Approximate maximum likelihood estimation for stochastic differential equations with random effects in the drift and the diffusion

Consider N independent stochastic processes \((X_i(t), t\in [0,T])\), \(i=1,\ldots , N\), defined by a stochastic differential equation with random effects where the drift term depends linearly on a random vector \(\Phi _i\) and the diffusion coefficient depends on another linear random effect \(\Psi _i\). For these effects, we consider a joint parametric distribution. We propose and study two approximate likelihoods for estimating the parameters of this joint distribution based on discrete observations of the processes on a fixed time interval. Consistent and \(\sqrt{N}\)-asymptotically Gaussian estimators are obtained when both the number of individuals and the number of observations per individual tend to infinity. The estimation methods are investigated on simulated data and show good performances.     

Media-Based Sentiment Indices as an Alternative Measure of Consumer Confidence

In this paper, we consider the feasibility of constructing online sentiment indices, using large amounts of media data, as an alternative to the conventional survey method used to create the consumer confidence index in South Africa. A clustering framework is adopted to provide an indication of possible candidate sentiment indices constructed from a combination of different text sources and dictionaries that best mimic the traditional survey-based consumer confidence index from the South African Bureau for Economic Research (BER). The results conclude that it is possible to create an index using sentiment analysis using online editorial data that does resemble the BER’s consumer confidence index. The different media-based sentiment indices (MSI) show a significant level of correlation and co-movement with the BER’s CCI. Impulse responses and cross-correlation functions indicate that the MSI could potentially lead the survey-based method up to two quarters. Furthermore, Granger-causality tests show that the media-based indices are good predictors of future consumer confidence index values. The results provide motivation for further study on the use of sentiment-based techniques and online media data sources to track consumer confidence within an emerging market such as South Africa.     

When innovation in education works: stimulating teachers' innovative work behaviour

The twenty‐first century labour market requires employees that proactively shape innovations and solve complex problems. Professionals in the education sector are expected to perform innovative behaviour that not only entails the generation, but also the realization and sustainable implementation of new ideas. In a sample of 458 employees in Dutch secondary and higher vocational education (abbreviated in Dutch to MBO and HBO, respectively), this study investigated the relation between environmental factors (namely task variety, management support and exposure to innovation) and Innovative Work Behaviour (IWB) across the different phases of the innovation process, including a sustainability phase. Results of hierarchical regression analyses showed that management support and exposure to innovations served as a predictor for all phases of IWB. Teachers with supportive managers and a high degree of exposure to innovations showed higher scores on innovative behaviour across all phases. Linear regressions revealed a significant relationship between task variety and IWB. In the hierarchical model, only management suport and exposure to innovations showed significant relations. Background characteristics, such as gender, age, tenure, number of working hours and type of education, for which we controlled during the analyses, played a role in how much IWB is displayed. It can be concluded that a work environment, in which employees are exposed to innovation and are supported is crucial. Additionally, in view of the role background characteristics play, it is recommended to select teachers with specific profiles for the different phases of the innovation process.     

Old wine in new bottles? Revisiting employee participation in Industry 4.0

This paper aims to critically examine employee participation in Industry 4.0, with a systematic literature review. A total of 58 studies were reviewed, resulting in a categorisation of the literature into three perspectives. The ‘techno‐optimist’ and the ‘socio‐technical’ perspective dominate in the reviewed papers. They both confirm a trend that frames employee participation in a unitarist tradition, which emphasises synergies between managerial efficiency and (mostly individual) participation, leading to high innovation potential. The third perspective is rooted in critical studies. Authors writing on the latter subject predict more standardisation and centralisation, and the continued demise of collective and representative forms of participation. To better understand the role of employees in Industry 4.0, we suggest confronting the current discourse with robust empirical research. On that basis, we reject both technological and social determinism, and we acknowledge the structural ambiguities and multidimensionality of employee participation in technological transformations.     

Basic Income in the Finnish Context

The goal of the Finnish experiment that started this year is to try to get some evidence on how a new social policy instrument mimicking a basic income would work and what kind of behavioural consequences it would have. At this point, there are many strong arguments being made both in favour of and opposed to basic income. Unfortunately, there are not enough facts yet. The Finnish experiment hopes to change that.     

Autonomous Driving — a Challenge for the Automotive Industry

The automotive industry is one of the most important industries in Europe. This industry is responsible for 14% of total production and capital investment in the European manufacturing sector, and in Germany the share amounts to 22%. Structural change within this crucial sector is of relevance for the whole economy. Along with alternative propulsion systems such as electromobility, (semi-)autonomous vehicles are one of the big trends in the automotive industry. For established providers, the possibility of disruptive change poses a threat to existing markets, while a gradual introduction of new technologies also increases competition. Nevertheless, with their strong market position in the premium segment and especially their relevant research activities, European and especially German automotive manufacturers are well placed to successfully master the coming challenges in the automotive market.     

ANFA — National Money Creation as an Existential Threat to the Currency Union?

The recent publication of the previously secret Agreement on Net Financial Assets (ANFA) directed the public’s attention to the possibility that national central banks could create money through purchases of securities on their own account. This paper provides an overview of the legal foundations for ANFA and shows the varying extent to which the member countries use these regulations. What are the interests, risks and consequences for the countries in crisis and the currency union as a whole? Is the ECB properly monitoring ANFA purchases? Could money creation via ANFA act as an explosive device for the currency union?     

Assessing Industrial Buyer Preferences: Using the Swait-Louviere Test to Test the Key Informant Assumption

When using professional buyers to study an organizations buying behavior an important consideration is whether their preferences reflect those of the organization. Since this is a key informant problem, the present article focuses on the issue of the degree to which key informants can be used to provide insights into their own organizations preferences. We conduct a direct test of the key informant assumption using the Swait-Louviere test. In this test preferences from a choice experiment using actual buyers, and from market decisions made by the organization, are estimated separately, then jointly in multinomial logit models. We found that buyers experimental preferences were similar to estimates obtained from the market decisions. Buyers preferences were closer to the intuitive preferences of the organizations top executives than the estimates based on past market decisions, although a model based on the combined data outperformed either. We discuss the implications of these results for industrial buying research.This revised version was published online in May 2005 with a corrected cover date.     

Contracting Under Endogenous Risk

Agents make decisions by trading off cost, return and risk. The literature, however, does not consider the impact of risk on action choice. We show that this tradeoff has important implications for the firm. First, the firm may provide no insurance in the salary. Since the agents action choice will determine her risk, the salary cannot compensate her for it. Second, the firm may not be able to design an incentive scheme to implement particularly risky actions. Finally, the firm may not be able to design a scheme in which the agent splits her effort across multiple tasks. This is particularly problematic for tasks that are technological substitutes.     

Schlechter Wein in alten Schläuchen—Eine Replik auf Helmedag

In der Januarausgabe des WIRTSCHAFTSDIENST ver?ffentlichten wir einen Aufsatz von Professor Fritz Helmedag über die „Abh?ngigkeit der Besch?ftigung von Steuern, Budgetdefiziten und L?hnen“. Hierzu eine Replik von Professor Bernd Lucke und eine Erwiderung von Professor Fritz Helmedag.