我国现阶段矿难频发成因及其对策:基于安全投入的视角

本文从安全经济学安全投入的视角探求我国现阶段矿难频发的原因。笔者认为，在理性经济人的假设下，由于安全投入的巨额性、安全收益的隐蔽性、收益实现的滞后性、安全事故的或然性、安全生产的外部性等因素的交错作用导致安全投入不足，从而引起矿难频发。据此，在全面分析我国安全投入不足的表现及成因的基础上，笔者提出了以煤矿企业为投入主体．中央政府、地方政府、金融机构协同筹资的“四位一体”方案。     

Human health and pesticide use in Sub‐Saharan Africa

While pesticides–such as insecticides, fungicides, and herbicides–are often promoted as inputs that increase agricultural productivity by limiting a range of pre‐harvest losses, their use may have negative human health and labor productivity implications. We explore the relationship between pesticide use and the value of crop output at the plot level and a range of human health outcomes at the household level using large‐scale, nationally representative panel survey data from four Sub‐Saharan African countries where more than 10% of main season cultivators use pesticides. We find that pesticide use is strongly correlated with increased value of harvest, but is also correlated with higher costs associated with human illness, including increased health expenditures and time lost from work due to sickness in the recent past. We take these results as suggestive that the findings of more targeted studies are indeed generalizable beyond their original, purposively chosen samples.     

Imported Intermediate Inputs and Firms’ Productivity Growth: Evidence from the Food Industry

Imported goods play a central role in determining the gains from trade. Using detailed trade and firm‐level data for Italy and France, we investigate the relationship between trade integration, imported intermediate inputs and firm performance in the food industry. Our main findings show that an increase in import competition spurs firm‐level productivity growth. Furthermore, the productivity growth effect attributable to imported intermediate inputs is significantly stronger than the effect due to imported final products. In addition, we find that new imported inputs are of particular importance, especially for Italian food firms, though less so for the French firms. Finally, the productivity growth effect of trade integration tends to be asymmetric across firms: more productive firms gain more from trade integration. These stylised facts have interesting policy implications.     

Análisis de costos y estrategias productivas en la lechería de pequeña escala en el periodo 2000–2012

An accounting analysis was performed on the evolution and performance of productive, economic and marketing strategies implemented by small-scale dairy farmers in the peri-urban area of Texcoco, Mexico. Economic and production records for 1 023 lactation were obtained in two periods, 2000 and 2012. The general cost methodology was used to establish the accounting structures of these production systems, and the re-adjustment of values financial methodology through calculating deflated values based on data from the Mexican National Index of Consumer Prices. Evidence is presented that farmers in Stratum I defined as strategies not hiring temporary or permanent labour, as well as independence in the purchase of inputs (this Stratum produces 90% of its inputs). Stratum II reduced 3 of the main 4 items of the total production cost (feeding, medicines and breeding) and increased the mean profit per litre of milk ($ 2.00 MXN) through selling strategies. Stratum III defined as their strategies increased productivity (59%), a reduction in the cost (29%) of the main input (feed) and taking advantage of their productive scale to obtain a higher receipt of revenues for the farm.     

A new methodology to measure efficiencies of inputs (outputs) of decision making units in Data Envelopment Analysis with application to agriculture

This paper aims at developing a new methodology to measure and decompose global DMU efficiency into efficiency of inputs (or outputs). The basic idea rests on the fact that global DMU's efficiency score might be misleading when managers proceed to reallocate their inputs or redefine their outputs. Literature provides a basic measure for global DMU's efficiency score. A revised model was developed for measuring efficiencies of global DMUs and their inputs (or outputs) efficiency components, based on a hypothesis of virtual DMUs. The present paper suggests a method for measuring global DMU efficiency simultaneously with its efficiencies of inputs components, that we call Input decomposition DEA model (ID-DEA), and its efficiencies of outputs components, that we call output decomposition DEA model (OD-DEA). These twin models differ from Supper efficiency model (SE-DEA) and Common Set Weights model (CSW-DEA). The twin models (ID-DEA, OD-DEA) were applied to agricultural farms, and the results gave different efficiency scores of inputs (or outputs), and at the same time, global DMU's efficiency score was given by the Charnes, Cooper and Rhodes (Charnes et al., 1978) [1], CCR78 model. The rationale of our new hypothesis and model is the fact that managers don't have the same information level about all inputs and outputs that constraint them to manage resources by the (global) efficiency scores. Then each input/output has a different reality depending on the manager's decision in relationship to information available at the time of decision. This paper decomposes global DMU's efficiency into input (or output) components' efficiencies. Each component will have its score instead of a global DMU score. These findings would improve management decision making about reallocating inputs and redefining outputs. Concerning policy implications of the DEA twin models, they help policy makers to assess, ameliorate and reorient their strategies and execute programs towards enhancing the best practices and minimising losses.     

Bargaining with independence of higher or irrelevant claims

This paper studies independence of higher claims and independence of irrelevant claims on the domain of bargaining problems with claims. Independence of higher claims requires that the payoff of an agent does not depend on the higher claim of another agent. Independence of irrelevant claims states that the payoffs should not change when the claims decrease but remain higher than the payoffs. Interestingly, in conjunction with standard axioms from bargaining theory, these properties characterize a new constrained Nash solution, a constrained Kalai–Smorodinsky solution, and a constrained Kalai solution.     

The probability of violating Arrow’s conditions

Arrow’s impossibility theorem shows that all preference aggregation rules (PARs) must violate a specific set of normative conditions (transitivity, Pareto, IIA, nondictatorship) over an unrestricted domain of preference profiles. However, the theorem does not address which PARs are more likely to violate those conditions across preference profiles. We compare the probabilities that thirteen PARs (anti-plurality, Hare, Nanson, plurality, plurality runoff, Simpson–Kramer, Baldwin, Borda, Coombs, Copeland, Dowdall, pairwise majority, and ranked pairs) violate Arrow’s conditions. We prove that Baldwin, Borda, Coombs, Copeland, Dowdall, and ranked pairs are less likely to violate IIA than the first six PARs, and they are less likely to violate Arrow’s conditions jointly. In contrast, pairwise majority never violates IIA but can violate transitivity. Simulations with three alternatives reveal that among the PARs studied, pairwise majority is the most likely to satisfy Arrow’s conditions jointly. Our results suggest pairwise majority violates transitivity with a small probability, while the other PARs violate IIA with much larger probabilities.     

Offshoring Brains? Evidence on the Complementarity between Manufacturing and R&D in Danish Firms*

By employing a firm-level linked employer–employee dataset for Danish manufacturing firms, this paper investigates whether offshoring is complementary to, or a substitute for, research and development (R&D) activities. Offshoring is instrumented with world export supply to circumvent the inherent endogenous nature of the firm's decision to offshore. Results suggest that firms with increased offshoring do in fact tend to engage in further R&D activities at home. Moreover, they also tend to reallocate R&D resources toward product R&D, possibly at the expense of process R&D.     

Perspectives of organizers and exhibitors on the performance assessment of exhibitors at an International Travel Fair

Travel fairs contributed to the booming tourism industry around the world, but the extant research rarely assessed the performance of them, not to mention individual exhibitor’s performance. This study uses the resource-based theory and the metafrontier-to-data envelopment analysis at annual International Travel Fairs. This study administered a questionnaire survey to collect two-year data on the resources consumed and the outputs generated from observed exhibitors. The results from a quadrant-based (Quantitative-return on objectives (QROO) vs. efficiency) matrix and a slack-value analysis indicated that more can be gained from less for tourism and hospitality exhibitors. Booth area, rental fee, set up cost and number of on-site staff should be less to benefit performance from this study. The results serve as a decision-making reference for the organizer to screen out inefficient exhibitors when booths are in short supply as well as offering the exhibitors’ improvement direction. Implications and future research are discussed.     

Trade liberalization induced profitability enhancement? The impact of intermediate input imports on firm profitability

Using the detailed data on production and transaction of Chinese manufacturing firms, we investigate how the input tariff liberalization affects firm profitability and explore the underlying channels of this effect. We find that input tariff reduction significantly increases firms’ profitability. Our finding is robust to a variety of specifications. We further find that the quality upgrading of imported intermediate inputs and the reduction of inventory costs are the main reasons for the profit-enhancing effect of input tariff reduction. Our study has important policy implications for the economic growth in the long run and the economic recovery during the epidemic of COVID-19.