After an introduction which addresses some basic questions, this article is organized around three points: The theoretical framework of the so-called « instrumental approach » which has been a theme in the last

This note estimates the long-run demand for skilled and unskilled labor using panel data for Colombian manufacturing plants. Unobserved heterogeneity and measurement error problems that commonly arise in microdata production estimates are examined. Output measurement errors cause OLS estimators to underestimate the output and wage response of employment demand. Time-difference estimators exagge...

The history of 2-process learning theory is described, and the logical and empirical validity of its major postulates is examined. The assumption of 2 acquisition processes requires the demonstration of an empirical interaction between 2 types of reinforcement contingencies and (a) response classes, (b) reinforcing stimulus classes, or (c) characteristics of the learned behavior itself. The med...

1. AMSA (American Meat Science Association), 1995. Research Guidelines for Cookery Sensory Evaluation, and Instrumental Tenderness Measurement of Fresh Meat. & National Live Stock Board. Chicago IL, (USA). Google Scholar

This study examines the relationships between group faultlines, appraisals (evaluations) of group members, emotional responses, and performance in groups. The study uses a 2 by 2 experimental design, crossing demographic alignment (alignment vs. no alignment) and appraisals (instrumental vs. intrinsic) as between-subjects variables. Data from 5 types of measurement were used to analyze the effe...

Context. Astronomic line mapping with single-pixel heterodyne instruments is usually performed in an on-the-fly (OTF) or a rastermapping mode depending on the capabilities of the telescope and the instrument. The observing efficiency can be increased by combining several source-point integrations with a common reference measurement. This is implemented at many telescopes, but a thorough investi...