Performance of threshold cointegration tests

In this paper, we examine and compare the performance of ordinary least squares (OLS) and instrumental variables (IVs) based single-equation Engle–Granger, error correction model (ECM), and autoregressive-distributed lag (ADL) threshold cointegration tests. Results are additionally compared with the system-equation OLS–ECM test. Finite sample properties of size and power are examined in simulations. The single-equation ECM test performs well, but has certain limitations to resolve. The system-equation ECM test has good power, but suffers from mild size distortions that lead to over-rejections. Overall, the single-equation OLS–ADL test has the most desirable properties among the OLS-based tests and the IV–ADL test has the most desirable properties among the IV-based tests. The IV-based tests are invariant to nuisance parameters and have a standard normal distribution in each case, while the OLS-based tests are non-standard so that critical values must be simulated in different models.     

Statistical issues in studying the relative importance of body mass index,waist circumference,waist hip ratio and waist stature ratio to predict type 2 diabetes

Systematic and appropriate statistical analysis is needed to examine the relative performance of anthropometrical indices, viz. body mass index (BMI), waist circumference (WC), waist hip ratio (WHR) and waist stature ratio (WSR) for predicting type 2 diabetes. Using information on socio-demographic, anthropometric and biochemical variables from 2148 males, we examined collinearity and non-linearity among the predictors before studying the association between anthropometric indices and type 2 diabetes. The variable involving in collinearity was removed from further analysis, and the relative importance of BMI, WC and WHR was examined by logistic regression analysis. To avoid non-interpretable odds ratios (ORs), cut point theory is used. Optimal cut points are derived and tested for significance. Multivariable fractional polynomial (MFP) algorithm is applied to reconcile non-linearity. As expected, WSR and WC were collinear with WHR and BMI. Since WSR was jointly as well as independently collinear, it was dropped from further analysis. The OR for WHR could not be interpreted meaningfully. Cut point theory was adopted. Deciles emerged as the optimal cut point. MFP recognized non-linearity effects on the outcome. Multicollinearity among the anthropometric indices was examined. Optimal cut points were identified and used to study the relative ORs. On the basis of the results of analysis, MFP is recommended to accommodate non-linearity among the predictors. WHR is relatively more important and significant than WC and BMI.     

A procedure for optimal augmentation of multidimensional designs

The augmentation of an existing multidimensional design is discussed from the point of view of estimability of certain two-factor interactions which are nonestimable from the original design. A general procedure is proposed which achieves this with a minimal number of additional assemblies and which is optimal in a certain sense. The individual steps in this procedure are described in detail and illustrated by an example.     

国际石油价格波动对我国物价水平影响研究

国际石油价格波动会对一国物价水平产生较大的冲击,这种冲击对消费者价格指数和生产者价格指数的影响程度不同,Johansen协整和Granger因果关系检验等是研究此类问题有效的计量经济方法。研究结果显示,国际石油价格与我国两种物价指数之间均存在长期协整关系,但只具有石油价格到物价的单向因果关系,且国际石油价格波动对我国生产者价格水平影响较显著。     

成人高等教育投资与区域经济增长关系的实证研究

文章运用面板单位根检验、面板协整检验和面板误差修正模型等方法对中国东、中、西部地区的成人高等教育投资与区域经济增长的关系进行了比较研究。结果表明,从长期来看,东、中部地区成人高等教育投资与区域经济增长之间具有明显的双向长期因果关系,但是西部地区只存在从成人高等教育投资到区域经济增长的单向因果关系;就短期而言,中、西部地区成人高等教育投资与区域经济增长之间无因果关系,东部地区只存在从区域经济增长到成人高等教育投资的单向因果关系。     

Markov chain Monte Carlo tests for designed experiments

We consider conditional exact tests of factor effects in designed experiments for discrete response variables. Similarly to the analysis of contingency tables, a Markov chain Monte Carlo method can be used for performing exact tests, when large-sample approximations are poor and the enumeration of the conditional sample space is infeasible. For designed experiments with a single observation for each run, we formulate log-linear or logistic models and consider a connected Markov chain over an appropriate sample space. In particular, we investigate fractional factorial designs with 2^p-q$2^{p-q}$ runs, noting correspondences to the models for 2^p-q$2^{p-q}$ contingency tables.     

诉讼量与经济增长的协整关系研究

诉讼是人民或检察官请求司法官本着司法权裁判的行为。通过利用1978—2011年的人民法院审理一审案件数与国民生产总值样本数据,对诉讼量与经济增长的协整关系进行实证研究。结果表明:在长期内诉讼量与经济增长的关系是稳定均衡的;在短期内,经济增长的变动受到自身和诉讼量变动因素的影响,其影响作用随着时间的推移而逐渐衰减,且诉讼量和经济增长之间的均衡关系对当期非均衡误差调整的自身修正能力较弱。从长期看,二者之间构成了长期稳定的均衡关系。     

消费信贷对中国居民消费影响效应的实证研究

基于2007年1月至2012年10月的样本数据,采用协整检验和脉冲响应分析,从长期和短期两方面实证研究了消费信贷对中国居民消费的影响效应.研究表明,长期内消费信贷不会对居民消费产生显著影响,即增加消费信贷并不会改变人们的边际消费倾向;短期内消费信贷不仅刺激了消费需求,而且扩大消费信贷会对国内需求产生显著的正向影响.     

Finite sample performance of frequency- and time-domain tests for seasonal fractional integration

Testing the order of integration of economic and financial time series has become a conventional procedure prior to any modelling exercise. In this paper, we investigate and compare the finite sample properties of the frequency-domain tests proposed by Robinson [Efficient tests of nonstationary hypotheses, J. Amer. Statist. Assoc. 89(428) (1994), pp. 1420–1437] and the time-domain procedure proposed by Hassler, Rodrigues, and Rubia [Testing for general fractional integration in the time domain, Econometric Theory 25 (2009), pp. 1793–1828] when applied to seasonal data. The results presented are of empirical relevance as they provide some guidance regarding the finite sample properties of these tests.     

融资融券背景下证券配对交易策略研究——基于协整和距离的两阶段方法

国内融资融券政策的正式启动,为证券配对交易实施提供了必要的市场环境,使其成为一种新兴有效的投资手段。基于协整配对法和距离配对法,本文构建了一种新的两阶段配对交易策略。在股票配对选择方面,首先采用协整分析选出具有相似股价走势的候选股票对;其次,采用欧式距离计算各候选配对股票距离,以距离最小为依据选择最佳股票配对,以避免同一股票同时被买入和卖空的风险。在资金分配方面,考虑当前融资融券交易制度背景,求解资金有限约束下的最优资金分配方案,以保证模型设计更为接近实际交易情况。以上证50指数成分股为实证对象,实证研究结果表明不同费率情景下,构建的新两阶段方法均能获得超额收益,且其效果明显优于仅考虑协整关系的配对交易策略;同时,敏感性分析验证了新方法的稳定性。