Some new classes of multivariate survival distribution functions

The concept of the univariate mean remaining life (m.r.l.) function is generalized to the multivariate case. The multivariate mean remaining life (m.m.r.l.) function is utilized to introduce four new classes of multivariate survival distribution functions (s.d.f.'s). Each of these classes is a new generalization of the univariate decreasing mean remaining life (DMRL) class of s.d.f.'s. The duals of these classes are introduced. Some properties, physical interpretation, and relationships among these classes are investigated. Also for each case, the class of s.d.f.'s common in a class and its dual is characterized.     

GM(1,N)模型的病态矩阵的产生及主成分估计改进法

本文在文献[1]的基础上给出了更为一般的探讨,并且用主成分估计法改进了灰色系统模型。     

函数的Tchebycheff—Fourier级数的(N,P)平均逼近

讨论了算子（N，P）的最佳逼近阶以及达到此逼近阶的一个充分条件。得到了f∈Lipα及f’∈Lipα时逼近误差的上界。     

不同不育系所配杂交水稻组合在单、双株寄栽条件下的秧苗素质分析

通过对不同不育系所配杂交水稻组合在单、双株寄裁条件下的秧苗素质研究，结果表明：Ⅱ-32A所配组合的总根数、白根数、白根率和分蘖性能等指标均较优，特别是白根率高，根系活力和分案能力强，但繁茂性稍差。冈46A所配组合其突出特点是叶面积和苗高占优势，繁茂性好，秧田各时期的于物质积累能力较强，但根系活力稍差，白根率较低。二汕A所配组合的特点是在发根力和根系活力上稍占优势，白报率较高。D汕A所配组合无突出特点。寄款方式对秧苗素质影响很大，主要表现在前期和后期的差异大。前期双株秧稍占优势，但在后期刊单株放的优势很明显。因此，在土壤肥沃，水源充足的地方，为培育壮秧，增加秧龄弹性，应提倡单株寄栽。     

Estimation of a standard measuring error by repeated measurements and sortings

A sorting-and-measuring machine (SMM) measures and sorts (classifies) on-line produced items into several groups according to their size. The measuring devices of the SMM perceive the actual item size with a random error ε and classify the item as being smaller than b iff z+ε<b. Here ε is a normal zero-mean r.v. with unknown standard deviation σ which is the main parameter characterizing the precision and technical condition of an SMM. The paper gives the following method of estimating σ. N₀ items are measured and N₁ of them are recognized by the SMM as belonging to the group a<z≤b. These N₁ items are sorted again and N₂ of them return to this group, these are sorted again, and so on. The estimation of σ is based on the statistics N_m/N_n. Moments of the ratio statistics N_m/N_n and their distributional properties are investigated. It turns out that the expected value of N_m/N_n depends almost linearly on σ which allows us to construct ‘almost’ unbiased estimators of type $\text{σ}\text{?}{}_{\mathrm{mn}}\text{=A}\textcolor{red}{}\text{N}{}_{\mathrm{m}}\text{/N}{}_{\mathrm{n}}\text{+B}$ with good propert including robustness with respect to the distribution of item size. Convex combinations of $\text{σ}\text{?}{}_{\mathrm{mn}}$ statistics are considered to obtain an estimator with minimal variance.     

试论语言模因的局限 — —以“舌尖上的X”的发展演变为例

摘要：通过对以“舌尖上的X”为标题的新闻的整理归纳,分析“舌尖上的X”在传播中产生的语义和句法构成的演变,发现其在 模仿复制传播过程中的局限性,揭示语言模因传播中造成的词义固化、语义不明等问题,同时还注意到了指称名词成为模因之 后造成的以偏概全的标签化问题。     

China’s first priority in post-war state building: A wealthy state,or a strong army?

This analysis examined causal links in China’s defence–growth nexus in 1960–2016. The results show that better growth significantly reduces military-civilian ratio and propels military reforms. The unidirectional threshold causality from growth to defence shows that the military impact on a positive change in China’s growth is little in the long term. Conversely, the growth impact of a positive change in defence has accelerated after it reaches the threshold year in 1987. This finding explains why Chinese economy stagnated when defence was prioritised and why China has risen dramatically in the Far East after three decades of fast economic growth.     

Decentralization and growth: Do informal institutions and rule of law matter?

We develop a model of the interactions among decentralization, informal institutions and the rule of law. The model sheds light on the ambiguous empirical results reported in the literature regarding the growth effects of the policy of devolving fiscal responsibility to local governments. We find that the distribution of civicness within a country determines the magnitude of the effects of decentralization on its regional convergence, as well as whether decentralization fosters or dampens the country’s national growth. We perform a series of simulated “reforms” using Monte Carlo methods parameterized using OECD countries data set. We then test our findings using a panel data set of 23 OECD countries covering the period 1975–2010. We find that the short and the long run growth effect of decentralization policy depends on the size of the policy reform and can range from extremely negative to positive depending on the rule of law, the level of social capital and its regional dispersion, in line with the model predictions.     

Additive time-dependent hazard model with doubly truncated data

For doubly truncated data, i.e. the variables of interest are only observable if they lie in a certain random interval, an additive hazard model with time-dependent regression coefficients is investigated. Consistency and asymptotic normality are proven under mild assumptions. A simulation study investigates the finite sample properties and the influence of the truncation distribution on the estimation error. Finally, the method is applied to a doubly truncated data set of German companies, where the age at insolvency is of interest.     

Pseudo MLE for semiparametric transformation model with doubly truncated data

In this article, we consider the efficient estimation of the semiparametric transformation model with doubly truncated data. We propose a two-step approach for obtaining the pseudo maximum likelihood estimators (PMLE) of regression parameters. In the first step, the truncation time distribution is estimated by the nonparametric maximum likelihood estimator (Shen, 2010a) when the distribution function $K$ of the truncation time is unspecified or by the conditional maximum likelihood estimator (Bilker and Wang, 1996) when $K$ is parameterized. In the second step, using the pseudo complete-data likelihood function with the estimated distribution of truncation time, we propose expectation–maximization algorithms for obtaining the PMLE. We establish the consistency of the PMLE. The simulation study indicates that the PMLE performs well in finite samples. The proposed method is illustrated using an AIDS data set.