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31.
This paper analyzes the role of initialization when testing for a unit root in panel data, an issue that has received surprisingly little attention in the literature. In fact, most studies assume that the initial value is either zero or bounded. As a response to this, the current paper considers a model in which the initialization is in the past, which is shown to have several distinctive features that makes it attractive, even in comparison to the common time series practice of making the initial value a draw from its unconditional distribution under the stationary alternative. The results have implications not only for theory, but also for applied work. In particular, and in contrast to the time series case, in panels the effect of the initialization need not be negative but can actually lead to improved test performance.  相似文献   
32.
In this paper, we propose two new estimators of treatment effects in regression discontinuity designs. These estimators can aid understanding of the existing estimators such as the local polynomial estimator and the partially linear estimator. The first estimator is the partially polynomial estimator which extends the partially linear estimator by further incorporating derivative differences of the conditional mean of the outcome on the two sides of the discontinuity point. This estimator is related to the local polynomial estimator by a relocalization effect. Unlike the partially linear estimator, this estimator can achieve the optimal rate of convergence even under broader regularity conditions. The second estimator is an instrumental variable estimator in the fuzzy design. This estimator will reduce to the local polynomial estimator if higher order endogeneities are neglected. We study the asymptotic properties of these two estimators and conduct simulation studies to confirm the theoretical analysis.  相似文献   
33.
In this article, we provide a semiparametric approach to the joint measurement of technical and allocative inefficiency in a way that the internal consistency of the specification of allocative errors in the objective function (e.g., cost function) and the derivative equations (e.g., share or input demand functions) is assured. We start from the Cobb–Douglas production and shadow cost system. We show that the shadow cost system has a closed-form likelihood function contrary to what was previously thought. In turn, we use the method of local maximum likelihood applied to a system of equations to obtain firm-specific parameter estimates (which reveal heterogeneity in production) as well as measures of technical and allocative inefficiency and its cost. We illustrate its practical application using data on U.S. electric utilities.  相似文献   
34.
Very little is known about the local power of second generation panel unit root tests that are robust to cross-section dependence. This article derives the local asymptotic power functions of the cross-section argumented Dickey–Fuller Cross-section Augmented Dickey-Fuller (CADF) and CIPS tests of Pesaran (2007), which are among the most popular tests around.  相似文献   
35.
This article considers a nonparametric additive seemingly unrelated regression model with autoregressive errors, and develops estimation and inference procedures for this model. Our proposed method first estimates the unknown functions by combining polynomial spline series approximations with least squares, and then uses the fitted residuals together with the smoothly clipped absolute deviation (SCAD) penalty to identify the error structure and estimate the unknown autoregressive coefficients. Based on the polynomial spline series estimator and the fitted error structure, a two-stage local polynomial improved estimator for the unknown functions of the mean is further developed. Our procedure applies a prewhitening transformation of the dependent variable, and also takes into account the contemporaneous correlations across equations. We show that the resulting estimator possesses an oracle property, and is asymptotically more efficient than estimators that neglect the autocorrelation and/or contemporaneous correlations of errors. We investigate the small sample properties of the proposed procedure in a simulation study.  相似文献   
36.
基于LW估计的中国证券市场长记忆性实证研究   总被引:1,自引:0,他引:1  
针对国内研究证券市场长记忆性主要采用的是时域方法,文章采用基于频域的半参数Local Whittle估计方法研究了中国证券市场的长记忆特性,并且和对数周期图回归(GPH)方法进行了比较。结果表明,LW方法具有不受时间频率的影响,能够有效消除时间序列中短期记忆和周期性对估计结果的影响等优点,明显优于GPH方法。实证结果表明,中国证券市场存在明显的长记忆性,并且长记忆行为在重大突发事件发生期间更加明显。文章还从长记忆的角度探讨了“政策市”的存在性和相关特点。  相似文献   
37.
This paper examines the construction of Bai ethnicity and Bai identity on the tourist market in Dali, Dali Bai Autonomous Prefecture, Yunnan, China. Focusing on how the social landscape of Dali has changed in response to the development of tourism, this paper explores how Bai ethnicity is advocated as a product loaded with potential economic values. The author discovers that ‘commerce of authenticity’ (T. Oakes, Tourism and modernity in China. London, Routledge, 1998 Oakes, T. 1998. Tourism and modernity in China, London: Routledge.  [Google Scholar]), and different forms of ethnicity and artefacts promoted in the tourist market have not drowned out the sense of being ethnically Bai. Instead, the tourist industry has become a daily reminder of ethnicity to both insiders and outsiders by making people more self-conscious and reflexive about the ‘cultural stuff’ that they may have previously taken for granted, or may have left unattended. This paper demonstrates how locals actively appropriate state-defined categories and reshape them into the repertoire they desire.  相似文献   
38.
With sector constraints and higher education economic imperatives increasingly impacting the provision of social work field education, university programs lack an understanding of the factors that enable or prohibit field educators’ capacity to provide placements. Despite the significance of field education in the curriculum, it remains unclear what the experiences and motivations of field educators are to provide universities with student placements. This research addresses this gap through surveying 101 field educators that attended statewide Victorian field education training. Results indicated that although field educators recognised the benefits of supervising students, workload relief, additional training, and further student placement preparation by the university were emphasised as the primary factors that would enable them to respond positively to placement requests. Payments for placements did not necessarily ameliorate these issues nor guarantee the provision of more placements. The implications of these findings for universities and the field are discussed.  相似文献   
39.
《Long Range Planning》2019,52(5):101825
Research on problemistic search has assumed negative attainment discrepancy to be the trigger of both local and distant search. Extending this research, we present and compare two additional triggers: (1) relative attainment discrepancy, which reflects how much a firm's attainment discrepancy deviates from its past negative attainment discrepancies; and (2) persistent attainment discrepancy, which reflects how often the firm experiences below-aspirations performance. Our triggers for distant search model a behavioral explanation for the timing and relatedness of acquisitions. We find support for baseline arguments of problemistic search whereby firms increase both industry- and skill-related acquisitions when they perform below aspirations. When they persistently perform below aspirations, however, this likelihood is reduced and firms engage in acquisitions that are more unrelated, thereby providing support for the notion of expanding search boundaries from local to distant search. Of the two triggers of distant search proposed, relative attainment discrepancy does not induce firms to expand search boundaries. Our results indicate that persistent attainment discrepancy is a key construct to consider when studying the expansion of search boundaries.  相似文献   
40.
“985高校”专利竞争力研究   总被引:1,自引:0,他引:1  
"985高校"是我国专利产出大户,其专利竞争力对整个国家的竞争力都具有重要影响。高校专利竞争力就是高校利用专利这种特殊资源持续获取竞争优势的能力,主要体现为现实竞争力和潜在竞争力两个维度。现实竞争力包括专利数量和质量,潜在竞争力包括研发潜力和专利增长。基于此,设置九个三级指标,构建线性加权评价模型,对"985高校"专利竞争力进行评价,结果发现"985高校"专利竞争力差异较大,专利质量整体薄弱;最后,针对评价结果提出专利竞争力提升对策,以期各高校参考。  相似文献   
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