1,719 research outputs found
Measuring the "Ideas" Production Function: Evidence from International Patent Output
This paper estimates the parameters of the ideas' production function central to recent models of economic growth. We do so by evaluating the determinants of international' patenting rates across the OECD, where an international patent is one granted by the U.S. patent office to a foreign establishment. Taking advantage of variation in the flow of ideas produced by different countries over time, we provide evidence for three main findings. First, at the level of the production of international patents, country-level R&D productivity increases proportionally with the stock of ideas already discovered, a key parametric restriction associated with the Romer model of ideas-driven growth (Romer, 1990; Jones, 1995). Second, we find that ideas productivity in a given country is constant or declining in the worldwide stock of ideas. Ideas production by other countries raises the bar for producing new-to-the-world technology domestically, outweighing the positive effects of international knowledge spillovers. Finally, ideas productivity is concave in the size of the R&D workforce and the linkage between ideas production and overall productivity growth is small. These results suggest that while the parametric restrictions required to generate endogenous technological change may be satisfied for individual economies, the growth rate associated with such effects may be modest. There seems to be a gap between the the sustained production of ideas by advanced economies and the ability to translate ideas into measured productivity growth.
The Determinants of National Innovative Capacity
Motivated by differences in R&D productivity across advanced economies, this paper presents an empirical examination of the determinants of country-level production of international patents. We introduce a novel framework based on the concept of national innovative capacity. National innovative capacity is the ability of a country to produce and commercialize a flow of innovative technology over the long term. National innovative capacity depends on the strength of a nation's common innovation infrastructure (cross-cutting factors which contribute broadly to innovativeness throughout the economy), the environment for innovation in its leading industrial clusters, and the strength of linkages between these two areas. We use this framework to guide our empirical exploration into the determinants of country-level R&D productivity, specifically examining the relationship between international patenting (patenting by foreign countries in the United States) and variables associated with the national innovative capacity framework. While acknowledging important measurement issues arising from the use of patent data, we provide evidence for several findings. First, the production function for international patents is surprisingly well-characterized by a small but relatively nuanced set of observable factors, including R&D manpower and spending, aggregate policy choices such as the extent of IP protection and openness to international trade, and the share of research performed by the academic sector and funded by the private sector. As well, international patenting productivity depends on each individual country's knowledge stock.' Further, the predicted level of national innovative capacity has an important impact on more downstream commercialization and diffusion activities (such as achieving a high market share of high-technology export markets). Finally, there has been convergence among OECD countries in terms of the estimated level of innovative capacity over the past quarter century.
Rural Community Participation, Social Networks, and Broadband Use: Examples from Localized and National Survey Data
Although attention has been given to how broadband access is related to economic development in rural areas, scant consideration has been given to how it may be associated with voluntary participation. This issue is important in that numerous studies have shown how much more vital community participation is in rural areas as compared to suburban and urban places. Drawing on three diverse data sets, we examine the influence of broadband access on community participation. In addition, we explore whether broadband access exerts its influence through, in conjunction with, or independent of social networks. The results suggest that broadband access and social network size have independent effects on volunteering in rural places.rural sociology, social networks, broadband, digital inequality, volunteerism, Community/Rural/Urban Development, Research and Development/Tech Change/Emerging Technologies,
Social Progress Index 2014
Over the last half century, economic growth has lifted hundreds of millions out of poverty and improved the lives of many more. Yet it is increasingly evident that a model of development based on economic development alone is incomplete. A society which fails to address basic human needs, equip citizens to improve their quality of life, erodes the environment, and limits opportunity for its citizens is not succeeding. Economic growth without social progress results in lack of inclusion, discontent, and social unrest. A broader and more inclusive model of development requires new metrics with which policymakers and citizens can evaluate national performance. We must move beyond simply measuring Gross Domestic Product (GDP) per capita, and make social and environmental measurement integral to national performance measurement. Tracking social and environmental performance rigorously will inform and drive improvement in policy choices and investments by all stakeholders. Measuring social progress will also help to better translate economic gains into better social and environmental performance, which will unleash even greater economic success. The Social Progress Index aims to meet this pressing need by creating a holistic and robust measurement framework for national social and environmental performance that can be used by leaders in government, business and civil society at the country level as a tool to benchmark success, improve policy, and catalyze action. Our vision is a world in which social progress sits alongside economic prosperity as the twin scorecards of success
Individual differences in human path integration abilities correlate with gray matter volume in retrosplenial cortex, hippocampus, and medial prefrontal cortex
Humans differ in their individual navigational abilities. These individual differences may exist in part because successful navigation relies on several disparate abilities, which rely on different brain structures. One such navigational capability is path integration, the updating of position and orientation, in which navigators track distances, directions, and locations in space during movement. Although structural differences related to landmark-based navigation have been examined, gray matter volume related to path integration ability has not yet been tested. Here, we examined individual differences in two path integration paradigms: (1) a location tracking task and (2) a task tracking translational and rotational self-motion. Using voxel-based morphometry, we related differences in performance in these path integration tasks to variation in brain morphology in 26 healthy young adults. Performance in the location tracking task positively correlated with individual differences in gray matter volume in three areas critical for path integration: the hippocampus, the retrosplenial cortex, and the medial prefrontal cortex. These regions are consistent with the path integration system known from computational and animal models and provide novel evidence that morphological variability in retrosplenial and medial prefrontal cortices underlies individual differences in human path integration ability. The results for tracking rotational self-motion-but not translation or location-demonstrated that cerebellum gray matter volume correlated with individual performance. Our findings also suggest that these three aspects of path integration are largely independent. Together, the results of this study provide a link between individual abilities and the functional correlates, computational models, and animal models of path integration
Which Way Was I Going? Contextual Retrieval Supports the Disambiguation of Well Learned Overlapping Navigational Routes
Groundbreaking research in animals has demonstrated that the hippocampus contains neurons that distinguish betweenoverlapping navigational trajectories. These hippocampal neurons respond selectively to the context of specific episodes despite interference from overlapping memory representations. The present study used functional magnetic resonanceimaging in humans to examine the role of the hippocampus and related structures when participants need to retrievecontextual information to navigate well learned spatial sequences that share common elements. Participants were trained outside the scanner to navigate through 12 virtual mazes from a ground-level first-person perspective. Six of the 12 mazes shared overlapping components. Overlapping mazes began and ended at distinct locations, but converged in the middle to share some hallways with another maze. Non-overlapping mazes did not share any hallways with any other maze. Successful navigation through the overlapping hallways required the retrieval of contextual information relevant to thecurrent navigational episode. Results revealed greater activation during the successful navigation of the overlapping mazes compared with the non-overlapping mazes in regions typically associated with spatial and episodic memory, including thehippocampus, parahippocampal cortex, and orbitofrontal cortex. When combined with previous research, the current findings suggest that an anatomically integrated system including the hippocampus, parahippocampal cortex, and orbitofrontal cortexis critical for the contextually dependent retrieval of well learned overlapping navigational routes
Clusters and entrepreneurship
This article examines the role of regional clusters in regional entrepreneurship. We focus on the distinct influences of convergence and agglomeration on growth in the number of start-up firms as well as in employment in these new firms in a given region-industry. While reversion to the mean and diminishing returns to entrepreneurship at the region-industry level can result in a convergence effect, the presence of complementary economic activity creates externalities that enhance incentives and reduce barriers for new business creation. Clusters are a particularly important way through which location-based complementarities are realized. The empirical analysis uses a novel panel dataset from the Longitudinal Business Database of the Census Bureau and the US Cluster Mapping Project. Using this dataset, there is significant evidence of the positive impact of clusters on entrepreneurship. After controlling for convergence in start-up activity at the region-industry level, industries located in regions with strong clusters (i.e. a large presence of other related industries) experience higher growth in new business formation and start-up employment. Strong clusters are also associated with the formation of new establishments of existing firms, thus influencing the location decision of multi-establishment firms. Finally, strong clusters contribute to start-up firm survival
Hippocampus and retrosplenial cortex combine path integration signals for successful navigation
The current study used fMRI in humans to examine goal-directed navigation in an open field environment. We designed a task that required participants to encode survey-level spatial information and subsequently navigate to a goal location in either first person, third person, or survey perspectives. Critically, no distinguishing landmarks or goal location markers were present in the environment, thereby requiring participants to rely on path integration mechanisms for successful navigation. We focused our analysis on mechanisms related to navigation and mechanisms tracking linear distance to the goal location. Successful navigation required translation of encoded survey-level map information for orientation and implementation of a planned route to the goal. Our results demonstrate that successful first and third person navigation trials recruited the anterior hippocampus more than trials when the goal location was not successfully reached. When examining only successful trials, the retrosplenial and posterior parietal cortices were recruited for goal-directed navigation in both first person and third person perspectives. Unique to first person perspective navigation, the hippocampus was recruited to path integrate self-motion cues with location computations toward the goal location. Last, our results demonstrate that the hippocampus supports goal-directed navigation by actively tracking proximity to the goal throughout navigation. When using path integration mechanisms in first person and third person perspective navigation, the posterior hippocampus was more strongly recruited as participants approach the goal. These findings provide critical insight into the neural mechanisms by which we are able to use map-level representations of our environment to reach our navigational goals
Simple and accurate one-sided inference from signed roots of likelihood ratios
The authors propose two methods based on the signed root of the likelihood ratio statistic for one-sided testing of a simple null hypothesis about a scalar parameter in the presence of nuisance parameters. Both methods are third-order accurate and utilise simulation to avoid the need for onerous analytical calculations characteristic of competing saddlepoint procedures. Moreover, the new methods do not require specification of ancillary statistics. The methods respect the conditioning associated with similar tests up to an error of third order, and conditioning on ancillary statistics to an error of second order
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