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51.
In this study, we consider Bayesian methods for the estimation of a sample selection model with spatially correlated disturbance terms. We design a set of Markov chain Monte Carlo algorithms based on the method of data augmentation. The natural parameterization for the covariance structure of our model involves an unidentified parameter that complicates posterior analysis. The unidentified parameter – the variance of the disturbance term in the selection equation – is handled in different ways in these algorithms to achieve identification for other parameters. The Bayesian estimator based on these algorithms can account for the selection bias and the full covariance structure implied by the spatial correlation. We illustrate the implementation of these algorithms through a simulation study and an empirical application.  相似文献   
52.
The paper investigates whether patent fees are an effective mechanism to deter the filing of low‐quality patent applications. The study analyzes the effect on patent quality of the Patent Law Amendment Act of 1982, which resulted in a substantial increase in patenting fees at the U.S. Patent and Trademark Office. Results from a series of difference‐in‐differences regressions suggest that the increase in fees led to a weeding out of low‐quality patents. About 10% of patents in the lowest quality decile were filtered out, with the effect concentrated in the patents of firms whose overall patent portfolio was medium to large (more than 20 patents). The study has strong policy implications in the current context of concerns about declines in patent quality.  相似文献   
53.
We examine factors affecting the adoption of improved cassava varieties of 217 households in the Cauca Department in southwest Colombia. Using DNA fingerprinting through Single Nucleotide Polymorphisms (SNPs), we identified different cultivars in farmers fields. We also used this information to remove possible bias in the adoption model that could have resulted from a misclassification of improved varieties (IVs). As a result, we found that farmers substantially overestimate their use of IVs and there are important differences in the determinants of adoption between farmer self‐identification and DNA fingerprinting. This finding implies that the incorporation of DNA fingerprinting in IV adoption studies is important to ensure the accuracy of future agricultural economic research and the relevance of subsequent policy recommendations.  相似文献   
54.
We investigate the roots of scientists' perceptions of the impact of their work by examining stable psychological characteristics such as personality traits. An analysis of personality traits highlights the effects of policies related to gender equality, allocation of research time and skills acquisition. It improves our understanding of the conflicts related to scientists’ perceptions of the impact of their research on beneficiaries. For example, conscientiousness increases the perceived impact on clinical beneficiaries, but reduces the perceived impact on industrial beneficiaries. Organizational scientific freedom increases the effects of personality traits on perceived impact on beneficiaries such that scientists affiliated to a university are less likely than colleagues working in other research settings to perceive the simultaneous impact of their work on both industrial and clinical beneficiaries.  相似文献   
55.
This paper analyzes the uneven processes underpinning industrial relations policy liberalization in New Zealand, Australia, the UK, and Ireland. Drawing upon 140 elite interviews and building upon ideational comparative political theories, the paper highlights the role of ideas in the policy change process. It identifies how particular ideas can be used to construct policy problems, how these ideas can gain legitimacy through battles with competing ideas, and how policy legacies can influence whether ideas take root. The findings from the comparative case analysis expose a critical difference between “positive legacies” and “negative legacies” to account for different liberalization trajectories.  相似文献   
56.
Khat-chewing, a controversial leisure activity within the Somali diaspora in Britain, has received little attention within the academic field of Leisure Studies. This paper reports on ethnographic research to provide insights into the unique locations where young British-Somali men chew khat, exposing the liminal qualities of such localities. The paper begins with an overview of the contentious position khat-chewing occupies within Somali communities in Britain, highlighting reasons why young British-Somali men hide their association with the leisure practice. The discussion that follows considers how young male khat users conceptualise spatial environments, exposing how these locations temporarily produce a dual sense of privacy and sociality. The ambiences of such temporary leisure spaces remain open to the prospect of discovery, resulting in the use of discretionary tactics to maintain a sense of secrecy. In this context, we discuss how khat-chewing offers a sense of cultural identity and belongingness while also marking young British-Somali men as outsiders – even within their own communities.  相似文献   
57.

Recent calls for using the antitrust laws to break up the large Internet giants are misplaced for a number of reasons. First, similar efforts against oil, tobacco, motion-picture, and telecommunications monopolies have not proved to be beneficial to economic welfare. Second, the failure to break up Microsoft using Section 2 has not proved to be a mistake: competition in operating systems and Internet browsers has flourished recently. Finally, a Section 2 case against Amazon, Facebook, or Google could not succeed if it focused on the digital advertising market. Even in a case based on market power on the other side of their platforms, a structural remedy—a break-up—would not improve economic welfare in the long run.

  相似文献   
58.
Since December 2015, the Federal Reserve has operated a new “floor system” in which it brings about desired changes in its targeted federal funds rate by managing the interest rate it pays on bank reserves and other short‐term liabilities. The design of this new system reflects the tendency of Fed officials to view monetary policy as affecting the economy through Keynesian” interest rate channels. From this Keynesian perspective, policy actions that change the size of the balance sheet are seen as tools for influencing credit market conditions that operate in addition to and independently of the Fed's monetary policy stance. The alternative monetarist framework proposed by the author views monetary policy and its effects as operating through the interaction between money supply and demand. Use of this framework makes clear that, even under a floor system, monetary policy actions designed to affect the aggregate price level and the rate of inflation must be accompanied sooner or later by traditional open market operations that have implications for the size and composition of the Fed's balance sheet. Use of the monetarist framework also underscores the likelihood that the Fed, by paying interest on reserves, has unknowingly contributed to the restrictiveness of its own monetary policies since the financial crisis, a period during which inflation has run consistently below target. More generally, the monetarist framework downplays the importance of the zero lower interest rate bound and suggests that monetary policy could be conducted more effectively by adopting and adhering to a consistent, rule‐like manner during good times and bad.  相似文献   
59.
Differences among bidder type-specific outcomes of asset sales are theoretically related to differences in bidders’ valuations and participation. The lead application to quantify these relations is takeover auctions: bidders are classified into strategic and financial, and bids are available. I structurally estimate valuations from all bids. The positive difference in premiums between strategic and financial acquirers is driven by the difference in dispersions of valuations (e.g., strategic bidders’ synergies are more dispersed) and the set of auction participants. The difference in average valuations is relatively unimportant. My approach can help explain outcomes of asset sales, even in settings with limited bidder data.  相似文献   
60.
ABSTRACT

We develop a Manipulation Index (ManIx) that captures the potential manipulation intention of dealers during the World Markets/Reuters (WMR) benchmark (London Close) period at 4 pm London time through a unique algorithm and simulation. The application of this model (using a dataset with dealers’ identities) can identify banks that are prone to potential manipulative behavior. The results concerning the identified banks are validated by the regulatory investigations. Implementation of this algorithm allows regulators better direct their limited resources towards more targeted in-depth investigation.  相似文献   
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