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71.
The Färe‐Primont index is used to evaluate total factor productivity (TFP) change and its components for a sample of French suckler cow farms in grassland areas in 1985–2014. The results reveal an increase in TFP of 6.6 per cent over the whole observation period, with technological progress being the major source of productivity growth. Meanwhile, efficiency decreased. Farms experienced great technological progress from 1991 to 2000. From a methodological point of view, the comparison with results obtained with Malmquist indexes shows similar trends but different magnitudes, with the Malmquist index overestimating the TFP and technological changes compared to the Färe‐Primont index. In addition, the use of a sequential approach that restricts technological change to being positive or null allows for the precise calculation of technology changes, disregarding the effects of external conditions that are captured in efficiency changes. Finally, the estimation of full dimensional efficient facets (FDEFs) that guarantees the positivity of all shadow prices used to assess the mix efficiency component of TFP change is promising.  相似文献   
72.
The long-standing debate on the relationship between farm size and productivity has been generally limited by the range of farm sizes evaluated and the definition of productivity. In this paper we use data from three Brazilian agricultural censuses to address these issues. In particular, we introduce a wider distribution of farm sizes than presently available from the literature and we employ total factor productivity (TFP) as our performance measure. In doing so, we test which farm size class had the highest TFP levels in 1985 and 2006, how factor productivity growth varied within and across farm size classes between those years, and which policy or factor had the greatest productivity enhancing effect. When examining TFP growth, we move beyond the common decomposition into technical and efficiency changes by identifying the complete distribution of farm productivity performances. We find that by 2006 a U-shaped distribution of productivity over farm sizes had emerged. Considerable 1985–2006 TFP growth differences are prevalent; positive rates for the majority accompany stagnant or negative rates for some. Public education investments were associated with faster productivity growth regardless of farm size, while technical assistance’s positive effect and credit’s negative effect were associated with larger farm sizes. The role of specialization varied by size.  相似文献   
73.
Constraints related to the technical and socioeconomic aspects of adopting tomato varieties are well documented. However, preferences relating to the demand for this fruit are rarely studied. In fact, demand for the different varieties of tomatoes might be related to consumers’ preferences for the extrinsic (color, size) and intrinsic (taste, nutritive value, water content) characteristics specific to each variety. It is therefore indispensable to determine the characteristics of tomatoes preferred by consumers. We examine consumers’ preferences for tomato attributes among a sample of 600 consumers in four representative markets in the main cities in southern Benin. The study also identifies potential segments of consumers and the market shares of each profile for each segment. The study identifies four potential tomato market segments, two of which have a strong preference for local tomatoes, namely, those that can be conserved for long periods and those with a firm consistency.  相似文献   
74.
Like many emerging economies, the productive structure of the Paraguayan economy is not complex. It relies extensively on low value-added activities in the primary sector such as agriculture and cattle ranching. These activities have a lower return in terms of economic and social benefits than other potential productive activities and do not contribute to increasing capability accumulation. In this paper we present a tool to support the identification of strategic sectors and products which if taken advantage of, could leverage development through the accumulation of productive capabilities. Our guiding question is: Which productive sectors should be promoted to foster economic development in Paraguay through a transition towards a more complex economy? To answer this question, we use concepts from the Economic Complexity theory to identify new products and cluster them based on the Product Space methodology for the determination of potential products and combine it with the Analytic Hierarchy Process (AHP) for multicriteria analysis considering multiple criteria. In doing so, our proposed methodology contributes to both the Economic Complexity and the AHP literature. Through this combination, we tackle the multiplicity of juxtaposed criteria, which should be considered at the prioritization stage in the crafting of economic restructuring measures according to the country's capabilities. Our evaluation showed that the combination of the approaches is useful, and for Paraguay's case, it helped identify sectors, which, if promoted by policymakers, could help boost economic development through complexity and capability accumulation.  相似文献   
75.
ABSTRACT

A key question for promoting international competition is how to improve the position of countries and industries in global value chains (GVCs). The first step is to properly measure industrial upgrading in GVCs. This is not a trivial issue because upgrading has not been defined unambiguously. Several authors have used different (and sometimes related) measures, all of which indicate certain aspects of upgrading. Rather than trying to find the single, ultimate measure of upgrading, we propose a different approach. We examine the multidimensionality of industrial upgrading, using eight indicators in factor analysis. Four of the eight indicators adopt the GVC perspective and include, for example, the growth of the share in value-added exports. We provide three quantitative dimensions of industrial upgrading: process upgrading, product upgrading, and skill upgrading. With these dimensions, we compare and analyze the upgrading of different countries and industries using the World Input–Output Database.  相似文献   
76.
Retailers frequently use exaggerated price discount advertisements with a tensile price claim (TPC; e.g., “Save up to 70%”) to attract consumers because they expect that once consumers enter a store, they will purchase low‐ or medium‐discounted products. Drawing on the selective accessibility model, this study investigated the way in which an implausibly high maximum level of savings stated in a TPC influences consumers’ expected price discount (EPD) and perceptions of actual price discounts across different types of TPCs (i.e., TPC stating a maximum level and TPC stating a range of savings). This study also investigated two situations in which consumers have previous knowledge of a product’s price discount versus when they have less or no knowledge of the discount. For both conditions, a single‐anchor TPC (i.e., “Save up to Y%”) that stated an implausible maximum level of savings led to a higher EPD and lower perceptions of the deal (i.e., perceived savings, price fairness, and perceived value) with respect to the actual price discount than did a TPC with a plausible maximum level of savings. In contrast, when the TPC stated two anchors (i.e., “Save XY%”) and consumers had knowledge of the price discount, their EPDs assimilated only toward the plausible anchor (X), and ignored the implausibly high maximum price discount (Y), resulting in a lower EPD and higher perceptions of the deal of the actual price discounts than a TPC that stated a plausibly high maximum level of savings. In contrast, when consumers had no knowledge of the price discount, their EPDs only adjusted toward the more plausible anchor (X), regardless of whether they perceived the maximum anchor as plausible or implausible. Thus, there was no difference in consumers’ perceptions of “Save XY%” between implausibly and plausibly high Y%.  相似文献   
77.
Recent empirical assessments revealed that footprint indicators calculated with various multi-regional input–output (MRIO) databases deliver deviating results. In this paper, we propose a new method, called structural production layer decomposition (SPLD), which complements existing structural decomposition approaches. SPLD enables differentiating between effects stemming from specific parts in the technology matrix, e.g. trade blocks vs. domestic blocks, while still allowing to link the various effects to the total region footprint. Using the carbon footprint of the EU-28 in 2011 as an example, we analyse the differences between EXIOBASE, Eora, GTAP and WIOD. Identical environmental data are used across all MRIO databases. In all model comparisons, variations in domestic blocks have a more significant impact on the carbon footprint than variations in trade blocks. The results provide a wealth of information for MRIO developers and are relevant for policy makers designing climate policy measures targeted to specific stages along product supply chains.  相似文献   
78.
Objective: In Japan, the National Immunization Program (NIP) includes PPV23 as the primary vaccination for adults and catch-up cohorts. The Japanese Association for Infectious Diseases recommends revaccination for older adults who received primary vaccination ≥5 years earlier. The cost-effectiveness of adding revaccination and/or continuing catch-up vaccination in the NIP was evaluated from the public payer perspective in Japan.

Methods: The Markov model included five health states: no pneumococcal disease, invasive pneumococcal diseases (IPD), non-bacteremic pneumococcal pneumonia (NBPP), post-meningitis sequelae, and death. Cohorts of adults aged 65–95 were followed until age 100 or death: 2014 cohort (aged 65–95, vaccinated: 2014); 2019 cohort (aged 65: 2019); and 2019 catch-up cohort (aged 70–100: 2019, unvaccinated: 2014). Strategies included: (1) vaccinate 2014 and 2019 cohorts; (2) vaccinate 2014 and 2019 cohorts and revaccinate both; (3) strategy 1 and vaccinate 2019 catch-up cohort; (4) strategy 2 and vaccinate 2019 catch-up cohort; and (5) strategy 4 and revaccinate 2019 catch-up cohort. Parameters were retrieved from global and Japanese sources, costs and QALYs discounted at 2%, and incremental cost-effectiveness ratios (ICERs) estimated.

Results: Strategy 1 had the highest number of IPD and NBPP cases, and strategy 5 the lowest. Strategies 3–5 dominated strategy 1 and strategy 2 was cost-effective compared to strategy 1 (ICER: ¥1,622,153 per QALY gained). At a willingness-to-pay threshold of ¥5 million per QALY gained, strategy 2 was cost-effective and strategies 3–5 were cost-saving compared to strategy 1.

Conclusions: Strategies including revaccination, catch-up, or both were cost-effective or cost-saving in comparison to no revaccination and no catch-up. Results can inform future vaccine policies and programs in Japan.  相似文献   
79.
The exploration of option pricing is of great significance to risk management and investments. One important challenge to existing research is how to describe the underlying asset price process and fluctuation features accurately. Considering the benefits of ensemble empirical mode decomposition (EEMD) in depicting the fluctuation features of financial time series, we construct an option pricing model based on the new hybrid generalized autoregressive conditional heteroskedastic (hybrid GARCH)-type functions with improved EEMD by decomposing the original return series into the high frequency, low frequency and trend terms. Using the locally risk-neutral valuation relationship (LRNVR), we obtain an equivalent martingale measure and option prices with different maturities based on Monte Carlo simulations. The empirical results indicate that this novel model can substantially capture volatility features and it performs much better than the M-GARCH and Black–Scholes models. In particular, the decomposition is consistently helpful in reducing option pricing errors, thereby proving the innovativeness and effectiveness of the hybrid GARCH option pricing model.  相似文献   
80.
The “industry nurturing agriculture” reforms and World Trade Organization accession led to dramatic growth in public expenditure and international trade in China’s agricultural sector. This article aims to estimate the effects of public expenditure and trade on agricultural productivity in China for 2004–2015. A semi-parametric production function with shape constraints is introduced to derive more accurate productivity before the productivity determinants are analyzed with an emphasis on public expenditure and trade. The empirical result shows that public expenditure and exports can effectively improve agricultural productivity, while imports have no significant effects. Policy implications are discussed in the context of supply-side reforms.  相似文献   
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