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161.
Hiroko Kato Solvang Masanobu Taniguchi Tomohiro Nakatani Shigeaki Amano 《Statistical Methodology》2008,5(3):187-208
Fundamental frequency (F0) patterns, which indicate the vibration frequency of vocal cords, reflect the developmental changes in infant spoken language. In previous studies of developmental psychology, however, F0 patterns were manually classified into subjectively specified categories. Furthermore, since F0 has sequential missing and indicates a mean nonstationarity, classification that employs subsequent partition and conventional discriminant analysis based on stationary and local stationary processes is considered inadequate. Consequently, we propose a classification method based on discriminant analysis of time series data with mean nonstationarity and sequential missing, and a measurement technique for investigating the configuration similarities for classification. Using our proposed procedures, we analyse a longitudinal database of recorded conversations between infants and parents over a five-year period. Various F0 patterns were automatically classified into appropriate pattern groups, and the classification similarities calculated. These similarities gradually decreased with infant’s monthly age until a large change occurred around 20 months. The results suggest that our proposed methods are useful for analysing large-scale data and can contribute to studies of infant spoken language acquisition. 相似文献
162.
运用相对论的密度泛函离散变分法(DV-Xa)研究了SrWO4晶体中F型色心的电子结构.计算结果表明,F和F+心在禁带中引入了新的施主能级;从施主能级到导带底的电子跃迁能分别是1.858,2.14 eV,这分别与669,581 nm的吸收带相对应.由此说明SrWO4晶体中669,581 nm吸收带起源于晶体中的F和F+心. 相似文献
163.
In the context of the public policy debate, we explore firm-level characteristics that influence firms’ preferences related to alternatives to harmonize standards within the Transatlantic Trade and Investment Partnership (TTIP). The options are the implementation of common standards, developed internationally or bilaterally, and mutual recognition. The empirical analysis is based on data from the German Standardization Panel. We identify three dimensions that determine firms’ preferences regarding the various harmonization solutions: (1) company-specific factors, such as size, industry and motives to apply standards, (2) the competitive environment, i.e. the position vis-à-vis other market participants, and (3) the technological environment, i.e. the dynamics of the market the company operates in. 相似文献
164.
165.
Alexandre M. Berred 《Statistics》2013,47(2):93-109
Let {X n:n ≥ 1} be an i.i.d. sequence of random variables with a continuous distribution function F. Under the assumption that the upper tail of Fis regularly varying with exponent 1/α, α > 0, we study the asymptotic properties of an estimator of α based on k-record values. 相似文献
166.
《随机性模型》2013,29(2):281-300
The branching processes with state-dependent immigration are considered as alternating regenerative processes. The main purpose is to demonstrate some new “regenerative” methods. Critical Bellman–Harris branching processes with state-dependent immigration are investigated and new limit theorems are obtained in the case of an infinite offspring variance and possibly infinite mean of the immigrants. 相似文献
167.
Christian Lavergne 《Statistics》2013,47(1-2):1-13
This paper concerns a method of estimation of variance components in a random effect linear model. It is mainly a resampling method and relies on the Jackknife principle. The derived estimators are presented as least squares estimators in an appropriate linear model, and one of them appears as a MINQUE (Minimum Norm Quadratic Unbiased Estimation) estimator. Our resampling method is illustrated by an example given by C. R. Rao [7] and some optimal properties of our estimator are derived for this example. In the last part, this method is used to derive an estimation of variance components in a random effect linear model when one of the components is assumed to be known. 相似文献
168.
设计了一种基于HT66F70A型单片机的汽车落水应急救护系统,系统由供电电路、汽车落水检测电路、HT66F70A单片机电路、逃生救护报警电路4部分构成.本系统利用液位变送器测取液体压力并将其转换成电压信号输出,电压信号经过HT66F70A内部的12位A/D转换器转换成数字信号,单片机根据数字信号来控制逃生救护报警电路.该系统能够在汽车落水时启动语音报警、点亮呼救灯、显示汽车在水中的下沉深度,开启呼吸通道为乘客提供呼吸环境,并打开车窗为乘客开辟逃生通道.通过仿真测试,表明本系统具有反应灵敏、测试精度高、体积小巧、价格低廉的优点,故本系统具有很好的推广应用价值. 相似文献
169.
We incorporate appropriation activities (social conflict) into canonical models of trade and study how economic shocks and policies affect the intensity of conflict. We show that not all shocks that could make society richer reduce conflict: positive shocks to labor‐intensive industries diminish conflict, while positive shocks to capital‐intensive industries increase it. The key requirement is that conflict activities be more labor intensive than the economy as this determines how shocks affect the returns and costs of conflict. Our theory is consistent with several observed patterns of conflict and implies that empirical work should take into account the relative factor intensities of the productive and conflict sectors in each country. Incorporating appropriation into a canonic general equilibrium model affects what policies may be deemed desirable: in order to reduce conflict and generate Pareto‐improvements policy must be distortionary, while reforms that appear efficiency‐enhancing under the unrealistic assumption of perfect property rights may backfire. This offers one explanation for why reforms based on traditional models without appropriation may be delayed and become unpopular when implemented, and why societies may sympathize with seemingly inefficient redistribution. 相似文献
170.
We study the effects of economic and political integration by presenting a model in which firms compete with each other in both an economic market—where they produce a good and compete for market share—and in a political (rent seeking) market—where they compete for transfers from the government. Growth is driven by firms’ cost‐reducing innovation activity and economic and political integration affect firms’ incentive to innovate differently. In this setting, economic and political integration can be seen as complementary. Economic integration, when not accompanied by political integration, can lead to less innovation and slower growth as firms respond to increased competition in the economic market by focusing more on rent‐seeking activity. When economic integration is accompanied by political integration, innovation and growth will be stronger and welfare higher. 相似文献