SIQA Based on 2D IQA Weighting Strategy

2020 ◽  
pp. 49-67
Author(s):  
Yong Ding ◽  
Guangming Sun
Keyword(s):  
Weighting Strategy

scholarly journals A Similarity Measurement with Entropy-Based Weighting for Clustering Mixed Numerical and Categorical Datasets

Algorithms ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 184
Author(s):  
Xia Que ◽  
Siyuan Jiang ◽  
Jiaoyun Yang ◽  
Ning An
Keyword(s):  
Categorical Data ◽  
Clustering Algorithm ◽  
Numerical Data ◽  
Similarity Measurement ◽  
Amount Of Information ◽  
Automatic Categorization ◽  
Categorical Attributes ◽  
Weighting Strategy

Many mixed datasets with both numerical and categorical attributes have been collected in various fields, including medicine, biology, etc. Designing appropriate similarity measurements plays an important role in clustering these datasets. Many traditional measurements treat various attributes equally when measuring the similarity. However, different attributes may contribute differently as the amount of information they contained could vary a lot. In this paper, we propose a similarity measurement with entropy-based weighting for clustering mixed datasets. The numerical data are first transformed into categorical data by an automatic categorization technique. Then, an entropy-based weighting strategy is applied to denote the different importances of various attributes. We incorporate the proposed measurement into an iterative clustering algorithm, and extensive experiments show that this algorithm outperforms OCIL and K-Prototype methods with 2.13% and 4.28% improvements, respectively, in terms of accuracy on six mixed datasets from UCI.

A novel spatial pooling method for 3D mesh quality assessment based on percentile weighting strategy

2018 ◽  
Vol 74 ◽  
pp. 12-22 ◽  
Author(s):  
Xiang Feng ◽  
Wanggen Wan ◽  
Richard Yi Da Xu ◽  
Stuart Perry ◽  
Pengfei Li ◽  
...  
Keyword(s):  
Quality Assessment ◽  
Mesh Quality ◽  
3D Mesh ◽  
Spatial Pooling ◽  
Weighting Strategy

Volatility Weighting over Time in the Presence of Transaction Costs

2019 ◽  
Keyword(s):  
Transaction Costs ◽  
Empirical Studies ◽  
Risk Control ◽  
Control Technique ◽  
Risk Exposure ◽  
Trading Costs ◽  
Portfolio Risk ◽  
Dynamic Risk ◽  
Weighting Strategy ◽  
Over Time

Numerous empirical studies demonstrate the superiority of dynamic strategies with a volatility-weighting-over-time mechanism. These strategies control the portfolio risk over time by adjusting the risk exposure according to updated volatility forecasts. Yet, to reap all the benefits promised by volatility weighting over time, the composition of the active portfolio must be revised rather frequently. Transaction costs represent a serious obstacle to benefiting from this dynamic risk control technique. In this article, we propose a modified volatility-weighting strategy that allows one to reduce dramatically the amount of trading costs. The empirical evidence shows that the advantages of the modified volatility-weighting strategy persist even in the presence of high transaction costs.

scholarly journals Helmert Variance Component Estimation for Multi-GNSS Relative Positioning

Sensors ◽  
2020 ◽  
Vol 20 (3) ◽  
pp. 669 ◽  
Author(s):  
Mowen Li ◽  
Wenfeng Nie ◽  
Tianhe Xu ◽  
Adria Rovira-Garcia ◽  
Zhenlong Fang ◽  
...  
Keyword(s):  
Variance Component ◽  
Computation Time ◽  
Satellite System ◽  
Unit Weight ◽  
Variance Component Estimation ◽  
Positioning Accuracy ◽  
Gnss Positioning ◽  
Component Estimation ◽  
Weighting Strategy ◽  
Gnss Constellation

The Multi-constellation Global Navigation Satellite System (Multi-GNSS) has become the standard implementation of high accuracy positioning and navigation applications. It is well known that the noise of code and phase measurements depend on GNSS constellation. Then, Helmert variance component estimation (HVCE) is usually used to adjust the contributions of different GNSS constellations by determining their individual variances of unit weight. However, HVCE requires a heavy computation load. In this study, the HVCE posterior weighting was employed to carry out a kinematic relative Multi-GNSS positioning experiment with six short-baselines from day of year (DoY) 171 to 200 in 2019. As a result, the HVCE posterior weighting strategy improved Multi-GNSS positioning accuracy by 20.5%, 15.7% and 13.2% in east-north-up (ENU) components, compared to an elevation-dependent (ED) priori weighting strategy. We observed that the weight proportion of both code and phase observations for each GNSS constellation were consistent during the entire 30 days, which indicates that the weight proportions of both code and phase observations are stable over a long period of time. It was also found that the quality of a phase observation is almost equivalent in each baseline and GNSS constellation, whereas that of a code observation is different. In order to reduce the time consumption of the HVCE method without sacrificing positioning accuracy, the stable variances of unit weights of both phase and code observations obtained over 30 days were averaged and then frozen as a priori information in the positioning experiment. The result demonstrated similar ENU improvements of 20.0%, 14.1% and 11.1% with respect to the ED method but saving 88% of the computation time of the HCVE strategy. Our study concludes with the observations that the frozen variances of unit weight (FVUW) could be applied to the positioning experiment for the next 30 days, that is, from DoY 201 to 230 in 2019, improving the positioning ENU accuracy of the ED method by 18.1%, 13.2% and 10.6%, indicating the effectiveness of the FVUW.

Stochastic Response Surface Method with Enhanced Weighting Strategy

2012 ◽  
Vol 224 ◽  
pp. 272-279
Author(s):  
Gao Rong Sun
Keyword(s):  
Response Surface ◽  
Response Surface Method ◽  
Negative Impact ◽  
Failure Surface ◽  
Stochastic Response ◽  
Weighting Method ◽  
Additional Function ◽  
Stochastic Response Surface Method ◽  
Surface Method ◽  
Weighting Strategy

The weighted stochastic response surface method (WSRSM) has been demonstrated to be effective in improving the accuracy of the estimation of statistical moments and probability of failure (PoF) upon the stochastic response surface method (SRSM). However, it has been noticed that the weighting method in WSRSM may have little and sometimes negative impact on PoF estimation especially in the cases of low PoF. To address this issue, an enhanced weighting strategy is proposed that the weights of sample points are determined based on their importance not only to regression but also to PoF estimation. Specifically, relatively larger weights are assigned to points closer to the failure surface, which significantly accounts for the accuracy of PoF estimation. Comparative studies show that SRSM with the proposed weighting method outperforms WSRSM producing more accurate PoF estimation without incurring additional function evaluations.

scholarly journals Angle-Awareness Based Joint Cooperative Positioning and Warning for Intelligent Transportation Systems

Sensors ◽  
2020 ◽  
Vol 20 (20) ◽  
pp. 5818
Author(s):  
Zhi Dong ◽  
Bobin Yao
Keyword(s):  
Traffic Safety ◽  
Intelligent Transportation Systems ◽  
Estimation Algorithm ◽  
Intelligent Transportation ◽  
Transportation Systems ◽  
Cooperative Positioning ◽  
Traffic Efficiency ◽  
Sequential Task ◽  
Weighting Strategy ◽  
Eigen Decomposition

In future intelligent vehicle-infrastructure cooperation frameworks, accurate self-positioning is an important prerequisite for better driving environment evaluation (e.g., traffic safety and traffic efficiency). We herein describe a joint cooperative positioning and warning (JCPW) system based on angle information. In this system, we first design the sequential task allocation of cooperative positioning (CP) warning and the related frame format of the positioning packet. With the cooperation of RSUs, multiple groups of the two-dimensional angle-of-departure (AOD) are estimated and then transformed into the vehicle’s positions. Considering the system computational efficiency, a novel AOD estimation algorithm based on a truncated signal subspace is proposed, which can avoid the eigen decomposition and exhaustive spectrum searching; and a distance based weighting strategy is also utilized to fuse multiple independent estimations. Numerical simulations prove that the proposed method can be a better alternative to achieve sub-lane level positioning if considering the accuracy and computational complexity.

Sign in / Sign up

Export Citation Format

Share Document