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1.
In recent years there has been a growing interest in exploiting potential forecast gains from the non‐linear structure of self‐exciting threshold autoregressive (SETAR) models. Statistical tests have been proposed in the literature to help analysts check for the presence of SETAR‐type non‐linearities in an observed time series. It is important to study the power and robustness properties of these tests since erroneous test results might lead to misspecified prediction problems. In this paper we investigate the robustness properties of several commonly used non‐linearity tests. Both the robustness with respect to outlying observations and the robustness with respect to model specification are considered. The power comparison of these testing procedures is carried out using Monte Carlo simulation. The results indicate that all of the existing tests are not robust to outliers and model misspecification. Finally, an empirical application applies the statistical tests to stock market returns of the four little dragons (Hong Kong, South Korea, Singapore and Taiwan) in East Asia. The non‐linearity tests fail to provide consistent conclusions most of the time. The results in this article stress the need for a more robust test for SETAR‐type non‐linearity in time series analysis and forecasting. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
2.
理性看待特许经营 总被引:1,自引:0,他引:1
李满志 《浙江万里学院学报》2002,15(3):21-24
目前,国内许多企业为了在较短的时间内迅速扩大规模,纷纷采取特许经营模式,有些已经取得了较大的进展,但其中也不乏盲目跟刚才是,文章从国内特许经营存在的问题入手,指出了特许经营中的陷阱及对策。 相似文献
3.
4.
CsLiB6O10晶体光参量振荡器的线宽分析 总被引:1,自引:1,他引:0
采用355nm脉冲激光作为泵浦源,对影响CsLiB_6O_(10)晶体光参量振荡器的信号光线宽的各种物理机制进行了数值模拟计算和分析.结果表明,泵浦光的发散角和偏轴方向对信号光线宽的影响较大。 相似文献
5.
对 11株酵母菌进行了渗透压、乙酸、冷冻、乙醇耐性实验及海藻糖积累的比较。实验表明 ,渗透压耐性和乙酸耐性较好的菌株 ,其积累海藻糖的能力较强 ;而抗冷冻和乙醇耐性与海藻糖的积累能力无明显的相关性。 相似文献
6.
雷曼 《武汉科技大学学报(自然科学版)》1994,(4)
作者提出对IBMPC系列微机上DEBUG实用程序的一种改进方法,即通过修改单步中断和断点中断的处理程序,使之能跟踪“反跟踪软件”,这对软件解密和病毒分析无疑是有用的。 相似文献
7.
Different from traditional tax audit, supervision with self-audit is a combination of audit by the taxpayer himself and audit
by the tax authority. This paper mainly studies a taxpayer’s optimal policy of tax evasion under supervision with self-audit
and its related properties, in order to deduce some effective suggestions and theoretical bases to restrain tax evasion. Assuming
that only a certain proportion of evaded tax can be discovered when the audit is executed, the authors first formulate a static
model with self-audit. This model is divided into two stages. At the first stage, taxpayers declare their taxes, then the
tax authority chooses audit objects, based on a known probability, and announces the result; if the taxpayer is chosen, he
will enter the second stage, during which he has a chance to pay the evaded tax and the corresponding late fees and then is
audited by the tax authority. The authors show the existence and uniqueness of the optimal amount of tax evasion at the first
stage and the optimal proportion to self-expose at the second stage. The authors also discuss the related properties of the
interior solution, and do elasticity analyses on some parameters. Besides, the authors extend the static model into the corresponding
two-period model, and study the existence and uniqueness of the solution of the extended model. Finally, under the assumption
that tax evasion can only be discovered with a certain probability when the audit is executed, the authors formulate another
static model with self-audit and investigate its properties.
This research is partially supported by the National Natural Science Foundation of China under Grant Nos. 60674082, 70221001,
and 70731003. 相似文献
8.
本文通过对塑料瓶盖压缩性能检测证明,每一种塑料瓶盖的压缩性能和压缩曲线都具有特征性,塑料瓶盖的压缩性能和压缩曲线可以作为检测塑料瓶盖真伪的重要依据之一. 相似文献
9.
Summary By comparing steroid sulphatase levels per se, and also ratios to -galactosidase, in 6 sets of mice — normal females, entire and castrated males both with and without exogenous testosterone administration — we obtained support for the contention that induction of this enzyme is in part controlled by male hormones. 相似文献
10.
俞曼 《徐州师范大学学报(自然科学版)》1998,(4)
设H为Hilbert空间,A为H上的有界线性算子,简记为A∈B(H).A的值域R(A)为闭时,则记为A∈BC(H).我们熟知对任意A∈BC(H),存在唯一有界线性算子A+∈B(H),使得:1)AA+=PR(A),2)A+A=PR(A*),3)N(A+... 相似文献