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A total of 289 studies of returns to agricultural R&D were compiled and these provide 1821 estimates of rates of return. After removing statistical outliers and incomplete observations, across the remaining 1128 observations the estimated annual rates of return averaged 65 per cent overall — 80 per cent for research only, 80 per cent for extension only, and 47 per cent for research and extension combined. These averages reveal little meaningful information from a large body of literature, which provides rate-of-return estimates that are often not directly comparable. This study was aimed at trying to account for the differences. Several features of the methods used by research evaluators matter, in particular assumptions about lag lengths and the nature of the research-induced supply shift.  相似文献   
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As patents and other forms of intellectual property become more pervasive in the next generation of biotechnologies, designing policies and practices to ensure sufficient freedom to operate (i.e., the ability to practice or use an innovation) will be crucial for non–profit research agencies, especially those intent on developing technologies destined for commercial release. Are non–profit organisations exempt from intellectual property claims? What constitutes infringement of a patent? How does a non–profit establish its freedom to operate? We address these issues in this paper and evaluate various options for accessing other people’s technologies. Options include cross–licensing agreements, research–only or cost–free licences, market segmentation strategies, mergers or joint ventures, and patent pooling or clearinghouse mechanisms. Responding creatively to the new intellectual property environment will have far reaching consequences for the future of non–profit research.  相似文献   
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Annual data for forty-eight states are used to account for changes in the composition of input and output aggregates over space and time, and thereby to obtain new evidence on changes in inputs, outputs, and productivity in U.S. agriculture. The measures change significantly when we use state-specific rather than national prices and when we allow for changes in the composition of the aggregates, especially of labor and capital inputs. We compare our estimates and those reported by Ball et al. ( American Journal of Agricultural Economics 81(1999):164–79). The national estimates are similar but substantial differences are found in state-level productivity growth.  相似文献   
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Governments everywhere are trimming their support for agricultural R&D, giving greater scrutiny to the support that they do provide, and reforming the public agencies that fund, oversee, and carry out the research. This represents a break from previous patterns, which had consisted of expansion in the public funds for agricultural R&D. Private-sector spending on agricultural research has slowed along with the growth of public spending in recent years, but the balance continues to shift towards the private sector. This article presents a quantitative review of these funding trends and the considerable institutional changes that have accompanied them. We discuss new data for 22 OECD countries, providing institutional details for five of these countries, and conclude with an assessment of policy developments.  相似文献   
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Notwithstanding the ambiguous research and productivity promoting effects of plant variety protections (PVPs) even in developed countries, many developing countries have adopted PVPs in the past few years, in part to comply with their Trade‐Related Aspects of Intellectual Property Rights (TRIPS) obligations. Seeking and maintaining PVPs reserves options to an expected revenue stream from the future sale of protected varieties, the value of which varies for a host of reasons. In this article we empirically examine the pattern of PVP applications in China since its PVP laws were first introduced in 1997. We place those PVP rights in the context of China's present and likely future seed markets to identify the economic incentives and institutional influences on decisions to develop and apply for varietal rights.  相似文献   
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This article provides an overview of how recent advances in machine learning and the availability of data from earth observing satellites can dramatically improve our ability to automatically map croplands over long periods and over large regions. It discusses three applications in the domain of crop monitoring where machine learning (ML) approaches are beginning to show great promise. For each application, it highlights machine learning challenges, proposed approaches, and recent results. The article concludes with discussion of major challenges that need to be addressed before ML approaches will reach their full potential for this problem of great societal relevance.  相似文献   
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Zvi Griliches’ seminal analysis of hybrid corn spawned a large literature seeking to quantify and demonstrate the value of agricultural research and development (R&D) investments. The most important metric for quantifying the rate of return to R&D emerging from this literature is the internal rate of return (IRR), even though Griliches was sceptical of its usefulness as a metric in this context. An alternative metric, also reported by Griliches but not as commonly used in the subsequent returns‐to‐research literature, is the benefit–cost ratio (BCR). We assess how the implications of the returns to agricultural R&D literature may have differed if the BCR had become the standard rather than the IRR. We reveal that the IRR and BCR produce substantially different rankings of agricultural R&D projects, differences that persist even under various commodity and geographical aggregations of the BCR and IRR estimates. The median across 2,627 reported IRRs is 37.5 per cent per year. Using data gleaned from 492 research evaluation studies, we developed and deployed a methodology to impute 2,126 BCRs (median of 5.4) and modified internal rates of returns (MIRRs, median of 16.4 per cent per year) assuming a uniform 10 per cent per year discount rate and a 30 year research timeline.  相似文献   
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Reported rates of return to agricultural R&D are generally high, but they are likely to be biased, particularly because of attribution problems—mismatching research benefits with costs. The importance of attribution biases is illustrated here with new evidence for Brazil. During 1981–2003, varietal improvements in upland rice, edible beans, and soybeans yielded benefits of $14.8 billion in present value (1999 prices) terms. Attributing all of the benefits to Embrapa, a public research corporation accounting for more than half of Brazil's agricultural R&D spending, the benefit-cost ratio would be 78:1. Under alternative attribution rules, the ratio drops to 16:1.  相似文献   
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