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Aspect Term Extraction (ATE), which aims to extract aspect terms from review sentences, is an important subtask of sentiment analysis. Existing studies have proposed many sequence taggers, which have achieved impressive progress. However, previous work ignores the errors in aspect terms extracted by sequence taggers. This paper points out that there are aspect number error and aspect boundary error in the extracted aspect terms, which have a severe negative impact on the performance of the model on ATE task. We design post-processing method with aspect term error correction, which contain aspect number determining module and aspect boundary modifying module, to address the errors. To solve the inconsistency between the number of extracted aspect terms and the number of ground-truth aspect terms, we use the aspect number determining module to control the number of extracted aspect terms to match the number of ground-truth aspect terms. For the problem that the boundary of the extracted aspect term is not completely matched with the boundary of the ground-truth aspect term, we utilize the aspect boundary modifying module to correct the boundary of the extracted aspect term to make it the same as the boundary of the ground-truth aspect term. Experiments on four SemEval datasets show that the post-processing method can address the errors in extracted aspect terms, and our model outperforms other SOTA models. Our post-processing method can be coupled with various sequence taggers to boost their performance and have well transferability.

In this paper functions f:D→R satisfying the inequality f(x+y2)≤12f(x)+12f(y)+φ(x-y2)(x,y∈D) are studied, where D is a nonempty convex subset of a real linear space X and φ:{12(x-y):x,y∈D}→R is a so-called error function. In this situation f is said to be φ-Jensen convex. The main results show that for all φ-Jensen convex function f:D→R, for all rational λ∈[0,1]and x,y∈D, the following inequality holdsf(λx+(1-λ)y)≤λf(x)+(1-λ)f(y)+∑k=0∞12kφ((2kλ,Z)·(x-y)). The infinite series on the right hand side is always convergent, moreover, for all rational λ∈[0,1], it can be evaluated as a finite sum.

With the rapid development of inertial navigation technology, the proportion of inertial navigation technology in navigation and positioning is getting higher and higher. The measurement accuracy requirements of inertial components are getting higher and higher. Based on the mature linear calibration method, this article calibrates the quadratic error of the accelerometer component in the inertial component and compensates the error term. In theory, the least squares estimation is used to solve the quadratic parameter. After considering the quadratic term, the measurement accuracy of the gravity sensor has been improved, and the laboratory gravimeter has been used for marine experiments. The experimental results show that the positioning deviation considering the quadratic error term is smaller than the positioning deviation considering only the first error term.

This book provides a solution to the ecological inference problem, which has plagued users of statistical methods for over seventy-five years: How can researchers reliably infer individual-level behavior from aggregate (ecological) data? In political science, this question arises when individual-level surveys are unavailable (for instance, local or comparative electoral politics), unreliable (racial politics), insufficient (political geography), or infeasible (political history). This ecological inference problem also confronts researchers in numerous areas of major significance in public policy, and other academic disciplines, ranging from epidemiology and marketing to sociology and quantitative history. Although many have attempted to make such cross-level inferences, scholars agree that all existing methods yield very inaccurate conclusions about the world. In this volume, Gary King lays out a unique--and reliable--solution to this venerable problem. King begins with a qualitative overview, readable even by those without a statistical background. He then unifies the apparently diverse findings in the methodological literature, so that only one aggregation problem remains to be solved. He then presents his solution, as well as empirical evaluations of the solution that include over 16,000 comparisons of his estimates from real aggregate data to the known individual-level answer. The method works in practice. King's solution to the ecological inference problem will enable empirical researchers to investigate substantive questions that have heretofore proved unanswerable, and move forward fields of inquiry in which progress has been stifled by this problem.

Higher-order error terms (HOET) occur inevitably during the geometric error modelling and compensation of a machine tool using both screw theory and multi-body system (MBS) theory. Though the HOET has little influence on machining accuracy, it will make analysis and compensation of geometric errors complicated and tedious. Especially, it is necessary to eliminate the higher-order error terms artificially when deriving the analytical expressions for geometric error compensation. Hence, a novel geometric error modelling and compensation algorithm without the interference of HOET is proposed in this paper. Taking a three-axis CNC machine tool as an example. A new summation operation rule for geometric error modelling was defined according to the homogeneous transformation matrix (HTM) method, which has no multiplication between error matrices. And the analytical expressions of motion-axis commands for error compensation could be calculated directly according to the new modelling algorithm without manual deletion of HOET. Active elimination of HOET can simplify the process of geometric error modelling and compensation and can significantly improve efficiency. The results show that the acquisition efficiency of symbolic compensation expressions can be improved by at least 70% compared to the traditional actual inverse kinematics. Moreover, the HOET are automatically eliminated and has a small influence on the compensation accuracy. Finally, a cutting experiment was conducted and analyzed to verify the high efficiency and effectiveness of the proposed method.

This paper uses an improved DEVA model and stochastic frontier gravity method to combine natural and inefficient influencing factors to measure the optimal trade potential using cross-border e-commerce trade volume so that the stochastic disturbance term obeys a semi-normal truncated distribution. The optimal export value in cross-border e-commerce is calculated based on the trade inefficiency term to derive the factors affecting agricultural trade. The results show that the development scale of cross-border e-commerce trade in agricultural products continues to expand, and the export trade volume in western Anhui Province increased by 940,000 yuan in 2018, and the trade efficiency value fluctuates between 0.11 and 0.20. Strengthening control and improving the cross-border logistics system can help promote the high-quality development of cross-border trade in agricultural products and promote the construction of rural revitalization.

Sensitivity analysis of the key error terms is the prerequisite to improve the accuracy and reliability of machine tools. The purpose of this article is to identify and compensate key error terms. Based on the IMD-H (Improve Modify D-H) parameter method, the error model of machine tools is established. According to the randomness of each error item of machine tools under actual working conditions, a novel concept of “Risk Equivalent Factor” is proposed to reflect the influence of the mean and variance of error items on the total error size and stability of machine tools, so as to identify the key error items. In addition, the coupling characteristics of multiple error terms are analyzed, and the influence of the random characteristics of error terms on the actual machining path is studied. The sensitivity analysis method proposed can more accurately identify the main error items that cause machining errors, which can be used for machine tool error compensation operations. Finally, the effectiveness of the dynamic sensitivity analysis method proposed was proved by the machining error compensation experiment.

Understanding common errors that students of a foreign language make and their causes can enhance our ability to adjust teaching methodologies. This paper aimed to analyze errors that Albanian students of German language and literature make when writing texts in German as a foreign language. This qualitative and quantitative analysis set out to identify and classify errors and find the causes of errors. The study is based on 100 students of German at the B1 level, including participants from language schools and first-year students from the German Department at the University of Prishtina “Hasan Prishtina”. Students were required to submit written texts for analysis. The analysis of these texts was used to address the following research question: What are the typical and recurrent errors made by learners of German as a foreign language (GFL) and what are their causes? The analysis of written texts showed that errors occur at all linguistic levels, with grammatical errors being the most common, followed by orthography and punctuation and syntax. Most errors arose from interference between the native Albanian and the foreign language English, followed by competence and overgeneralization.

Denote by Δ1(x;φ) the error term in the classical Rankin–Selberg problem. Denote by ζ(s) the Riemann zeta-function. We establish an upper bound for this integral ∫0TΔ1(t;φ)ζ12+it2dt. In addition, when 2≤k≤4 is a fixed integer, we will derive an asymptotic formula for the integral ∫1TΔ1k(t;φ)ζ12+it2dt. The results rely on the power moments of Δ1(t;φ) and E(t), the classical error term in the asymptotic formula for the mean square of ζ12+it.

Transverse navigation has been proposed to help inertial navigation systems (INSs) fill the gap of polar navigation ability. However, as the transverse system does not have the ability of navigate globally, a complicated switch between the transverse and the traditional algorithms is necessary when the system moves across the polar circles. To maintain the inner continuity and consistency of the core algorithm, a hybrid transverse polar navigation is proposed in this research based on a combination of Earth-fixed-frame mechanization and transverse-frame outputs. Furthermore, a thorough analysis of kinematic error characteristics, proper damping technology and corresponding long-term contributions of main error sources is conducted for the high-precision INSs. According to the analytical expressions of the long-term navigation errors in polar areas, the 24-h period symmetrical oscillation with a slowly divergent amplitude dominates the transverse horizontal position errors, and the first-order drift dominates the transverse azimuth error, which results from the g 0 gyro drift coefficients that occur in corresponding directions. Simulations are conducted to validate the theoretical analysis and the deduced analytical expressions. The results show that the proposed hybrid transverse navigation can ensure the same accuracy and oscillation characteristics in polar areas as the traditional algorithm in low and mid latitude regions.