Regulation and shadow economy: empirical evidence for 25 OECD-countries

New empirical findings for the impact of regulations on economic activities in the shadow economy are presented here. A comprehensive regulation index covering major fields (e.g. labour and product market regulation and the quality of institutions) has been used to analyze the relationship between the density of regulations and the size of shadow economies. The empirical results from 25 OECD countries for the time period 1995–2005 show that—apart from tax burden and tax moral—main causes for the development of the size of shadow economies are labour and product market regulations, overall regulations and poor quality of official public institutions and administration. These findings can provide additional information on policy measures to tackle the problem of growing shadow economies.     

Quality Marks, Metrics, and Measurement Procedures for Business Process Models

The availability of high-quality business process models is a central prerequisite for a successful process management. Nevertheless, in practice process models exhibit a large number of quality deficits, among them grammatical, content-related, and stylistic defects. In addition, there exist only very few approaches to determine the quality of business process models. In this paper, we present the 3QM-Framework, an analytical approach to systematically determine the quality of business process models. The 3QM-Framework makes three contributions: it provides quality marks, metrics, and measurement procedures to quantify the quality level as elements of a theoretically justified quality model. The applicability of the 3QM-Framework has been empirically evaluated in case studies. The results of a survey that was conducted among experts moreover attest its practical relevance.     

Age,employability and the role of learning activities and their motivational antecedents: a conceptual model

In today's time of demographic change and rapid innovation, age and employability as well as the role of learning and development are high on the agenda of human resource managers and chief learning officers. However, existing research has failed to integrate these concepts in a clear model and offers little explanation of how the concepts may be linked exactly. In this conceptual paper we show how chronological age, despite its poor characteristics as a predictor, might still affect employability indirectly. Specifically, we propose that employees' motivation – in terms of future time perspective and goal orientation – and formal and informal learning activities need to be considered. Since an individual's chronological age cannot be changed, it is important to recognize these mediating variables, which may be targeted more easily by human resource development or age management initiatives.     

Vor der Bundestagswahl: Argumente für Mindestlöhne überzeugen nicht

For the first time ever, all political parties represented in the German Bundestag are proposing some form of minimum wage regulation in their federal campaigns. After sketching an overview of the vast empirical literature on the employment effects of minimum wages, which has yet to come to a consensus, the paper concentrates on the most common theoretical arguments for the view that minimum wages need not reduce the employment levels of affected workers. The authors find that those arguments are either conceptually inconsistent or assume market characteristics that can hardly describe the reality of low-wage labour markets. In the end, minimum wages are a blunt instrument to reduce poverty among workers — its primary objective — because it benefits many that are not poor and does not address the most important determinant of poverty in Germany, namely unemployment.     

Progressive Lending as an Enforcement Mechanism in Microfinance Programs

Microfinance programs are often characterized by progressive lending. A typical borrower receives at first very small amounts, which increase with good repayment conduct. The author rationalizes this feature of microfinance. It is shown that there is a strong tendency to split up projects into subprojects, and that it might be necessary to perform less productive projects first in order to keep pressure on the borrower to repay.     

Same place,same knowledge – same people? The geography of non-patent citations in Dutch polymer patents

It has long been argued that geographic co-location supports knowledge spillovers. More recently, this argument has been challenged by showing that knowledge spillovers mainly flow through social networks, which may or may not be localized at various geographic scales. We further scrutinize the conjecture of geographically bounded knowledge spillovers by focusing on knowledge flows between academia and industry. Looking into citations to non-patent literature (NPL) in 2385 Dutch polymer patents, we find that citation lags are shorter on average if Dutch rather than foreign NPLs are cited. However, when excluding individual and organizational self-citations, geographically proximate NPLs no longer diffuse faster than foreign NPLs. This suggests that knowledge is not ‘in the air’ but transferred by mobile individuals and/or direct university–industry collaboration. Our findings moreover suggest an important role of international conferences in the diffusion of recent scientific knowledge.     

主要经济区域中的货币错位和贸易不平衡

本文论及在世界主要经济区城货币错位和贸易不平衡、货币错位产生的原因及其解决的方法，介绍了现行国际货币体系及其缺陷和改革建议。文中主要涉及到美国、欧盟、日本和中国的经济发展水平和相应的货币政策。     

Multi-asset portfolio optimization and out-of-sample performance: an evaluation of Black–Litterman,mean-variance,and naïve diversification approaches

The Black–Litterman model aims to enhance asset allocation decisions by overcoming the problems of mean-variance portfolio optimization. We propose a sample-based version of the Black–Litterman model and implement it on a multi-asset portfolio consisting of global stocks, bonds, and commodity indices, covering the period from January 1993 to December 2011. We test its out-of-sample performance relative to other asset allocation models and find that Black–Litterman optimized portfolios significantly outperform naïve-diversified portfolios (1/N rule and strategic weights), and consistently perform better than mean-variance, Bayes–Stein, and minimum-variance strategies in terms of out-of-sample Sharpe ratios, even after controlling for different levels of risk aversion, investment constraints, and transaction costs. The BL model generates portfolios with lower risk, less extreme asset allocations, and higher diversification across asset classes. Sensitivity analyses indicate that these advantages are due to more stable mixed return estimates that incorporate the reliability of return predictions, smaller estimation errors, and lower turnover.