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201.
Academic research has identified a broad array of resources that exist in communities that have an established technology-based entrepreneurial venture population. These studies have focused upon well-known areas such as the Silicon Valley, the 128 loop in Boston and Austin, Texas. Yet even in these relatively homogeneous environments the studies have been highly inconsistent in their findings as to what bundle of resources might be critical in attracting new ventures. Many other communities have either been unsuccessful or only marginally successful in their efforts to recreate the magic of Silicon Valley. We utilize a Resource-Based model to suggest that communities develop unique bundles over time and that the development of these bundles in a particular geographic area is neither linear nor easily replicable.JEL Classification: 01, 021, 03, R11, R58  相似文献   
202.
Outside invention has gained in importance as universities are actively seeking commercialization of their inventions since the passage of the Bayh-Dole Act. The paper analyzes the incentives to invent for outside and inside inventors. It is shown that outside inventors have greater incentives to invent than incumbents. Outside inventors can always fully appropriate the gains from invention irrespective of market structures and firm behaviour. Moreover, outside invention prompts incumbents to commercialize an invention in contrast to inside invention. Embryonic inventions could best be commercialized by new enterprises due to the uncertainty of their outcomes. Cooperative invention could boost consumer welfare but constitutes a lackluster incentive to invent.  相似文献   
203.
In the course of the liberalization of European energy markets, the German government opted—diverging from all other European countries—for Negotiated Third-Party Access. In this article we analyze if, theoretically, this institutional regime can be superior to regulation. We review empirically whether certain aspects of the actual implementation, in particular publication of the network access charges for each network supplier, facilitated or inhibited competition. In the first place we reconsider previous research, showing that NTPA can—under certain conditions—be economically effective. Our empirical analysis shows that the duty of publishing access charges supported market transparency and imposed a regulatory threat, particularly to suppliers with significantly above-average charges. On the other hand observable price adjustments over time serve as an indicator of tacit collusion. Although the expensive suppliers cut their prices, the cheaper ones raised theirs.We thank Maik Heinemann, Joachim Wagner and two anonymous referees for helpful comments and the Lower Saxonian Ministry of Science and Culture for financial support.JEL Classification: D42, L43, L94  相似文献   
204.
This paper evaluates the short-run benefits of research and development (R&D) projects funded by the Automotive Lightweighting Materials (ALM) Program of the Office of FreedomCAR and Vehicle Technologies of the U.S. Department of Energy (DOE). The six ALM projects evaluated—using qualitative and quantitative evaluation methods—yielded numerous benefits in the short-run. From the qualitative assessment, all met their technical goals, increased intellectual knowledge among the research teams, and led to increased collaboration among DOE, the auto industry, its suppliers, and national laboratories. Moreover, U.S. competitiveness appeared to have increased as a result of each R&D effort. One interesting finding, however, is that most of the participants indicated their firms would not have engaged in the research efforts without DOE funding. If they had engaged in the effort, it would have been with considerably less person time and financial commitment. With respect to quantitative measures, several graduate students were supported by the projects and numerous publications and presentations resulted, although these metrics varied across the ALM R&D projects.  相似文献   
205.
This article based, on 38 in-depth interviews with Rotterdam cocaine retail dealers, aims to present a clearer picture of how cocaine supply lines in the Netherlands are organized in order to fine-tune policy with respect to crime, public order and safety on the different trade levels. On the retail level the market for cocaine is strictly separated in a market for crack cocaine versus a market for powder cocaine. The crack dealers are often hard drug users themselves living in relatively poor circumstances. Although dealing cocaine is their main activity, they tend to be involved in other activities related to the drug scene, e.g. smuggling cocaine via Amsterdam airport. The cocaine distribution line for supply on the local market is seldom more than two steps. Because the supply for the Rotterdam cocaine retailers comes mainly from small-scale imports, successful police operations against large-scale imports of cocaine will have little influence on the local cocaine supply in the Netherlands.  相似文献   
206.
The present study involved a multimethod assessment of impulsivity among 86 men. Using two questionnaires and four performance-based measures of impulsivity, the factor structure of the impulsivity data was examined. Four constructs that theoretically mediate the relationship between impulsivity and husband violence (i.e., substance abuse, anger/hostility, marital dissatisfaction, and psychological abuse) were assessed to examine a mediational model predictive of husband violence. Substance abuse and marital dissatisfaction mediated the relationship between impulsivity and psychological abuse. Psychological abuse mediated the relationship between substance abuse and marital dissatisfaction and husband violence. Although anger/hostility was not a mediator, there were bivariate associations between anger/hostility and impulsivity, psychological abuse, and husband violence. The results of the regression analyses were virtually identical when controlling for the effect of intelligence on the model variables. The implications of the findings for the assessment of impulsivity and for future husband violence research are discussed.  相似文献   
207.
Eighty heterosexual dating couples provided information about their gender, individual histories of abuse in their current relationship, attachment styles, perception of and satisfaction with relationship power. Partner report of physical abuse was the dependent variable. APIM actor results suggest that an individual's gender interacts with perceived level of relationship power and satisfaction with relationship power for physical abuse. Both dimensions of attachment interacted with perceived relationship power for physical abuse. Partner effects were also found. One's partner's sex interacted with perceived power and satisfaction with relationship power. Finally, the partner's avoidant attachment interacted with satisfaction with relationship power. These findings generally replicate and extend the work of H. M. Ronfeldt, R. Kimerling, and I. Arias (1998, J. Marriage Fam. 60: 70–78) by showing how attachment styles, perception of relationship power, and satisfaction with relationship power are related in predicting aggression against a romantic partner.  相似文献   
208.
Violence and Aggression in the Lives of Homeless Children   总被引:1,自引:0,他引:1  
The present research examined the role of violence and aggression in the lives of children in homeless families, focusing on possible connections among family violence, children's aggression, and children's problems with social isolation and rejection. Measures were obtained from structured interviews with 93 sets of mothers and children. Consistent with past research, average estimates of specific violent incidents experienced by mothers (as adults) were quite high. Measures of this family violence were reliably correlated with children's behavior problems as well as with measures of aggression in peer relationships (victimization, ease of resolving fights with friends).Finally, results of regression analyses were most consistent with a model in which family violenceand economic distress contributed to problematic aggressive behaviors among children; that aggression, in turn, appeared to lead to social isolation and avoidance. The overall results emphasized the need to address violence and aggression in any intervention programs for homeless children and families.  相似文献   
209.
Detecting Spatial Movement of Intra-Region Crime Patterns Over Time   总被引:1,自引:0,他引:1  
Many of the traditional measures of the degree to which crime patterns change over space and time have limitations. In particular most are unable to determine any change in spatial crime pattern within an areal unit. Usually studies measure the change in crime levels in contiguous areas (expressed as discrete sub-divisions of a study area), but this can become problematic due to difficulties such as the Modifiable Areal Unit Problem (MAUP). This paper describes a technique developed to allow researchers to examine intra-study region changes in crime patterns between two time periods without the need to aggregate crime counts to within-city areal boundaries. The method presented uses a random point nearest neighbor test combined with a Monte Carlo simulation. The process resolves problems of patterning and the MAUP that are common with a number of spatial displacement and pattern movement studies. This technique is demonstrated with example data from a city-wide police burglary crackdown in the Australian capital.  相似文献   
210.
Using data from the Cambridge Study in Delinquent Development, a prospective longitudinal study of 411 London males, the main aim of this research is to compare the age of onset of six types of offenses according to different methods of measurement – prospective self-reports, retrospective self-reports, and official records – and also to explore self-reported and official onset sequences. Results showed that ages of onset reported in retrospective accounts generally tended to be higher than those reported prospectively. Agreement rates between prospective and retrospective accounts were lowest for minor forms of offending, and highest for more serious offenses such as theft of vehicles. Males with heavy substance use habits were less likely to report the same age of onset retrospectively compared with prospectively. Denial rates were substantial in all comparisons, particularly for minor forms of offending. Comparisons between self-reported and official measures of onset revealed that there was a greater degree of agreement between the two measures for serious offenses. Whereas self-reported onset sequences suggested that minor crimes were committed before more serious offenses, official onset sequences suggested the reverse. The findings show that retrospective reports are not suitable to address research questions requiring detailed information (i.e., most criminal career parameters: age of onset, frequency, age of termination, etc.), for studying minor forms of offending, and for samples of individuals with serious substance use habits. Furthermore, official measures of offending can also produce misleading results, particularly when studying minor forms of offending.  相似文献   
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