A Proof of Determinacy in the New-Keynesian Sticky Wages and Prices Model

The paper is concerned with determinacy in a version of the New-Keynesian model that integrates imperfect competition and nominal price and wage setting on goods and labour markets. The model is reformulated with an explicit period of arbitrary length and shown to remain well-defined as the period shrinks to zero. The 4×4 constituent matrix of the model?s continuous-time counterpart is mathematically tractable and its determinacy results carry over to the period model at least if the period is sufficiently short. This being understood, it is proved that determinacy is (essentially) ensured if an extended Taylor principle requirement is met. --Determinacy,New-Keynesian wage and price Phillips curves,variable period length,continuous-time limit,Taylor principle

On the Determinacy of New Keynesian Models with Staggered Wage and Price Setting

This paper shows that an analytical determinacy analysis of the baseline New Keynesian model with both staggered wages and prices developed by Erceg, Henderson and Levin (2000) is possible despite the high dimensional nature of this model. It is possible if the formulation of the model is translated from discrete to continuous time. Our findings corroborates in an analytical manner Galí's (2008) numerical findings regarding the determinacy frontier and the Taylor principle for this model type, where a generalized Taylor rule that employs a weighted combination of wage and price inflation is used as a measure for the inflation gap.Period models, continuous time, (in)determinacy.

Designing Embodied Interactive Software Agents for E-Learning: Principles, Components, and Roles

Embodied interactive software agents are complex autonomous, adaptive, and social software systems with a digital embodiment that enables them to act on and react to other entities (users, objects, and other agents) in their environment through bodily actions, which include the use of verbal and non-verbal communicative behaviors in face-to-face interactions with the user. These agents have been developed for various roles in different application domains, in which they perform tasks that have been assigned to them by their developers or delegated to them by their users or by other agents. In computer-assisted learning, embodied interactive pedagogical software agents have the general task to promote human learning by working with students (and other agents) in computer-based learning environments, among them e-learning platforms based on Internet technologies, such as the Virtual Linguistics Campus (www.linguistics-online.com). In these environments, pedagogical agents provide contextualized, qualified, personalized, and timely assistance, cooperation, instruction, motivation, and services for both individual learners and groups of learners. This thesis develops a comprehensive, multidisciplinary, and user-oriented view of the design of embodied interactive pedagogical software agents, which integrates theoretical and practical insights from various academic and other fields. The research intends to contribute to the scientific understanding of issues, methods, theories, and technologies that are involved in the design, implementation, and evaluation of embodied interactive software agents for different roles in e-learning and other areas. For developers, the thesis provides sixteen basic principles (Added Value, Perceptible Qualities, Balanced Design, Coherence, Consistency, Completeness, Comprehensibility, Individuality, Variability, Communicative Ability, Modularity, Teamwork, Participatory Design, Role Awareness, Cultural Awareness, and Relationship Building) plus a large number of specific guidelines for the design of embodied interactive software agents and their components. Furthermore, it offers critical reviews of theories, concepts, approaches, and technologies from different areas and disciplines that are relevant to agent design. Finally, it discusses three pedagogical agent roles (virtual native speaker, coach, and peer) in the scenario of the linguistic fieldwork classes on the Virtual Linguistics Campus and presents detailed considerations for the design of an agent for one of these roles (the virtual native speaker)

Labor Productivity and the Law of Decreasing Labor Content

This paper analyzes labor productivity and the law of decreasing labor content (LDLC) originally formulated by Farjoun and Machover (1983). First, it is shown that the standard measures of labor productivity may be rather misleading, owing to their emphasis on monetary aggregates. Instead, the conventional classical-Marxian labor values provide the theoretically and empirically sound measures of labor productivity. The notion of labor content and the LDLC are therefore central in order to understand the dynamics of capitalist economies. Second, some rigorous theoretical relations between different forms of profit-driven technical change and productivity are derived in a general input-output framework with fixed capital, which provide deterministic foundations to the LDLC. Third, the main theoretical propositions are analyzed empirically based on a new dataset of the German economy. JEL Categories: B51, D57, O33, C67labor productivity, law of falling labor content, technical change, labor values, Input-Output analysis.

Vendor-Managed Inventory for High Value Parts : Results from a survey among leading international manufacturing firms

Vendor-managed inventory (VMI) is common practice in mass-market environments and for high-volume, low-value items. But increasingly, also firms that produce low volumes of high value products are looking into VMI to reduce supply chain inventory and to be able to concentrate on their customer-side processes. This study shows how some leading international manufacturing firms have implemented vendor-managed inventory with their suppliers. Some of these firms have been practicing VMI for high value parts for more than ten years and continue to extend their schemes to include more items and suppliers. The study proposes a new structural framework specifying alternative solutions with respect to information, commercial and physical processes. Based on the survey findings, the author gives recommendations to firms looking at implementing VMI. Printed version available by Universitätsverlag der TU Berlin, ISBN 978-3-7983-2211-

Interacting Two-Country Business Fluctuations

In this paper we investigate the closed-economy Keynes-Wicksell-Goodwin model of Chiarella and Flaschel (2000) for the case of two interacting open economies. We introduce these coupled two-country KWG dynamics on the extensive form level by means of a subdivision into nine modules describing the behavioral equations, the laws of motion and the identities or budget equations of the model. We then derive their intensive form representation and the 10 laws of motion of the model on the basis of certain simplifying assumptions. Thereafter we present the uniquely determined steady state solution of the dynamics and discuss in a mathematically informal way its stability properties, concerning asymptotic stability and loss of stability by way of super- or subcritical Hopf-bifurcations. In a final section we explore numerically a variety of situations of interacting real and financial cycles, where the steady state is locally repelling, but where the overall dynamics are bounded in an economically meaningful domain by means of a kinked money wage Phillips curve, exhibiting downward rigidity of the money-wage, coupled with upward flexibility of the usual type.Interacting KWG economies, stability, persistent cycles, coupled oscillators.

Analytical Quartic Centrifugal Distortion Constants By Fourth-order Rayleigh SchrÖdinger Perturbation Theory

Recent advances in microwave spectroscopy, allowing for the measurement and fitting of thousands of spectral lines for a given chemical system, have prompted a need for high accuracy predictions of spectroscopic constants. The quartic Centrifugal Distortion (CD) constants are derived at fourth-order in Rayleigh-Schr\"{o}dinger Vibrational Perturbation Theory (VPT4). Analytical expressions are presented. The constants are implemented in the CFOUR software package in both an explicit sum-over-states form and the analytical (i.e., algebraic) form. The expression for VPT4 quartic CD can be broken into ten distinct contributions, involving products of force constants, Coriolis constants, and coefficients in the expansion of the inverse moment of inertia tensor. It is considerably more complicated than the VPT2 vibration-rotation interaction constants and the VPT4 sextic CD constants. The quartic CD constants first appear at VPT2. The VPT4 level of approximation introduces corrections that are linear in the vibrational quantum numbers. Approximately linear relationships have been identified in analyses of microwave spectra, which allow for direct comparison with the computed CD constants. The VPT4 quartic CD constants require a partial quartic force field, containing all force constants except those for which all indices are different (i.e., $\phi$$_{ijkl}$). As this truncation of quartic force field is usually computed for VPT2 vibrational frequencies, it will be possible to obtain the CD constants alongside routine VPT2 frequencies with negligible added cost

Living in Two Worlds: Multi-Locational Household Arrangements among Migrant Workers in China

In the past, the concept of multi-locality has hardly been applied to the study of livelihood strategies of migrant workers in China. The authors of this article present the findings of a research project in five selected rural-urban migration corridors in different parts of China. On the basis of qualitative interviews at both ends of the multi-locational households’ activity spaces, they were able to establish economic reciprocity, strategies for caring and the transfer of knowledge, values and beliefs at the household level. The multi-locational households – defined as units of joint planning – were found to be firmly embedded in informal social networks

A Novel Energy and Momentum Consistent Mixed Formulation for Coupled Nonlinear Electro‐Thermo‐Elastodynamics

In the present contribution, a novel mixed formulation aimed at the energy-momentum consistent simulation of coupled nonlinear electro-thermo-elastodynamic systems, in particular dielectric elastomer actuators, is proposed. It is essentially based on a mixed framework for elastodynamics in the case of polyconvex stored energy functions. In accordance with this framework, the properties of the rediscovered tensor cross product are exploited in a first step to derive a mixed formulation via a Hu-Washizu type extension of the stored energy function. Afterwards, the corresponding strong form is derived and supplemented with the (initial) boundary value problems of thermodynamics and electrostatics. By additionally choosing an appropriate polyconvexity-inspired energy density function, this procedure leads to a fully coupled electro-thermo-elastodynamic formulation that benefits from the properties of the underlying mixed framework. Furthermore, an energy-momentum consistent time integration scheme is proposed for the novel framework, where discrete derivatives in the sense of Gonzalez are employed. The formulation is second-order accurate and stable even for large time step sizes. Eventually, the performance of the novel formulation is illustrated in a numerical example