri-environmental policies as well as to a search for new risk management strategies for the farmer. The research objective of this PhD thesis is in line with this challenging context, since it provides an analysis of the EU agri-environmental schemes (AESs) from two viewpoints. First, an ex-post analysis aims at investigating the AESs for their traditional role as measures which encourage sustainable farming while compensating the farmer for the income foregone in five EU Member States. The effects of AESs participation on farmer’s production plans and economic performances differs widely across Member States and in some of them the environmental payment is not enough to compensate the income foregone of participants. This study has been performed by applying a semi-parametric technique which combines a Difference-in-Differences estimator with a Propensity Score Matching estimator. The second piece of research develops a new methodological proposal to incorporate risk into a farm level Positive Mathematical Programming (PMP) model. The model presents some innovations with respect to the previous literature and estimates simultaneously the resource shadow prices, the farm non-linear cost function and a farm-specific coefficient of absolute risk aversion. The proposed model has been applied to three farm samples and the estimation results confirm the calibration ability of the model and show values for risk aversion coefficients consistent with the literature. Finally different scenarios have been simulated to test the potential role of an AES as risk management tool under different scenarios of crop price volatility.
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Risikoprädiktion für sehr frühen Reinfarkt, Tod und Progression nach ischämischem Schlaganfall / Risk prediction of very early recurrence, death and progression after acute ischaemic strokeMaier, Ilko 20 January 2014 (has links)
No description available.
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The relationship between strength, power and speed measures and playing ability in premier level competition rugby forwardsBramley, Wesley Joel January 2006 (has links)
Physical tasks such as scrummaging, rucking and mauling are highly specific to rugby and also place unique physiological demands on the different playing positions within the forwards. Traditionally, the recruitment and development of talented rugby union players has focused on the assessment of motor skills and game intelligence aspects of performance, with less emphasis placed on the specific physiological requirements of playing positions in rugby. The purpose of this investigation was to measure the position-specific strength, speed and power characteristics of Premier rugby forwards in order (1) to determine whether any differences existed in the physiological characteristics of the different forward playing positions (prop, lock and loose forwards) and (2) to investigate the relationship between these physiological characteristics and coaches evaluations of football playing ability. Twenty-two male Premier level competition rugby forwards, consisting of eight prop forwards, five lock forwards and nine loose-forwards participated in the study. The Grunt 3000, a rugby specific force testing device was utilised to measure the static and dynamic horizontal strength during simulated scrummaging and rucking/mauling movements. Sprint times relating to acceleration ability (0 -10m, 0-20m) and maximum running speed (20 - 40m) were measured during a 40m sprint running test. In addition, force, power and displacement characteristics of a countermovement vertical jump were calculated from trials performed on a force plate. Also, player performance skill and physical capacity scores were determined independently by experienced coaches who assessed them based on their performances during the season. One-way analysis of variance and effect size statistics evaluated differences in the measured variables between forward playing positions and linear regression analysis evaluated the relationship between the coaches' scores of player performance skill and physical capacity and game specific measures of strength speed and power. Since there were no statistical significant differences between forward groups for horizontal force and countermovement jump variables and these analyses lacked statistical power, an effect size statistic was used to establish trends for differences in force and CMJ variables between the groups. There were moderate effect size differences between groups for horizontal impact force with prop and lock forwards producing 17.7% and 12.8% more force than the loose forwards respectively. No clear differences were apparent between forward positional groups for mean dynamic horizontal force and countermovement jump displacement of the centre of gravity. A significant difference (p =0.049) was shown between forward positional groups over the 0-40m sprint distance. Also, moderate effect size differences between pairs of groups were evident in 0-10m, 0-20m, 20-40m sprint times with both loose forwards and lock forwards on average, 6% faster than the prop forwards. A backward linear regression analysis revealed that the single best predictor of coaches' physical capacity and performance skill scores was the 20 - 40m sprint performance, accounting for 28% of the variance in player's physical capacity scores and 29% of the variance in player's performance skill scores. Whole-body horizontal static strength and impact strength in prop forwards and dynamic horizontal strength (relative to body mass) and sprint acceleration ability in loose forwards represent key factors for consideration when selecting forward players to these positions in the Premier rugby competition. The vertical jumping ability of all forward positional groups needs to be confirmed in a future study utilising a line-out specific countermovement jump test (free use of arm swing and line-out lifters in the jump) on a force plate. Monitoring of performance in rugby forwards should include an acceleration sprint test (0-10m) as this is specific to the sprinting patterns of forward players during a game, and maximum sprinting speed test (20-40m) as this test has the ability to discriminate between skilled and less-skilled rugby union forwards.
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Aplikace vybrané metody identifikace účetního podvodu v podmínkách vybraného podniku / Application of selected methods of identifying accounting fraud in terms of the selected companySTAŇKOVÁ, Naděžda January 2016 (has links)
The aim of my diploma thesis was the application of the selected method of identifying accounting fraud in setting of chosen company. In the first part of this work were used methods based on the comparison of data chosen company with the data of competitive companies in the same industry or with the data of industry. I compare the return on equity (ROE), return on assets (ROA), Daily income and balance of accounts receivable, profit margin. In the next part of this work were used special methods to identify accounting fraud. I used methods Beneish M-score model, cash realization ratio, Jones nondiscretionary accruals. As an additional analysis, I used the bankruptcy Altman Z-score model. In conclusion, I compared the risks identified possible manipulation of financial statements for all tests and analyzes. All performed tests and analyzes in aggregate have identified this risk as low. Yet some of them pointed to further more detailed research in revenues, margins and setting transfer prices.
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Grafické partitury jako cesta ke skutečnosti. Ukázka "komplexního realismu" v tvorbě československých umělců 60. a 70. let 20. století v kontextu mezinárodního hnutí experimentální tvorby. / Graphic Scores as a Way towards Reality. Example of "Complex Realism" in the Works of Czechoslovak Artists of the 1960s and 1970s within the Context of International Experimental Creation Movement.Hlaváčková, Jitka January 2015 (has links)
The present work deals, from a general point of view, with the research of methods of depiction. In particular, it focuses on the phenomenon of graphical or visual scores in the former Czechoslovakia within the context of experimental creation movement of the early 1960s. It tries to discover the historical and also immediate social and artistic sources of their existence. It finds them in the need to express the primary (empiric) sensual experience, free from any formal assumptions stemming out of the traditional ways of depiction. The text points out mainly to the multidisciplinary qualities of the studied phenomenon defining "intermediality" as a "realistic tendency" and trying to substantiate both the origins and importance of intermediality within the artistic context of second half of 20th century by means of reflexion of older sources from the fields of history of art, music, philosophy (T. W. Adorno), sociology (M. McLuhan), semiotics (N. Goodman), as well as through original analysis of material. The work further investigates into the parallels within the evolution of visual art and music, mainly of the early avant-garde period (Dadaism, birth of conceptual art and complex work of the Bauhaus circle). It reflexes on the contemporary, and mostly foreign, context of the existence of the...
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Modèles d'appariement du greffon à son hôte, gestion de file d'attente et évaluation du bénéfice de survie en transplantation hépatique à partir de la base nationale de l'Agence de la Biomédecine. / Liver transplantation graft-to-recipient matching models, queue management and evaluation of the survival benefit : study based on the Agency of Biomedicine national databaseWinter, Audrey 28 September 2017 (has links)
La transplantation hépatique (TH) est la seule intervention possible en cas de défaillance hépatique terminale. Une des limitations majeures à la TH est la pénurie d'organes. Pour pallier ce problème, les critères de sélection des donneurs ont été élargis avec l'utilisation de foie de donneurs dits à "critères étendus" (extended criteria donor (ECD)). Cependant, il n'existe pas de définition univoque de ces foies ECD. Un score donneur américain a donc été mis en place : le Donor Risk Index (DRI), pour qualifier ces greffons. Mais à qui doit-on donner ces greffons "limites"? En effet, une utilisation appropriée des greffons ECD pourrait réduire la pénurie d'organes. Le but de cette thèse est d'établir un nouveau système d'allocation des greffons qui permettrait à chaque greffon d'être transplanté au candidat dont la transplantation permettra le plus grand bénéfice de survie et d'évaluer l'appariement entre donneurs et receveurs en tenant compte des greffons ECD.La première étape a consisté à effectuer une validation externe du DRI ainsi que du score qui en découle : l'Eurotransplant-DRI. Toutefois la calibration et la discrimination n'étaient pas maintenus dans la base française. Un nouveau score pronostique donneur a donc été élaboré : le DRI-Optimatch, à l'aide d'un modèle de Cox donneur ajusté sur les covariables receveur. Le modèle a été validé par bootstrap avec correction de la performance par l'optimisme.La seconde étape consista à explorer l'appariement entre donneur et receveur afin d'attribuer les greffons ECD de manière optimale. Il a été tenu compte des critères donneurs et receveurs, tels qu'évalués par le DRI-Optimatch et par le MELD (Model for End-stage Liver Disease, score pronostique receveur), respectivement. La méthode de stratification séquentielle retenue s'inspire du principe de l'essai contrôlé randomisé. Nous avons alors estimé, à l'aide de rapport de risques, quel bénéfice de survie un patient donné (repéré à l'aide du MELD) pourrait avoir avec un greffon donné (repéré à l'aide du DRI-Optimatch) en le comparant avec le groupe de référence composé des patients (même MELD), éligibles à la greffe, restés sur liste dans l'attente d'un meilleur greffon (DRI-Optimatch plus petit).Dans une troisième étape, nous avons développé un système d'allocation basé sur le bénéfice de survie alliant deux grands principes dans l'allocation de greffons; l'urgence et l'utilité. Dans ce type de système, un greffon alloué est attribué au patient avec la plus grande différence entre la durée de vie post-transplantation prédite et la durée estimée sur la liste d'attente pour un donneur spécifique. Ce modèle est principalement basé sur deux modèles de Cox : un pré-greffe et un post-greffe. Dans ces deux modèles l'évènement d'intérêt étant le décès du patient, pour le modèle pré-greffe, la censure dépendante a été prise en compte. En effet, sur liste d'attente le décès est bien souvent censuré par un autre évènement : la transplantation. Une méthode dérivée de l'Inverse Probability of Censoring Weighting a été utilisée pour pondérer chaque observation. De plus, données longitudinales et données de survie ont aussi été utilisées. Un modèle "en partie conditionnel", permettant d'estimer l'effet de covariables dépendantes du temps en présence de censure dépendante, a été utilisé pour modéliser la survie pré-greffe.Après avoir développé un nouveau système d'allocation, la quatrième et dernière étape, nous a permis de l'évaluer à travers de simulation d'évènement discret ou DES : Discret Event Simulation. / Liver transplantation (LT) is the only life-saving procedure for liver failure. One of the major impediments to LT is the shortage of organs. To decrease organ shortage, donor selection criteria were expanded with the use of extended criteria donor (ECD). However, an unequivocal definition of these ECD livers was not available. To address this issue, an American Donor Risk Index (DRI) was developed to qualify those grafts. But to whom should those ECD grafts be given? Indeed, a proper use of ECD grafts could reduce organ shortage. The aim of this thesis is to establish a new graft allocation system which would allow each graft to be transplanted in the candidate whose LT will allow the greatest survival benefit; and to evaluate the matching between donors and recipients taking into account ECD grafts.The first step was the external validation of the DRI as well as the resultant Eurotransplant-DRI score. However, calibration and discrimination were not maintained on the French database. A new prognostic donor score: the DRI-Optimatch was then developed using a Cox donor model with adjustment on recipient covariates. The model was validated by bootstrapping with correction of the performance by the optimism.The second step was to explore the matching between donors and recipients in order to allocate ECD grafts optimally. Consideration should be given to the donor and recipient criteria, as assessed by the DRI-Optimatch and the Model for End-stage Liver Disease (MELD), respectively. The sequential stratification method retained is based on the randomized controlled trial principle. We then estimated, through hazard ratios, the survival benefit for different categories of MELD and DRI-Optimatch compared against the group of candidates remaining on the wait list (WL) and waiting for a transplant with a graft of better quality (lower DRI-Optimatch).In the third step, we have developed an allocation system based on survival benefit combining the two main principles in graft allocation; urgency and utility. In this system, a graft is allocated to the patient with the greatest difference between the predicted post-transplant life and the estimated waiting time for a specific donor. This model is mainly based on two Cox models: pre-LT and post-LT. In these two models the event of interest being the death of the patient, for the pre-graft model, the dependent censoring was taken into account. Indeed, on the WL, death is often censored by another event: transplantation. A method derived from Inverse Probability of Censoring Weighting was used to weight each observation. In addition, longitudinal data and survival data were also used. A partly conditional model, to estimate the effect of time-dependent covariates in the presence of dependent censoring, was therefore used for the pre-LT model.After developing a new allocation system, the fourth and final step was to evaluate it through Discrete Event Simulation (DES).
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Konkursprognostisering : En studie om nyckeltalens betydelse vid konkurser i de svenska byggföretagenBasoda, Muhammed, Celik, Azime January 2018 (has links)
Bakgrund och problemdiskussion: Idag är konkurser ett problem då många företag försätts i konkurs samt att de bidrar till konsekvenser som påverkar hela samhället. Byggföretag är hårt drabbade och det finns olika tillvägagångssätt, bland annat att genom olika modeller och nyckeltal, för att beräkna konkurser i förväg och ta åtgärder. Syfte: Syftet med studien är att jämföra och analysera fem olika konkursprognostiseringsmodeller och dess nyckeltal i de svenska byggföretagen, för att se om någon eller några modeller är tillämpbara. Syftet med studien är vidare att jämföra våra resultat med resultatet från den litauiska studien och se om vi får ett liknande resultat. Metod: Studien har använt ett kvantitativt tillvägagångssätt där data har samlats in från årsredovisningar för att sedan tillämpas i fem konkursprognostiseringsmodeller. Vidare har nyckeltalen granskats bland annat utifrån en regressionsanalys. Resultat och slutsats: Ingen av de fem modellerna är tillämpbara i de svenska byggföretagen då ingen av påvisar en tillräckligt hög träffsäkerhet som anses pålitlig. Med hjälp av nyckeltal kan man till hög grad säga hur väl ett företag mår och därför till viss sannolikhet säga huruvida företaget kommer gå i konkurs. / Background: When companies go bankrupt and they contribute to consequences that affect the entire society from different aspect. The construction sector is very affected line of business but there are different approaches for calculating bankruptcies in advance and measuring how well a business is. Purpose: The purpose of this study is to compare and analyze five different bankruptcy prediction models and their financial ratios in Swedish construction sector, to see if any or some models are applicable. Furthermore, the purpose of the study is also to compare our results with the results from the Lithuanian study and see if we get a similar result. Method: The study has used a quantitative approach where data has been collected from the companies’ annual financial reports and then applied in five bankruptcy prediction models. Results and conclusion: None of the five models are applicable in Swedish construction sector, as none of them shows high accuracy which is considered reliable.
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Genomsökning av filsystem för att hitta personuppgifter : Med Linear chain conditional random field och Regular expressionAfram, Gabriel January 2018 (has links)
The new General Data Protection Regulation (GDPR) Act will apply to all companies within the European Union after 25 May. This means stricter legal requirements for companies that in some way store personal data. The goal of this project is therefore to make it easier for companies to meet the new legal requirements. This by creating a tool that searches file systems and visually shows the user in a graphical user interface which files contain personal data. The tool uses Named entity recognition with the Linear chain conditional random field algorithm which is a type of supervised learning method in machine learning. This algorithm is used in the project to find names and addresses in files. The different models are trained with different parameters and the training is done using the stanford NER library in Java. The models are tested by a test file containing 45,000 words where the models themselves can predict all classes to the words in the file. The models are then compared with each other using the measurements of precision, recall and F-score to find the best model. The tool also uses Regular Expression to find emails, IP numbers, and social security numbers. The result of the final machine learning model shows that it does not find all names and addresses, but that can be improved by increasing exercise data. However, this is something that requires a more powerful computer than the one used in this project. An analysis of how the Swedish language is built would also need to be done to apply the most appropriate parameters for the training of the model. / Den nya lagen General data protection regulation (GDPR) började gälla för alla företag inom Europeiska unionen efter den 25 maj. Detta innebär att det blir strängare lagkrav för företag som på något sätt lagrar personuppgifter. Målet med detta projekt är därför att underlätta för företag att uppfylla de nya lagkraven. Detta genom att skapa ett verktyg som söker igenom filsystem och visuellt visar användaren i ett grafiskt användargränssnitt vilka filer som innehåller personuppgifter. Verktyget använder Named Entity Recognition med algoritmen Linear Chain Conditional Random Field som är en typ av ”supervised” learning metod inom maskininlärning. Denna algoritm används för att hitta namn och adresser i filer. De olika modellerna tränas med olika parametrar och träningen sker med hjälp av biblioteket Stanford NER i Java. Modellerna testas genom en testfil som innehåller 45 000 ord där modellerna själva får förutspå alla klasser till orden i filen. Modellerna jämförs sedan med varandra med hjälp av mätvärdena precision, recall och F-score för att hitta den bästa modellen. Verktyget använder även Regular expression för att hitta e- mails, IP-nummer och personnummer. Resultatet på den slutgiltiga maskininlärnings modellen visar att den inte hittar alla namn och adresser men att det är något som kan förbättras genom att öka träningsdata. Detta är dock något som kräver en kraftfullare dator än den som användes i detta projekt. En undersökning på hur det svenska språket är uppbyggt skulle även också behöva göras för att använda de lämpligaste parametrarna vid träningen av modellen.
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Estudo de prevalência de disfunção tireoidiana em pacientes com diabetes mellitus acompanhados no ambulatório de diabetes do Hospital Universitário Pedro Ernesto / Study of the thyroid dysfunction prevalence in patients with diabetes mellitus treated in ambulatory diabetes of the Hospital Universitário Pedro ErnestoCátia Cristina Silva Sousa Vergara Palma 25 March 2013 (has links)
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / O diabetes mellitus(DM) e as disfunções tireoidianas(DT) são as duas desordens endocrinológicas mais comuns na prática clínica. A DT não reconhecida pode interferir no controle metabólico e adicionar mais risco a um cenário predisponente à doença cardiovascular. O objetivo deste estudo foi avaliar a prevalência da DT em pacientes com diabetes mellitus tipo 1 e tipo 2 (DM1 e DM2) e avaliar o risco cardiovascular em pacientes com DM2 com e sem DT utilizando parâmetros clínicos e laboratoriais. Trata-se de um estudo observacional de corte transversal. Foram avaliados 304 pacientes com DM2 e 82 pacientes com DM1. Os pacientes foram submetidos a um inquérito clínico-demográfico e avaliação laboratorial para determinação do perfil lipídico, glicídico e da função tireoidiana. Os pacientes com DM2 tiveram seus escores de risco cardiovascular em 10 anos determinados pelas equações de Framingham e do UKPDS risk engine. A frequência de disfunção tireoidiana entre os 386 pacientes foi de 14,7%, sendo de 13% nos que não possuíam disfunção prévia. A disfunção mais frequente encontrada foi de hipotireoidismo subclínico, com 13% no DM1 e de 12% no DM2. A prevalência de anticorpos anti-tireoperoxidase (TPO) positivos foi de 10,8%, sendo de14,6% em pacientes com DM1.Foram diagnosticados 44 (11,2%) novos casos de disfunção tireoidiana em pacientes que negavam ou desconheciam terem DT prévia.Destes novos casos, 12,8% em DM1 e 13,1% em DM2.Dos 49 pacientes com DT prévia, 50% dos DM1e 76% dos DM2 estavam compensados. Não foi observada diferença entre as médias do escore de risco de Framingham entre os pacientes DM2 com eutireoidismo e com hipotireoidismo subclínico. Observou-se uma associação entre o hipotireoidismo subclínico e risco cardiovascular nos pacientes com DM2 demonstrado pela diferença estatisticamente significativa entre as médias do escore UKPDS para doença coronariana não-fatal e fatal, acidente vascular cerebral fatal entre os dois grupos (p=0,007; 0,005;0,027 respectivamente). As demais funções tireodianas (hipotireoidismo clínico, hipertireoidismo clínico e subclínico) encontradas não foram analisadas devido ao pequeno número de pacientes em cada grupo.Concluímos que o rastreio da doença tireoidiana entre os pacientes com diabetes mellitus deve ser realizado rotineiramente considerando-se a prevalência de novos casos de DT diagnosticados e o fato de que os pacientes com DM2 e com hipotireoidismo subclínico avaliados possuírem um risco cardiovascular maior. Todavia, concluímos que estudos prospectivos e com maior número de pacientes são necessários para o esclarecimento do impacto da doença tireoidiana no risco cardiovascular do paciente com DM. / Diabetes mellitus and thyroid dysfunction (TD) are the two most common endocrine disorders in clinical practice. The unrecognized TD may adversely affect the metabolic control and add more risk to an already predisposing scenario for cardiovascular diseases. The objective of this study was to evaluate the prevalence of TD in patients with type 1 and type 2 diabetes mellitus (T1DM and T2DM) and to evaluate the cardiovascular risk of patients with T2DM with and without thyroid dysfunction using clinical and laboratory parameters. This is an observational cross-sectional study. We evaluated 304 patients with T2DM and 82 patients with T1DM. The patients underwent a clinical-demographic survey and laboratory evaluation to determine the lipid and glycemic profile and thyroid function. Patients with T2DM had their 10 years cardiovascular risk scores determined by Framingham equations and the UKPDS risk engine. The frequency of TD among the 386 patients was 14.7% and 13% who denied previous TD. The most frequently TD was subclinical hypothyroidism, in 13% of patients with T1DM and in 12% of patients with T2DM.The prevalence of anti-TPO antibodies was 10.8%, being more frequently among patients with T1DM (14.6%). Forty-four (11.2%) new cases of TD were diagnosed during the study in patients who denied or were unaware of this clinical condition. Of the 49 patients with prior TD,50% of the T1DM and 76% of T2DM were compensated. No differencies were observed between the mean scores of the Framingham risk among patients with T2DM who had normal thyroid function compared to those with subclinical hypothyroidism. An association between subclinical hypothyroidism and cardiovascular risk in T2DM patients was found by statistically significant difference between the mean UKPDS scores for non-fatal and fatal CHD and fatal stroke between the two groups (p = 0,007;0,005;0027; respectively). The other TD (clinical hypothyroidism, clinical and subclinical hyperthyroidism) found were not analyzed due to the small number of patients in each group.We conclude that screening for thyroid disease among patients with diabetes mellitus should be routinely performed considering the prevalence of new cases diagnosed and the fact that patients with DM2 and subclinical hypothyroidism evaluated had a higher cardiovascular risk. However, prospective studies and with more patients are warranted to determine the impact of thyroid dysfunction in the cardiovascular risk of patients with diabetes.
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