Raising "lab rats"

Experimental subjects usually self-select to the laboratory and this may introduce a bias to the derived conclusions. We analyze data stored by a subject-pool management software at an experimental laboratory and speculate about the eect of individual decisions on returning. In particular, we test whether experience and earnings in previous sessions together with demographic variables explain the decision to return to the laboratory. We nd that males and (in monetary terms) well-performing subjects are more likely to participate again in experiments.demographic characteristics, experiments, subject pool

Global Competition, Institutions, And The Diffusion Of Organizational Practices: The International Spread Of Iso 9000 Quality Certificates

We use panel data on ISO 9000 quality certification in 85 countries between 1993 and 1998 to better understand, the cross-national diffusion of an organizational practice. Following neoinstitutional theory, we focus on the coercive, normative, and mimetic effects that result from the exposure of firms in a given country to a powerful source of critical resources, a common pool of relevant technical knowledge, and the experiences of firms located in other countries. We use social network theory to develop a systematic conceptual understanding of how firms located in different countries influence each other's rates of adoption as a result of cohesive and equivalent network relationships. Regression results provide support for our predictions that states and foreign multinationals are the key actors responsible for coercive isomorphism, cohesive trade relationships between countries generate coercive and normative effects, and role-equivalent trade relationships result in learning-based and competitive imitation.Business Administratio

Moduli Spaces and Formal Operads

Let overline{M}_{g,n} be the moduli space of stable algebraic curves of genus g with n marked points. With the operations which relate the different moduli spaces identifying marked points, the family (overline{M}_{g,n})_{g,n} is a modular operad of projective smooth Deligne-Mumford stacks, overline{M}. In this paper we prove that the modular operad of singular chains C_*(overline{M};Q) is formal; so it is weakly equivalent to the modular operad of its homology H_*(overline{M};Q). As a consequence, the "up to homotopy" algebras of these two operads are the same. To obtain this result we prove a formality theorem for operads analogous to Deligne-Griffiths-Morgan-Sullivan formality theorem, the existence of minimal models of modular operads, and a characterization of formality for operads which shows that formality is independent of the ground field.Comment: 36 pages (v3: some typographical corrections

A Cartan-Eilenberg approach to Homotopical Algebra

In this paper we propose an approach to homotopical algebra where the basic ingredient is a category with two classes of distinguished morphisms: strong and weak equivalences. These data determine the cofibrant objects by an extension property analogous to the classical lifting property of projective modules. We define a Cartan-Eilenberg category as a category with strong and weak equivalences such that there is an equivalence between its localization with respect to weak equivalences and the localised category of cofibrant objets with respect to strong equivalences. This equivalence allows us to extend the classical theory of derived additive functors to this non additive setting. The main examples include Quillen model categories and functor categories with a triple, in the last case we find examples in which the class of strong equivalences is not determined by a homotopy relation. Among other applications, we prove the existence of filtered minimal models for \emph{cdg} algebras over a zero-characteristic field and we formulate an acyclic models theorem for non additive functors

Modernism Without Modernity: The Rise of Modernist Architecture in Mexico, Brazil, and Argentina, 1890-1940

: Why did machine-age modernist architecture diffuse to Latin America so quickly after its rise in Continental Europe during the 1910s and 1920s? Why was it a more successful movement in relatively backward Brazil and Mexico than in more affluent and industrialized Argentina? After reviewing the historical development of architectural modernism in these three countries, several explanations are tested against the comparative evidence. Standards of living, industrialization, sociopolitical upheaval, and the absence of working-class consumerism are found to be limited as explanations. As in Europe, Modernism diffused to Latin America thanks to state patronage and the professionalization of architects following an engineering model

International Coercion, Emulation and Policy Diffusion: Market-Oriented Infrastructure Reforms, 1977-1999

Why do some countries adopt market-oriented reforms such as deregulation, privatization and liberalization of competition in their infrastructure industries while others do not? Why did the pace of adoption accelerate in the 1990s? Building on neo-institutional theory in sociology, we argue that the domestic adoption of market-oriented reforms is strongly influenced by international pressures of coercion and emulation. We find robust support for these arguments with an event-history analysis of the determinants of reform in the telecommunications and electricity sectors of as many as 205 countries and territories between 1977 and 1999. Our results also suggest that the coercive effect of multilateral lending from the IMF, the World Bank or Regional Development Banks is increasing over time, a finding that is consistent with anecdotal evidence that multilateral organizations have broadened the scope of the “conditionality” terms specifying market-oriented reforms imposed on borrowing countries. We discuss the possibility that, by pressuring countries into policy reform, cross-national coercion and emulation may not produce ideal outcomes.Privatization, deregulation, liberalization, infrastructure, International Monetary Fund (IMF), World Bank, Multileral Institutions, Development, Reform, Globalization, Adoption, International

Scintillation observations at Ancon and Jicamarca Observatories

Satellite scintillation and diffraction pattern scale size distribution from ionospheric irregularitie

NGC 6309, a Planetary Nebula that Shifted from Round to Multipolar

We present new narrow-band Ha, [N II], and [O III] high-resolution images of the quadrupolar planetary nebula (PN) NGC 6309 that show in great detail its bipolar lobes and reveal new morphological features. New high- and low-dispersion long-slit spectra have been obtained to help in the investigation of the new nebular components. The images and spectra unveil two diffuse blobs, one of them located at 55 arcsec from the central star along the NE direction (PA= +71) and the other at 78 arcsec in the SW direction (PA= -151). Therefore, these structures do not share the symmetry axes of the inner bipolar outflows. Their radial velocities relative to the system are quite low: +3 and -4 km/s, respectively. Spectroscopic data confirm a high [O III] to Ha ratio, indicating that the blobs are being excited by the UV flux from the central star. Our images convincingly show a spherical halo 60 arcsec in diameter encircling the quadrupolar nebula. The expansion velocity of this shell is low, 66 km/s. The software SHAPE has been used to construct a morpho-kinematic model for the ring and the bipolar flows that implies an age of 4,000 yrs, the expansion of the halo sets a lower limit for its age 46,000 yrs, and the very low expansion of the blobs suggests they are part of a large structure corresponding to a mass ejection that took place 150,000 yrs ago. In NGC 6309 we have direct evidence of a change in the geometry of mass-loss, from spherical in the halo to axially-symmetric in the two pairs of bipolar lobes.Comment: 8 pages, 7 figures, Accepted for publication in MNRA