MIMIC Models, Cointegration and Error Correction: An Application to the French Shadow Economy

The analysis of economic loss attributed to the shadow economy has attracted much attention in recent years by both academics and policy makers. Often, multiple indicators multiple causes (MIMIC) models are applied to time series data estimating the size and development of the shadow economy for a particular country. This type of model derives information about the relationship between cause and indicator variables and a latent variable, here the shadow economy, from covariance structures. As most macroeconomic variables do not satisfy stationarity, long run information is lost when employing first differences. Arguably, this shortcoming is rooted in the lack of an appropriate MIMIC model which considers cointegration among variables. This paper develops a MIMIC model which estimates the cointegration equilibrium relationship and the error correction short run dynamics, thereby retaining information for the long run. Using France as our example, we demonstrate that this approach allows researchers to obtain more accurate estimates about the size and development of the shadow economy.shadow economy, tax burden, regulation, unemployment, cointegration, error correction models, MIMIC models

Decentralization and the Shadow Economy: Oates Meets Allingham-Sandmo

This paper studies the impact of decentralization on the shadow economy. We argue that decentralization may decrease the size of the shadow economy mainly through two transmission channels: (1) Decentralization enhancing public sector efficiency (efficiency effect), and (2) decentralization reducing the distance between bureaucrats and economic agents, which increases the probability of detection of shadow economic activities (deterrence effect). Using various measures of fiscal, political and government employment decentralization in a cross-section of countries, we find the deterrence effect to be of more importance. The deterrence effect is stronger, the lower the degree of institutional quality. Remarkably, we find no robust evidence of the efficiency effect.decentralization, shadow economy

Size and Development of the Shadow Economy and of Do-it-yourself Activities in Germany

This paper presents the first MIMIC (multiple indicator multiple causes) model estimate of the size and development of the shadow economy and of do-it-yourself (DIY) activities in Germany from 1970 to 2005. By 2005, they reached a level of about 17% and 4.94%. While the shadow economy has regularly increased over the years, DIY activities – though quite sizeable – have remained more or less constant since the early 1990s. The driving forces for the shadow economy are regulation and tax burden whereas for DIY activities, the level of unemployment is the main factor.shadow economy, do-it-yourself activities, tax burden, regulation, domestic currency in circulation, unemployment, MIMIC models

Informal Economic Activities

The dissertation “Informal Economic Activities” takes a comprehensive approach to the informal economy by studying traditional shadow economic activities, household DIY activities, and the smuggling of illegal and legal goods. Chapter 2 analyzes shadow economic and DIY activities and presents a dual estimation for the development of both types of informal economic activities in Germany from 1970 to 2005. It also considers the impact of German reunification on shadow economic and DIY activities and employs a proper estimate of domestic currency in circulation within Germany as an indicator variable for the shadow economy. Chapter 3 studies an informal economic activity that has attracted much attention recently: legal goods smuggling, or the illegal trade of otherwise legal goods. The main channel of this type of smuggling is the falsification of trade documents. By reporting false amounts of exports and/or imports to authorities smugglers, or trade misinvoicers, seek to avoid paying taxes and/or tariffs. Chapter 4 widens the analysis of smuggling to the smuggling of illegal goods and studies the smuggling of legal and illegal goods across the U.S.-Mexico border in order to improve the understanding of illegal trade. Studying the U.S.-Mexican case is particularly interesting as most illegal drugs and immigrants enter the United States via the Mexican border. The empirical analyses in the dissertation “Informal Economic Activities” are based on structural equation models (SEMs). The results demonstrate that the informal economy is significant and that growth of the informal economy is not exclusive to developing countries, although it is a more serious problem in these countries. Moreover, although the informal economy covers a wide range of rather diverse economic activities, the dissertation works out that a few similarities exist. These are important, especially for policymakers, in first understanding what drives informal economic activities and second designing appropriate policies to deter them

Combined U-Pb and Lu-Hf isotope analyses by laser ablation MC-ICP-MS : methodology and applications

O sistema isotópico Lutécio-Hafnio representa uma das ferramentas mais recentes e poderosas para estudos isotópicos e geocronológicos. Análises combinadas in situ de U-Pb e Lu-Hf sobre zircão pelo LA-MC-ICP-MS permitem caracterizar isotopicamente o magma onde ele cristalizou, fornecendo valiosas informações para estudos de proveniência de sedimento e de evolução crustal. Nesse trabalho descrevemos a sistemática de Lu-Hf pelo LA-MC-ICP-MS implantada no laboratório de Geocronologia da Universidade de Brasília e reportamos os resultados obtidos de repetidas análises de três padrões de zircão: GJ-1 = 0.282022 ± 11 (2SD, n=56), Temora 2 = 0.282693 ± 14 (2SD, n=25) and UQ-Z = 0.282127 ± 33 (2SD, n=11). Foi também caracterizada arazão isotópica 176Hf/177Hf(0.282352 ± 22, 2SD, n=14) de um zircão usado como padrão interno do laboratório. Como aplicação geológica, analisamos dois zircões complexos selecionados a partir de uma amostra de migmatito da Província de Borborema, NE do Brasil. Sobre a base dos dados U-Pb e Lu-Hf foram identificados em ambos os zircões dois eventos de cristalização. Um evento mais antigo de 2.05 Ga nos núcleos herdados, representa um evento magmático Paleoproterozoico bem conhecido na Província Borborema. Um segundo evento de ~ 575 Ma, reconhecido nas bordas, representa um evento magmático-metamórfico Neoproterozóico (Brasiliano). ________________________________________________________________________________________ ABSTRACTThe Lutetium-Hafnium isotopic system represents one of the most innovative and powerful tools for geochronology and isotopic studies. Combined U-Pb and Lu-Hf in situ analyses on zircon by LA-MC-ICP-MS permit to characterize isotopically the host magma from which it crystallized furnishing significant information for sediment provenance and crustal evolution studies. In this paper e describe the Lu-Hf systematic by LA-MC-ICP-MS developed in the laboratory of Geochronology of the University of Brasilia and report the results obtained by repeated analyses of 176Hf/177Hf isotopic ratio of three zircon standards: GJ-1 = 0.282022 ± 11 (n=56), Temora 2 = 0.282693 ± 14 (n=25) and UQZ = 0.282127 ± 33 (n=11). The 176Hf/177Hf ratio (0.282352 ± 22, n=14) of gem quality zircon used as in-house standard have been also characterized. As a geological application, we analyzed two complex zircons selected from a migmatitic rocks from the Borborema Province, NE Brazil. On the basis of U-Pb and Lu-Hf data, two main crystallization events have been identified in both studied zircons. An older event at ca. 2.05 Ga recognized in the inherited cores represents a well-characterized paleoproterozoic magmatic event that affected the whole Borborema Province. A second crystallization event at ~ 575 Ma, recognized at the rims, represents a Neoproterozoic (Brazilian) high grade metamorphic-magmatic event

Precambrian to modern manganese mineralization: changes in ore type and depositional environment

Manganese mineralization is diverse in occurrence, origin, mineralogy and geochemistry. These variations reflect differences in the processes of formation and depositional environments, which in turn are a response to changes in the land-ocean-atmosphere system over geological time. As such, manganese deposits can act as markers of major events in the dynamic evolution of the Earth's surface. Modern manganese accumulations provide insights into key factors controlling manganese deposition that cannot readily be determined from examination of ancient ores. A knowledge of oceanic currents, ocean chemistry or small-scale variations in physicochemical patterns of recent basins, for example, may extend our understanding of depositional processes in the past. Equally, the study of Precambrian deposits not only elucidates ancient mechanisms of manganese metallogenesis, but also helps to unravel the impact of comprehensive environmental changes on metal deposition on a scale not realized in younger geological times

High spatial resolution analysis of Pb and U isotopes for geochronology by laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS)

A determinação de idades através do decaimento dos isótopos radioativos 235U e 238U para os isótopos radiogênicos 207Pb e 206Pb, respectivamente, utilizando o mineral zircão (ZrSiO4), é amplamente aplicada para decifrar processos geológicos. Um novo método tem sido desenvolvido nos últimos anos, a ablação a laser multi-coletor espectrometria de massas com plasma indutivamente acoplado (LA-MC-ICP-MS), superando o laborioso trabalho anteriormente necessário em outros métodos, na preparação de amostras, e permite obtenção de razões isotópicas com alta resolução espacial de micrômetros. O presente estudo descreve os procedimentos analíticos e os métodos usados na redução de dados que estão sendo aplicados no Laboratório de Geocronologia da Universidade de Brasília. Explora-se a precisão e exatidão do método através da análise de três padrões internacionais de zircão. Observa-se uma precisão entre 1,9 a 3,7% (2σ desvio padrão) e uma exatidão de 0,6 a 3,8% (2σ desvio padrão) para as razões isotópicas de Pb e U dos padrões. Também foram obtidas idades pelo método LA-ICP-MS de duas amostras de zircões naturais, que já foram datadas anteriormente por outros métodos analíticos. A comparação dos resultados mostra uma boa conformidade das idades obtidas, dentro dos limites de erro.Os dados demonstram o grande potencial do método analítico para análises isotópicas rápidas, precisas e exatas de U-Pb, numa escala de micrômetros. ________________________________________________________________________________________ ABSTRACTAge determinations using the 235U and 238U radioactive decay series to the daughter isotopes 207Pb and 206Pb, respectively, using the mineral zircon (ZrSiO4), are widely used to decipher geological processes. A new method developed in the last couple of years, the laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS), overcomes previous laborious sample preparation, and yields isotopic ratios and age data with a high spatial resolution of ten of microns. The present study describes the analytical set-up and data reduction process as presently applied at the Laboratory for Geochronology of the University of Brasília. It explores the precision and accuracy of the method by cross-analysing three international zircon standards. We arrive at a precision of 1.9 to 3.7% (2σ SD) and an accuracy of 0.6 to 3.8% (2σ SD) for and U isotopic ratios of the standards. We also apply the method to two natural zircon samples, which have previously been dated by other analytical methods. A comparison of the results show a good conformity of the age data,being whitin the error limits. The data demonstrate the great analytical potential of the method for rapid, precise and accurate U-Pb isotopic analyses on the micron scale

Systematic review of the clinical effectiveness of biomarkers as cancer screening test offered as self-pay service in Austria and Germany [Abstract]

Background: Individual health services (IGeL) are medical self-pay services that are not under the liability of the German statutory health insurance. Up to 14% of IGeL are blood or laboratory and cancer screening tests, which are offered to asymptomatic individuals [1]. The aim was to investigate the clinical effectiveness of eleven biomarkers that are the most often offered biomarkers for cancer screening by physicians and laboratories on the internet in Germany (i.e., AFP, CA125, CA15-3, CA19-9, CEA, Cyfra21-1, β-HCG, NMP22, M2-PK, NSE and PCA3). Research Question: What is the benefit-harm-balance regarding patient relevant outcomes (mortality, morbidity, quality of life) for using these biomarkers as cancer screening test in comparison to usual care? Methods: Firstly, searches for Health Technology Assessment (HTA) reports and systematic reviews (SR) were performed in three different databases in spring 2012. Secondly, randomized controlled trials (RCT) that were published after the end of the research period of the most recent included secondary study were searched. We included publications in English or German which compared cancer screening with one of these biomarkers in asymptomatic persons to unscreened controls. References were independently screened by two reviewers. One reviewer extracted relevant characteristics from full text and evaluated the quality of included studies. Results: Five HTA or SR dealing with CA125 (4) or NMP22 (1) and 2 RCTs (CA125) were included. For ten biomarkers, incl. NMP22, no direct evidence on patient relevant outcomes was available. One RCT combining CA125 and vaginal ultrasound for ovarian cancer screening provided results of interest [2]. Screening compared with usual care did not reduce ovarian cancer mortality (RR, 1.18; 95% CI, 0.82-1.71) [2]. Harms occurred through overdiagnosis and false-positive results, e.g., 20.6 complications occurred per 100 surgical procedures in women who underwent surgery after a false-positive result [2]. About 4.5 surgeries were performed per one case of invasive cancer identified through CA125 screening [3]. Conclusion: While ovarian cancer screening with CA125 showed no survival benefit, false-positive tests, overdiagnosis and -treatment resulted in harm. For ten biomarkers no sufficient evidence was available. When IGeL are offered, patients should get comprehensive information about the lack of evidence on patient-relevant outcomes and potential harm caused by biomarker screening

Krise der Wirtschaftswissenschaften: Braucht die VWL eine Neuausrichtung?

In den vergangenen Jahren hat sich das Verständnis der Volkswirtschaftslehre gewandelt. Bis in die siebziger Jahre dominierte die Wirtschaftspolitik, die sich auch als Berater außerhalb der Universitäten verstand. Dann schwappte von den USA die Mathematisierung der Volkswirtschaftslehre nach Deutschland über und ergriff ganze Universitäten. Das Fach Wirtschaftspolitik wurde ins Abseits gedrängt. Welchen Beitrag leistet die moderne Volkswirtschaftslehre zum Verständnis aktueller wirtschaftspolitischer Probleme? Lutz Arnold, Universität Regensburg, stellt fest, dass die VWL zwar ebenso wenig gegen Fehlentwicklungen gefeit sei wie andere wissenschaftliche Disziplinen. Aus den Tatsachen, dass nur ein kleiner Teil der aktuellen Forschung in den wirtschaftspolitisch relevanten Lehrbüchern zu finden sei und dass die Ökonomen die aktuelle Wirtschafts- und Finanzkrise nicht prognostizierten, lasse sich aber nicht auf eine Krise der VWL schließen. Olaf Hübler, Universität Hannover, weist den Vorwurf, die Ökonomik könne keinen relevanten Beitrag zur Vorhersage, Erklärung und Beseitigung der Krise liefern, da die ökonomische Theorie zu stark mathematisiert sei und menschliches Verhalten nur mangelhaft berücksichtige, zurück. Man solle weiter auf dem eingeschlagenen Weg vorangehen. Für Peter Oberender, Universität Bayreuth, ist es wichtig, die Internationalität der deutschen Volkswirtschaftslehre zu stärken. Gleichwohl könne eine Fundierung ordnungsökonomischer Analyse in den Kontext der ideengeschichtlichen Entwicklung hilfreiche Orientierungspunkte für die Auseinandersetzung mit den Grenzbereichen der ökonomischen Analyse geben. Und Alexander Karmann und Andreas Bühn, Technische Universität Dresden, fordern, dass die begonnene Öffnung der volkswirtschaftlichen Forschung in Deutschland konsequent fortgeführt werden solle.Wirtschaftsstudium, Volkswirtschaft, Wirtschaftswissenschaftliche Hochschule, Krise, Deutschland

A systematic review on the effectiveness of implementation strategies to postpone elective caesarean sections to ≥ 39 + (0-6) weeks of gestation

BACKGROUND Caesarean sections often have no urgent indication and are electively planned. Research showed that elective caesarean section should not be performed until 39 + (0-6) weeks of gestation to ensure best neonatal and maternal health if there are no contraindications. This was recommended by various guidelines published in the last two decades. With this systematic review, we are looking for implementation strategies trying to implement these recommendations to reduce elective caesarean section before 39 + (0-6) weeks of gestation. METHODS We performed a systematic literature search in MEDLINE, EMBASE, CENTRAL, and CINAHL on 3rd of March 2021. We included studies that assessed implementation strategies aiming to postpone elective caesarean section to ≥ 39 + (0-6) weeks of gestation. There were no restrictions regarding the type of implementation strategy or reasons for elective caesarean section. Our primary outcome was the rate of elective caesarean sections before 39 + (0-6) weeks of gestation. We used the ROBINS-I Tool for the assessment of risk of bias. We did a narrative analysis of the results. RESULTS We included 10 studies, of which were 2 interrupted time series and 8 before-after studies, covering 205,954 elective caesarean births. All studies included various types of implementation strategies. All implementation strategies showed success in decreasing the rate of elective caesarean sections performed < 39 + (0-6) weeks of gestation. Risk difference differed from - 7 (95% CI - 8; - 7) to - 45 (95% CI - 51; - 31). Three studies reported the rate of neonatal intensive care unit admission and showed little reduction. CONCLUSION This systematic review shows that all presented implementation strategies to reduce elective caesarean section before 39 + (0-6) weeks of gestation are effective. Reduction rates differ widely and it remains unclear which strategy is most successful. Strategies used locally in one hospital seem a little more effective. Included studies are either before-after studies (8) or interrupted time series (2) and the overall quality of the evidence is rather low. However, most of the studies identified specific barriers in the implementation process. For planning an implementation strategy to reduce elective caesarean section before 39 + (0-6) weeks of gestation, it is necessary to consider specific barriers and facilitators and take all obstetric personal into account. SYSTEMATIC REVIEW REGISTRATION PROSPERO CRD42017078231