A note on GMM-estimation of probit models with endogenous regressors

Dagenais (1999) and Lucchetti (2002) have demonstrated that the naive GMM estimator of Grogger (1990) for the probit model with an endogenous regressor is not consistent. This paper completes their discussion by explaining the reason for the inconsistency and presenting a natural solution. Furthermore, the resulting GMM estimator is analyzed in a Monte-Carlo simulation and compared with alternative estimators.generalized method of moments, probit model, endogenous regressor

A Simple Representation of the Bera-Jarque-Lee Test for Probit Models

The inference in probit models relies on the assumption of normality. However, tests of this assumption are not implemented in standard econometric software. Therefore, the paper presents a simple representation of the Bera-Jarque-Lee test, that does not require any matrix algebra. Furthermore, the representation is used to compare the Bera-Jarque- Lee test with the RESET-type test proposed by Papke and Wooldridge (1996).probit model, Lagrange multiplier test, normality assumption, artificial regression

The Impact of Skills on Remigration Flows

More than ten years after the seminal paper by Borjas and Bratsberg (1996) modeling the impact of skills on remigration the empirical evidence on that theory is still mixed. Our paper is to shed light on that issue. Using the GSOEP we test two hypotheses derived from Borjas and Bratsberg (1996) while allowing for endogeneity of host country specific capital. Our results give strong support for their theory. Additionally a sensitivity analysis shows that the insignificance of education in previous studies is due to the test design conducted and cannot be interpreted as falsification of Borjas’ and Bratsberg’s (1996) theory.return migration, selective return migration

Umsetzung des Hartz IV-Urteils zu weitergehenden Reformen nutzen

In 2005, the assistance for the long-term unemployed in Germany was restructured by the so-called „Hartz IV reform“. An important part of the reform was to replace the former different administrations by a single institution. However, in December 2007, the Federal Constitutional Court decided that the new institution is not consistent with the constitutional law of the Federal Republic of Germany. Thus, a reform of the institution or a change of the constitutional law is necessary. Different reform ideas have been proposed. However, all of them only solve the juristic problem. Not one single reform tries to improve the system. Therefore, the article introduces a new concept of incentive ethics. It shows how the dependency on benefits can be left out by allocating so-called moral goods to the long-term unemployed. A first empirical result supports the concept. Pilot projects should be conducted to get more valid results.

Ausmaß und Ursachen von Niedriglöhnen im ostdeutschen Dienstleistungsgewerbe

In recent years, employment has grown noticeably in Germany. Although this is good news, some people criticize that many jobs are low-paid, i.e. the wage is less than two thirds of the medium wage. An eye-catching example is the service sector in Eastern Germany. However, a systematic analysis of this sector in Eastern Germany is missing until now. The article closes this gap in the literature. Concerning the whole service sector in Eastern Germany, about 25 percent of the employees get a low (gross) wage. This is not much more than the average of all sectors. However, in some branches of the service sector, much more employees get low wages. More than 40% of the employees of retail trade, restaurant business and services near to companies (“unternehmensnahe Dienstleistungen”) are paid low. The probability to get a low wage is significantly higher for women and the so-called minijobbers. Since the tax system adjusts differences, all calculations were also done for net wages. On the one hand, the part of low-paid workers decreases for all branches and all subpopulations. On the other hand, the probability to get a low wage does not differ anymore between minijobbers and full-time employees. Thus, the tax system does not only reduce low-paid employment, it also changes its structure.

Vergleich der Weiterbildungsaktivitäten von Arbeitslosen und Vollzeiterwerbstätigen (Comparing the training activities of unemployed and full-time employed people)

"Many empirical studies for Germany consider either the training activities of the unemployed or those of employees. However, a comprehensive comparison of both groups had not been conducted until now. The paper closes this gap. Using data from the latest time-use survey (Zeitbudgeterhebung) of the Federal Statistical Office, the amount of training undertaken by the two groups is compared. Furthermore, the types of activities that are made use of in particular are described. Heterogeneity due to different relevant socioeconomic characteristics in the two groups is eliminated by applying a matching procedure. The findings demonstrate that only 49 % of unemployed people participate in any kind of training activity off the job. In the case of full-time employment 59 % would take part. Concerning the average expenditure of time per week the difference is reversed, i. e. the expenditure of time is greater during unemployment. However, a large proportion of the training activities undertaken by the unemployed comprises general training, e. g. by reading books or watching television. Furthermore, the result is driven by a different potential of time that can be used for training activities off the job. In relation to this potential of time, the amount of training activity is still smaller during unemployment." (Author's abstract, IAB-Doku) ((en)) Additional Information Kurzfassung (deutsch) Executive summary (English)Weiterbildung, selbstgesteuertes Lernen, Bildungsbeteiligung, Arbeitslose, Erwerbstätige, Vollzeitarbeit, Zeitbudget, Zeitverwendung

Zeitpotential für berufliche Weiterbildung von Arbeitslosen wenig genutzt

In general, unemployed persons spend more time on further training than full-time employees. Using data of the latest time use survey (Zeitbudgeterhebung) of the Federal Statistical Office, this study analyzes whether this higher potential of time is being used or not. Furthermore, it describes which types of activities are made use of in particular. Heterogeneity due to different relevant socioeconomic characteristics in the two groups is eliminated by the appliance of a matching procedure. Findings demonstrate that only around 15 % of the unemployed persons participate in further training activities off the job. In case of the full-time employment just under 40 % of the persons would take part. Relating to the average expenditure of time per week the difference decrease clearly. However, altogether the expenditure of time is not higher during unemployment. A selection of subsamples points out different results, i.e. in some subsamples the expenditure of time for further training is larger during unemployment. However, in the subsample of low skilled persons these results are mainly caused by activities like hearing radio or watching TV. Thus, it is doubtful whether the higher expenditure of time qualifies for the primary labour market.

Ein Konzept der Anreizethik zur Weiterentwicklung der sozialen Grundsicherung nach Hartz IV

"Die Diskussion über eine Reform der sozialen Grundsicherung in Deutschland konzentriert sich oft auf die Veränderung der finanziellen Anreizstruktur und Maßnahmen des 'Workfare'. Das Papier erweitert die Diskussion durch ein neues Konzept der Anreizethik. Mit Hilfe dieses Konzepts werden Schwächen der so genannten 'Hartz IV'-Reform aufgedeckt und weitergehende Reformvorschläge entwickelt." (Autorenreferat)"Reforms of benefits for long-term unemployed in Germany are usually discussed in terms of workfare and financial incentives. This paper broadens the discussion with a concept of incentive ethics. It analyzes how the dependency on benefits can be left out by allocating so-called moral goods to the long-term unemployed. Comparing the new concept with the last reform ('Hartz IV'), the shortcomings of this reform are revealed. Thus, the paper concludes with a new reform proposal." (author's abstract

Homologs of Circadian Clock Proteins Impact the Metabolic Switch Between Light and Dark Growth in the Cyanobacterium Synechocystis sp. PCC 6803

The putative circadian clock system of the facultative heterotrophic cyanobacterial strain Synechocystis sp. PCC 6803 comprises the following three Kai-based systems: a KaiABC-based potential oscillator that is linked to the SasA-RpaA two-component output pathway and two additional KaiBC systems without a cognate KaiA component. Mutants lacking the genes encoding the KaiAB1C1 components or the response regulator RpaA show reduced growth in light/dark cycles and do not show heterotrophic growth in the dark. In the present study, the effect of these mutations on central metabolism was analyzed by targeted and non-targeted metabolite profiling. The strongest metabolic changes were observed in the dark in ΔrpaA and, to a lesser extent, in the ΔkaiAB1C1 mutant. These observations included the overaccumulation of 2-phosphoglycolate, which correlated with the overaccumulation of the RbcL subunit in the mutants, and taken together, these data suggest enhanced RubisCO activity in the dark. The imbalanced carbon metabolism in the ΔrpaA mutant extended to the pyruvate family of amino acids, which showed increased accumulation in the dark. Hence, the deletion of the response regulator rpaA had a more pronounced effect on metabolism than the deletion of the kai genes. The larger impact of the rpaA mutation is in agreement with previous transcriptomic analyses and likely relates to a KaiAB1C1-independent function as a transcription factor. Collectively, our data demonstrate an important role of homologs of clock proteins in Synechocystis for balanced carbon and nitrogen metabolism during light-to-dark transitions