Performance Appraisals and the Impact of Forced Distribution: An Experimental Investigation

A real effort experiment is investigated in which supervisors have to rate the performance of individual workers who in turn receive a bonus payment based on these ratings. We compare a baseline treatment in which supervisors were not restricted in their rating behavior to a forced distribution system in which they had to assign differentiated grades. We find that productivity was significantly higher under a forced distribution by about 8%. But also in the absence of forced distribution, deliberate differentiation positively affected output in subsequent work periods.performance measurement, forced distribution, motivation, experiment

Incentives and Cooperation in Firms: Field Evidence

We empirically investigate the impact of incentive scheme structure on the degree of cooperation in firms using a unique and representative data set. Combining employee survey data with detailed firm level information on the relative importance of individual, team, and company performance for compensation, we find a significant positive relation between the intensity of team incentives and several survey measures of cooperation. Moreover, higher powered team incentives are associated with lower degrees of absenteeism while this is not the case for individual incentives.incentives, cooperation, teams, helping effort

Managerial Incentives and Favoritism in Promotion Decisions: Theory and Field Evidence

This paper investigates the effects of managerial incentives on favoritism in promotion decisions. First, we theoretically show that favoritism leads to a lower quality of promotion decisions and in turn lower efforts. But the effect can be mitigated by pay-for-performance incentives for managers who decide upon promotion. Second, we analyze matched employer-employee survey data with detailed firm level information on managerial incentive schemes and find that perceived promotion quality is indeed substantially higher when managers receive performance-related pay or participate in gain sharing plans.incentives, favoritism, nepotism, tournaments

Interplay of electronic correlations and lattice instabilities in BaVS3

The quasi-one-dimensional metallic system BaVS3 with a metal-insulator transition at T_MI=70 K shows large changes of the optical phonon spectrum, a central peak, and an electronic Raman scattering continuum that evolve in a three-step process. Motivated by the observation of a strongly fluctuating precursor state at high temperatures and orbital ordering and a charge gap at low temperatures we suggest a concerted action of the orbital, electronic, and lattice subsystems dominated by electronic correlations.Comment: 4 pages, 4 figure

Development of an integrated solar-fossil powered steam generation system for industrial applications

Das Poster gibt eine kurze Einführung in das Projekt SolSteam, in dem die Integration solaren Prozessdampfes in einen konventionellen Dampferzeuger untersucht wird

Empirical comparison between factor analysis and item response models

Many multidimensional item response theory (IRT) models have been proposed. A comparison is made between the so-called full information models and the models that use only pairwise information. Three multidimensional models described are: (1) the compensatory model of R. D. Bock and M. Aitken (1981) using the computer program TESTFACT; (2) a model based on R. P. McDonald's (1985) harmonic analysis using the program NOHARM; and (3) the computer program MAXLOG of R. L. McKinley and M. D. Reckase (1983). Five factor analysis procedures for dichotomous items are discussed. A simulation study was conducted to compare the various methods. The item parameters of four different sets of items were used with numbers of subjects set at 250, 500, and 1,000. Ten replications were generated for each set of item parameters and each sample size. All models were compared with respect to estimates of IRT and factor analysis parameters using six criteria in terms of mean squared differences between the known and estimated item parameters. The most striking result of the simulation study was that common factor analysis programs outperformed the more complex programs TESTFACT, MAXLOG, and NOHARM. It was apparent that a common factor analysis in the matrix of tetrachoric correlations yielded the best estimates. A procedure based on the mean squared residuals of the correlation matrix was also presented for assessing the dimensionality of the model. Nine tables present the data from the simulation study

Benchmarking of Flatness-based Control of the Heat Equation

Flatness-based control design is a well established method to generate open-loop control signals. Several articles discuss the application of flatness-based control design of (reaction-) diffusion problems for various scenarios. Beside the pure analytical derivation also the numerical computation of the input signal is crucial to yield a reliable trajectory planning. Therefore, we derive the input signal step-by-step and describe the influence of system and controller parameters on the computation of the input signal. In particular, we benchmark the control design of the one-dimensional heat equation with Neumann-type boundary actuation for pure aluminum and steel 38Si7, and discuss the applicability of the found input signals for realistic scenarios.Comment: 9 Pages, 13 Figure

Strong coupling between single photons in semiconductor microcavities

We discuss the observability of strong coupling between single photons in semiconductor microcavities coupled by a chi(2) nonlinearity. We present two schemes and analyze the feasibility of their practical implementation in three systems: photonic crystal defects, micropillars and microdisks, fabricated out of GaAs. We show that if a weak coherent state is used to enhance the chi(2) interaction, the strong coupling regime between two modes at different frequencies occupied by a single photon is within reach of current technology. The unstimulated strong coupling of a single photon and a photon pair is very challenging and will require an improvement in mirocavity quality factors of 2-4 orders of magnitude to be observable.Comment: 4 page

Determination of the effective detector area of an energy-dispersive X-ray spectrometer at the scanning electron microscope using experimental and theoretical X-ray emission yields

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.A method is proposed to determine the effective detector area for energy-dispersive X-ray spectrometers (EDS). Nowadays, detectors are available for a wide range of nominal areas ranging from 10 up to 150 mm2. However, it remains in most cases unknown whether this nominal area coincides with the “net active sensor area” that should be given according to the related standard ISO 15632, or with any other area of the detector device. Moreover, the specific geometry of EDS installation may further reduce a given detector area. The proposed method can be applied to most scanning electron microscope/EDS configurations. The basic idea consists in a comparison of the measured count rate with the count rate resulting from known X-ray yields of copper, titanium, or silicon. The method was successfully tested on three detectors with known effective area and applied further to seven spectrometers from different manufacturers. In most cases the method gave an effective area smaller than the area given in the detector description