Sociality and external validity in experimental economics

It is sometimes argued that experimental economists do not have to worry about external validity so long as the design sticks closely to a theoretical model. This position mistakes the model for the theory. As a result, applied economics designs often study phenomena distinct from their stated objects of inquiry. Because the implemented models are abstract, they may provide improbable analogues to their stated subject matter. This problem is exacerbated by the relational character of the social world, which also sets epistemic limits for the social science laboratory more generally.

Effect of disease-selective predation on prey infected by contact and external sources

We propose and analyze a simple mathematical model for susceptible prey (S)–infected prey (I)–predator (P) interaction, where the susceptible prey population (S) is infected directly from external sources as well as through contact with infected class (I) and the predator completely avoids consuming the infected prey. The model is analyzed to obtain different thresholds of the key parameters under which the system exhibits stability around the biologically feasible equilibria. Through numerical simulations we display the effects of external infection and the infection through contact on the system dynamics in the absence as well as in the presence of the predator. We compare the system dynamics when infection occurs only through contact, with that when it occurs through contact and external sources. Our analysis demonstrates that under a disease-selective predation, stability and oscillations of the system is determined by two key parameters: the external infection rate and the force of infection through contact. Due to the introduction of external infection, the predator and the prey population show limit-cycle oscillations over a range parametric values. We suggest that while predicting the dynamics of such an eco-epidemiological system, the modes of infection and the infection rates might be carefully investigated.

Internal equity financing and the performance of multinational subsidiaries in emerging economies

We examine the internal equity financing of the multinational subsidiary which retains and reinvests its own earnings. Internal equity financing is a type of firm-specific advantage (FSA) along with other traditional FSAs in innovation, research and development, brands and management skills. It also reflects subsidiary-level financial management decision-making. Here we test the contributions of internal equity financing and subsidiary-level financial management decision-making to subsidiary performance, using original survey data from British multinational subsidiaries in six emerging countries in the South East Asia region. Our first finding is that internal equity financing acts as an FSA to improve subsidiary performance. Our second finding is that over 90% of financing sources (including capital investment by the parent firms) in the British subsidiaries come from internal funding. Our third finding is that subsidiary-level financial management decision-making has a statistically significant positive impact on subsidiary performance. Our findings advance the theoretical, empirical and managerial analysis of subsidiary performance in emerging economies.

Revisiting trends in wetness and dryness in the presence of internal climate variability and water limitations over land

A theoretically expected consequence of the intensification of the hydrological cycle under global warming is that on average, wet regions get wetter and dry regions get drier (WWDD). Recent studies, however, have found significant discrepancies between the expected pattern of change and observed changes over land. We assess the WWDD theory in four climate models. We find that the reported discrepancy can be traced to two main issues: (1) unforced internal climate variability strongly affects local wetness and dryness trends and can obscure underlying agreement with WWDD, and (2) dry land regions are not constrained to become drier by enhanced moisture divergence since evaporation cannot exceed precipitation over multiannual time scales. Over land, where the available water does not limit evaporation, a “wet gets wetter” signal predominates. On seasonal time scales, where evaporation can exceed precipitation, trends in wet season becoming wetter and dry season becoming drier are also found.

Objective Assessment of Internal Nasal Dimensions and Speech Resonance in Individuals With Repaired Unilateral Cleft Lip and Palate After Rhinoseptoplasty

The objective of the current study was to analyze the effects of rhinoseptoplasty on internal nasal dimensions and speech resonance of individuals with unilateral cleft lip and palate, estimated by acoustic rhinometry and nasometry, respectively. Twenty-one individuals (aged 15-46 years) with previously repaired unilateral cleft lip and palate were analyzed before (PRE), and 6 to 9 (POST1) and 12 to 18 months (POST2) after surgery. Acoustic rhinometry was used to measure the cross-sectional areas (CSAs) of segments corresponding to the nasal valve (CSA1), anterior portion (CSA2), and posterior portion (CSA3) of the lower turbinate, and the volumes at the nasal valve (V1) and turbinate (V2) regions at cleft and noncleft sides, before and after nasal decongestion with a topical vasoconstrictor. Nasometry was used to evaluate speech nasalance during the reading of a set of sentences containing nasal sounds and other devoid of nasal sounds. At the cleft side, before nasal decongestion, there was a significant increase (P < 0.05) in mean CSA1 and V1 values at POST1 and POST2 compared with PRE. After decongestion, increased values were also observed for CSA2 and V2 at POST2. No significant changes were observed at the noncleft side. Mean nasalance values at PRE, POST1, an POST2 were not different from each other in both oral and nasal sentences. The measurement of CSAs and volumes by acoustic rhinometry revealed that rhinoseptoplasty provided, in most cases analyzed, a significant increase in nasal patency, without concomitant changes in speech resonance, as estimated by nasalance assessment.

Excited Electronic States, Transition Probabilities, and Radiative Lifetimes of CAs: A Theoretical Contribution and Challenge to Experimentalists

High-level CASSCF/MRCI calculations with a quintuple-zeta quality basis set are reported by characterizing for the first time a manifold of electronic states of the CAs radical yet to be investigated experimentally. Along with the potential energy curves and the associated spectroscopic constants, the dipole moment functions for selected electronic states as well as the transition dipole moment functions for the most relevant electronic transitions are also presented. Estimates of radiative transition probabilities and lifetimes complement this investigation, which also assesses the effect of spin-orbit interaction on the A (2)Pi state. Whenever pertinent, comparisons of similarities and differences with the isovalent CN and CP radicals are made.

The effects of Ikea and external shopping centers on regional trade and retail growth : A comparative analysis of Ikea’s establishment in Kalmar and Karlstad

This paper examines the effects of Ikea store establishment in Kalmar and Karlstad on the trade and retail inside the two cities, and as well on the trade and retail in the close neighboring municipalities and in further peripheral municipalities in both regions. After the establishment of Ikea store, Kalmar and Karlstad have experienced significant growth in trade and retail. The question, however, is how big this growth is in both cities? And how different locations on different distances from Ikea have been affected? What impact there was on different segments of the retail? How different business branches have been affected? How large the catchment area for the emerging new large-scale retail locations is? These questions, in addition to few others, are investigated in this paper. The thesis starts with an introduction chapter containing a background of the topic, problem description, the investigated questions, the purpose, and the outline of the paper. The next chapter includes the frame of reference which consists of literature review and theoretical framework about the external shopping centers and their impact on retail and regional trade development. It includes also information gathered from previous studies technical reports and other available sources about the subject. The third chapter includes description for the methods used to collect the primary and secondary data needed for the purpose of this study. Then the empirical framework which demonstrates the results of the conducted research followed by analysis and concluded in discussion and conclusion. Mixed methods are used as research strategy in this thesis, and the method to conduct the research is based on telephone interviews for the primary (qualitative) data, and documents and desk research for the secondary (quantitative) data. The gathered data is analyzed and designed in a way that allows the usage of comparative analysis technique to present the findings and draw conclusions. The results showed that new established Ikea retail store outside the city boundaries results with many effects on the city center and on the neighboring municipalities as well. The city center seems not to be affected negatively, but on the contrary positive effects were witnessed in both regions, these positive effects are linked to the increase inflow of customers from the external retail area which is known as spillover effect. III On the other hand, the neighboring towns and municipalities are more negatively affected especially with the trade of con-convenience goods as the consumers in these towns and municipalities start to go to the area of Ikea and the large external retail center to do their purchasing, the substitution effect is then said to be occurred. Moreover, the further far municipalities do not seem to be significantly affected by the establishment of Ikea. These effects whether positive or negative could be monitored by looking to few trade parameters such as the turnover, the sales index, and the consumers’ expenditure, these parameters can be very useful to measure the developments and changes in the trade and retail in a given place. 

How to manage macroeconomic policies to foster growth and employment and prevent financial and external crises

My presentation focuses on the implementation of a macroeconomic policy regime which, I believe, is capable of simultaneously attaining several targets, including the promotion of growth and employment and the prevention of external and financial crises.

Foreign support, internal political disputes and mass killings

This paper studies the incentives underlying the relations between foreign countries and rival domestic groups. It models the interaction in a infinitely-repeated game between these three players. The domestic groups bargain for a split of the domestic surplus and may engage in violent dispute for power and in unilateral mass killing processes. The foreign country may choose to support one of these groups in exchange for monetary transfers. The paper characterizes the parametric set in which strategies leading to no violent disputes nor mass killings are Subgame Perfect Nash Equilibra in the presence of foreign support, but not in its absence.

Orientation and external morphology of burrows of the mangrove crab Ucides cordatus (Crustacea: Brachyura: Ucididae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Artificial neural networks for load flow and external equivalents studies

In this paper an artificial neural network (ANN) based methodology is proposed for (a) solving the basic load flow, (b) solving the load flow considering the reactive power limits of generation (PV) buses, (c) determining a good quality load flow starting point for ill-conditioned systems, and (d) computing static external equivalent circuits. An analysis of the input data required as well as the ANN architecture is presented. A multilayer perceptron trained with the Levenberg-Marquardt second order method is used. The proposed methodology was tested with the IEEE 30- and 57-bus, and an ill-conditioned 11-bus system. Normal operating conditions (base case) and several contingency situations including different load and generation scenarios have been considered. Simulation results show the excellent performance of the ANN for solving problems (a)-(d). (C) 2010 Elsevier B.V. All rights reserved.

Duffin-Kemmer-Petiau and Klein-Cordon-Fock equations for electromagnetic, Yang-Mills and external gravitational field interactions: proof of equivalence

Starting from the Generating functional for the Green Function (GF), constructed from the Lagrangian action in the Duffin-Kemmer-Petiau (DKP) theory (L-approach) we strictly prove that the physical matrix elements of the S-matrix in DKP and Klein-Gordon-Fock (KGF) theories coincide in cases of interacting spin O particles with external and quantized Maxwell and Yang-Mills fields and in case of external gravitational field (without or with torsion), For the proof we use the reduction formulas of Lehmann, Symanzik and Zimmermann (LSZ). We prove that many photons and Yang-Mills particles GF coincide in both theories too. (C) 2000 Elsevier B.V. B.V. All rights reserved.

Arteriovenous fistula between the right internal mammary artery and the subclavian vein: percutaneous closure with detachable ballooncatheter embolization

A case of iatrogenic fistula from the right internal mammary artery to the subclavian vein following subclavian vein catheterization is reported. The patient had undergone percutaneous Intracath catheterization of the subclavian vein to treat hypovolemic shock during the surgical treatment of ectopic pregnancy. She had remained symptom-free for 7 years and then started to complain of effort dyspnea. The patient was found to have a thrill and a bruit at the subclavian region, and arteriography demonstrated a fistula between the right internal mammary artery and the subclavian vein. The fistula was successfully closed by embolization with a percutaneous detachable balloon catheter. © 1993.