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11.
Research Summary: We combine the absorptive capacity and social network theory approaches to predict how intrafirm “whole” network characteristics affect the firm's speed of absorption of external knowledge to produce inventions. We start from the widely accepted view that distant, externally‐developed knowledge is difficult to absorb into the focal firm's own knowledge production. We suggest that high levels of intrafirm inventor task network diversity and task network density are essential for a diversity of knowledge inputs and coordinated actions regarding knowledge transfer, which in turn, reduces problems related to the absorption of knowledge—especially in the case of knowledge that is distant from the focal firm. The results of an event history study of 113 pharmaceutical firms that engaged in technology in‐licensing from 1986 to 2003 provide general support for our hypotheses. Managerial Summary: Firms keen to keep up with an uncertain and ever‐changing industry environment, can benefit from the speedy introduction of inventions. We examine how firms absorb licensed‐in technologies to nurture the rapid development of own related inventions. We show that a firm's absorption speed depends on the characteristics of the internal collaboration networks among the firm's inventor employees. More specifically, technologically diverse and well‐connected inventor networks improve the firm's ability to absorb external technologies quickly. This applies especially to externally acquired technologies that are unfamiliar to the firm. Depending on the distance of the acquired technology from the focal firm combined with speed‐inducing inventor network characteristics, our estimates suggest that firms can reduce the time needed for absorption by several months.  相似文献   
12.
We examine the quantile serial dependence in crude oil prices based on the Linton and Whang’s quantile-based portmanteau test which we improved by means of quantile wild bootstrapping (QWB). Through Monte Carlo simulation, we find that the quantile wild bootstrap-based portmanteau test performs better than the bound testing procedure suggested by Linton and Whang. We apply the improved test to examine the efficiency of two crude oil markets – WTI and Brent. We also examine if the dependence is stable via rolling sample tests. Our results show that both WTI and Brent are serially dependent in all, except the median quantiles. These findings suggest that it may be misleading to examine the efficiency of crude oil markets in terms of mean (or median) returns only. These crude oil markets are relatively more serially dependent in non-median ranges.  相似文献   
13.
This article aims to evaluate the production line automation projects developed by Brazilian and Colombian companies from the Project Management perspective, through the analysis of the application degree of PMBOK processes, to understand how formal techniques are being employed in these countries and also to identify improvement opportunities, when necessary. Data were collected through a survey. The similarity index between the ten processes, with the highest application degree in the Brazilian and Colombian samples, was 70%. For the processes with the lowest application degree, the similarity index was 60%. No similar study was found in the literature.  相似文献   
14.
15.
This paper uses a difference-in-difference methodology similar to the one originally proposed by Rajan and Zingales to test whether sovereign defaults hurt the more export-oriented industries disproportionately, and it finds strong support for this hypothesis. However, contrary to the findings of previous studies, our estimates suggest that the effect of defaults is short-lived.  相似文献   
16.
The paper analyzes the guarantee of the Federal National Mortgage Association (FNMA). Rather than try to price the guarantee, we used time-series estimates of its value from Kane and Foster to infer the behavior of FNMA in exploiting the guarantee. The results are consistent with a model that predicts that FNMA does not take as much risk as it might. Rather, it trades off risk and return, but it does increase risk and exploit the guarantee when it gets in trouble (as it did in 1981).We have received helpful research assistance from Peter Carr and Bruno Gerard.  相似文献   
17.
Personal preferences and financial incentives make homeownership desirable for most families. Once a family purchases a home they find it impractical (costly) to frequently change their ownership of residential real estate. Thus, by deciding how much home to buy, a family constrains their ability to adjust their asset allocation between residential real estate and other assets. To analyze the impact of this constraint on consumption, welfare, and post-retirement wealth, we first investigate an individual’s optimal asset allocation decisions when they are subject to a “homeownership constraint.” Next, we perform a “thought experiment” where we assume the existence of a market where a homeowner can sell, without cost, a fractional interest in their home. Now the housing choice decision does not constrain the individual’s asset allocations. By comparing these two cases, we estimate the differences in post-retirement wealth and the welfare gains potentially realizable if asset allocations were not subject to a homeownership constraint. For realistic parameter values, we find that the homeowner would require a substantial increase in total net worth to achieve the same level of utility as would be achievable if the choice of a home could be separated from the asset allocation decision. The robustness of the analysis is evaluated with respect to the model’s parameters and initial state variables. We find that changes in the values of the constraint (i.e., the value of the home) and the expected real rate of home value appreciation are the only state variables or parameter that is associated with a large change in asset allocation and/or the burden imposed by the housing constraint. This finding suggests the importance of a detailed examination of the impact of inter-regional differences in home prices and expected rates of appreciation on asset allocation and post-retirement wealth.  相似文献   
18.
We explore the effects of uncertainty on a firm that can respond by modifying its investment or production schedule (or both simultaneously) to variations in output price. Investment may increase capacity and/or reduce costs. We consider a firm with finite resources.Our model uses option theory instead of the more traditional net present value framework. One of the early papers using this approach is Brennan and Schwartz (1985) in which an investment project to extract a finite natural resource is valued. In that paper, the value of the firm is a function of two state variables, the finite resource to be extracted (output to be produced in the future) and the commodity spot price. In order to maximize firm value, the manager can respond by modifying one control variable, the production level. In our model we handle instead three state variables (spot price, resources, accumulated investment) and two control variables (production rate and investment rate), and solve numerically.We obtain both the value and the optimal policy of a firm that has investment projects that increase capacity and/or reduce costs and illustrate optimal policies as resources and available investments decrease over the life of the firm. Firms may start by only investing, then invest and produce, to end only producing.We thank Scott Wo, the referee and the editor for their comments and suggestions. Cortázar and Lowener acknowledge the financial support from FONDECYT and FONDER.  相似文献   
19.
Road traffic injuries in general and pedestrian injuries in particular are a major public health problem in Mexico, especially in large urban areas. Analysis of mortality and road crashes at the national level was done using routine data recorded on death certificates. Fatality rates for different age groups were estimated by region for the year 2000. These data were supplemented by a cross-sectional study of pedestrian injuries in Mexico City based on death certificates information for pedestrians who lived and died in Mexico City between 1994 and 1997. Participant observation of physical spaces where crashes occurred was carried out. The spaces were filmed and in-depth interviews of survivors conducted. Road traffic crashes were responsible for approximately 17,500 deaths in Mexico during 2000. The mean age of the victims was 37 years. Mexico lost an average of 30 years of productive life for each individual who died in a traffic crash – 525,000 years in 2000. An estimated 9500 (54.3%) of all fatalities were pedestrians, and for every pedestrian death there were 13 others who sustained nonfatal injuries requiring medical care. The overall crude mortality rate for pedestrian injuries in Mexico City was 7.14 per 100,000 (CI 6.85-7.42). A concentration of deaths was observed in 10 neighborhoods at specific types of street environments. The underlying factors included dangerous crossings and the absence or inadequacy of pedestrian bridges, as well as negative perceptions of road safety by pedestrians. In conclusion, this study demonstrates the importance of elucidating the underlying contextual determinants of pedestrian injuries.  相似文献   
20.
The paper examines the equity market price interaction between Australia and the European Union – represented by the UK, Germany and France – based on the Toda–Yamamoto causality test, which is bootstrapped with leveraged adjustments. A new information criterion is used to choose the optimal lag order. Weekly MSCI data covering the period 1988 to 2001 is used, divided into two subperiods to allow for a structural break arising from the ERM crisis of 1992. Results show that, during the period before the ERM crisis, no significant causal links exist between Australia and any of three EU countries. During the period after the ERM crisis, Australia also had no causal links with Germany and France but it had with the UK, with causality running from the UK to Australia but not vice-versa. Thus, Australian investors may find the German and French, but not the UK, equity markets, attractive venues for their international diversification. German and French, but not British, investors may also obtain the same benefit from the Australian equity market.  相似文献   
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