Extracting Summary Statistics of Rapid Numerical Sequences

We examine the ability of observers to extract summary statistics (such as the mean and the relative-variance) from rapid numerical sequences of two digit numbers presented at a rate of 4/s. In four experiments (total N = 100), we find that the participants show a remarkable ability to extract such summary statistics and that their precision in the estimation of the sequence-mean improves with the sequence-length (subject to individual differences). Using model selection for individual participants we find that, when only the sequence-average is estimated, most participants rely on a holistic process of frequency based estimation with a minority who rely on a (rule-based and capacity limited) mid-range strategy. When both the sequence-average and the relative variance are estimated, about half of the participants rely on these two strategies. Importantly, the holistic strategy appears more efficient in terms of its precision. We discuss implications for the domains of two pathways numerical processing and decision-making.

Diagnosing the Level of Job Performance for a Sample of the Directorates of the Iraqi Ministry of Interior: An Exploratory Study

The research aims to diagnose the level of job performance in the directorates of the Iraqi Ministry of Interior ,The current research adopted the descriptive analytical method ,Starting from a problem and questions that emerged from a main question (were the leaders of the surveyed directorates able to improve job performance, Its data were collected from (101) respondents who represent the research sample in an intentional, quota, way, after being completely enumerated Represented by managers (department managers, division managers), the questionnaire was adopted as a tool for collecting research data, which included (40) paragraphs by which the variables investigated in (the Directorate of Relations and media , the Directorate of Planning and Follow-up, the Directorate of Systems and Informatics, the Directorate of Identities and Leaves), were measured, Personal interviews and field observations were used, and the research adopted a program (SMART PLS V.3.3, Spss V.26) with the adoption of descriptive statistics methods (normal distribution test, confirmatory and exploratory factor analysis, structural modeling, arithmetic mean, percentages, standard deviation, and relative importance, The coefficient of relative variance, the Pearson correlation coefficient, the coefficient of simple and multiple regression), The research concluded with the most prominent result represented in the direction of the leaders of the surveyed directorates towards contextual performance, which indicates that their employees carry out tasks that go beyond their official roles and their quest to volunteer in additional activities and help others, as well as the leaders’ interest in the job performance of their employees, so I proceeded to improve it, as well as directly improving the performance of the task.

TERRAIN-ADAPTIVE GROUND FILTERING OF AIRBORNE LIDAR DATA BASED ON SALIENCY-AWARE THIN PLATE SPLINE

Ground filtering separates the ground and non-ground points from point clouds, which is the essential process for DEM generation, semantic segmentation, model reconstruction and so forth. Considering the topologically complex terrain environments, the segmentation results are prone to be disturbed dealing with steep slopes, buildings, bridges, cliffs, etc. from Airborne LiDAR point clouds. In this paper, a saliency-aware Thin-Plate-Spline (SATPS) interpolation method is proposed including two steps: saliency division and adaptive regularized TPS interpolation with relative variance coefficient. Firstly, the point clouds are indexed in 2D grids and segments are clustered step probing toward 8-adjacent scanning directions. Then, the saliency of each grid is calculated according to the elevation variance of adjacent segments towards each scanning direction. Subsequently, grids of high ground saliency are considered as candidates for seed point selection and then clustered by region growing. The TPS surface is interpolated for each cluster loosely fitting to the seed points involving an adaptive relative variance coefficient which is according to ground saliency and elevation deviation. And finally, the ground points are extracted around the TPS surface. Experimental results indicate that the proposed SATPS algorithm achieves better Type 1 accuracy and total accuracy than the state-of-the-art algorithms in scenes with complex terrain structures, which is practical to generate DEM products.

Extracting summary statistics of rapid numerical sequences

We examine the ability of observers to extract summary statistics (such as the mean and the relative-variance) from rapid numerical sequences (two digit numbers presented at a rate of 4/sec). In four experiments, we find that the participants show a remarkable ability to extract such summary statistics and that their precision in the estimation of the sequence-mean improves with the sequence-length (subject to individual differences). Using model selection for individual participants we find that, when they only estimate the sequence average, most participants rely on a holistic process of frequency based estimation and there is a minority who rely on a rule-based and capacity limited mid-range strategy. When both the sequence-average and the relative variance is estimated about half of the participants rely on these two strategies. Importantly, the holistic strategy appears more efficient in terms of its precision. We discuss implications for the domains of two pathways numerical processes and decision-making.

An approach of reducing overall level of export fluctuations of the export-oriented countries

Overall level of export fluctuations of the export-oriented countries with rising export volume partly stem from the market failure caused by free choice of export enterprises, some government intervention thus may be necessary. To reduce the level of fluctuations of the export growth rates in these countries, this paper, taking the significant differences of the exports among various markets into account and thus using a new index named relative variance to measure the export volatility risks, proposes a model of merchandise market portfolio, a modified version of Markowitz model, available to provide explicit guidelines for the firms, the industries and even the whole country to optimize the structure of their export markets. An application of this model to the case of China's apple is then discussed. The results show that the market share of China’s apple in 7 sub-markets should be redistributed drastically.

P1744 Motion and velocity of the different parts of the AV plane. Relation to site and wall length

Background Displacement (MAPSE) and peak systolic velocity (S") of the various parts of the mitral annulus differ. Also, both indices are higher in the right ventricular free wall. We aimed to investigate the relations between wall motion, wall lengths and sites in the left ventricle, as well as comparing to the right ventricle to assess the influence on systolic deformation of the AV-plane. Methods The HUNT study examined 1266 subjects without evidence of heart disease from a mixed urban/rural population of North Trøndelag county, S", linear diastolic left ventricular annulus to apex distance (WL) and MAPSE was measured in the septal, anterior, lateral and inferior points of the mitral annulus. Intra individual variance and relative variance (variance / mean) of S" and MAPSE was calculated and compared to the same variance of the values normalised for wall length (S"/WL and MAPSE/WL). Results Wall lengths, velocities and MAPSE are shown in figure 1. Wall lengths were associated with both MAPSE and S". Both wall lengths and motion were greatest in the free walls of the LV, but smallest in the septal parts of the AVplane. Variances are shown in table 1. Even if intra-individual variances are larger for S" than MAPSE, relative variance for both decreased by 80 - 90% when normalised for wall length. Conclusion There is an intra-individual variability of MAPSE and S" of the LV, corresponding to WL, when the values normalised for WL most of the variability disappears. Intra individual variability of strain and strain rate per wall is less than MAPSE and S" as shown earlier. As the apex is located centrally, walls corresponding to the free walls are longer than those closest to the septum, thus motion and wall length are both greatest corresponding to the LV free walls. Motion of the right ventricular free wall was higher than the LV free wall; TAPSE 2.8 cm, and S" 12.6 cm/s as shown previously. The relation of TAPSE and S" of the right ventricle to wall length will be different, as the afterload in the RV is far less. But as both lateral parts of the AV plane move more than the centre, givinga systolic bending of the AV-planealso as the central part of the AV-plane is centrally anchored to the large arteries as shown in fig. 1. Table 1 WL (cm) MAPSE (cm) MAPSE / WL (% points) S" (cm/s) S" / WL (/s) Mean of 4 walls 9.5 1.6 0.16 8.4 0.87 Variance 0.04 0.04 0.0004 1.2 0.01 Relative variance (%) 2.8 2.7 0.25 12.1 1.4 Wall lengths (WL), displacement(MAPSE), Systolic velocity (S") and mAPSE and S" normalised for WL. Means and intra individual variances. Abstract P1744 Figure. Fig. 1

Optimal filtering of multidimensional random fields generated by autoregressions with multiple roots of characteristic equations

The use of mathematical models allows to compare the theoretical expressions and simulation results. Autoregressive random fields can be used for description of the images, however, such models have pronounced anisotropy, and the simulated images are too sharp. The elimination of this drawback is possible through the use of models with multiple roots of characteristic equations. The analysis shows that using models with multiple roots in filtering images with smoothly varying brightness provides smaller errors than the use of autoregressive random fields. However, studies of the dependences of filtering efficiency on various model parameters and signal-to-noise ratios for multidimensional autoregressive random fields were almost not carried out. The article discusses the solution of the problem of optimal filtering of images based on models with multiple roots of characteristic equations. Theoretical dependences of the relative variance of the filtering error on the dimension of random fields are obtained. Furthermore, it was presented some results of filtering real images by such model in comparison with autoregressive model.