scale selection
Recently Published Documents


TOTAL DOCUMENTS

250
(FIVE YEARS 47)

H-INDEX

29
(FIVE YEARS 2)

2022 ◽  
Author(s):  
Neil Hester ◽  
Jordan Axt ◽  
Eric Hehman

Racial attitudes, beliefs, and motivations lie at the center of many of the most influential theories of prejudice and discrimination. The extent to which such theories can meaningfully explain behavior hinges on accurate measurement of these latent constructs. We evaluated the validity properties of 25 race-related scales in a sample of 1,031,207 respondents using modern approaches such as dynamic fit indices, Item Response Theory, and nomological nets. Despite showing adequate internal reliability, many scales demonstrated poor model fit and had latent score distributions showing clear floor or ceiling effects, results that illustrate deficiencies in measures’ ability to capture their intended construct. Nomological nets further suggested that the theoretical space of “racial prejudice” is crowded with scales that may not actually capture meaningfully distinct latent constructs. We provide concrete recommendations for scale selection and renovation and outline implications for overlooking measurement issues in the study of prejudice and discrimination.


Sensors ◽  
2021 ◽  
Vol 21 (23) ◽  
pp. 7935
Author(s):  
Shuang Hao ◽  
Yuhuan Cui ◽  
Jie Wang

High-spatial-resolution images play an important role in land cover classification, and object-based image analysis (OBIA) presents a good method of processing high-spatial-resolution images. Segmentation, as the most important premise of OBIA, significantly affects the image classification and target recognition results. However, scale selection for image segmentation is difficult and complicated for OBIA. The main challenge in image segmentation is the selection of the optimal segmentation parameters and an algorithm that can effectively extract the image information. This paper presents an approach that can effectively select an optimal segmentation scale based on land object average areas. First, 20 different segmentation scales were used for image segmentation. Next, the classification and regression tree model (CART) was used for image classification based on 20 different segmentation results, where four types of features were calculated and used, including image spectral bands value, texture value, vegetation indices, and spatial feature indices, respectively. WorldView-3 images were used as the experimental data to verify the validity of the proposed method for the selection of the optimal segmentation scale parameter. In order to decide the effect of the segmentation scale on the object area level, the average areas of different land objects were estimated based on the classification results. Experiments based on the multi-scale segmentation scale testify to the validity of the land object’s average area-based method for the selection of optimal segmentation scale parameters. The study results indicated that segmentation scales are strongly correlated with an object’s average area, and thus, the optimal segmentation scale of every land object can be obtained. In this regard, we conclude that the area-based segmentation scale selection method is suitable to determine optimal segmentation parameters for different land objects. We hope the segmentation scale selection method used in this study can be further extended and used for different image segmentation algorithms.


2021 ◽  
Author(s):  
Yingjie Zhu ◽  
Bin Yang

Abstract Hierarchical structured data are very common for data mining and other tasks in real-life world. How to select the optimal scale combination from a multi-scale decision table is critical for subsequent tasks. At present, the models for calculating the optimal scale combination mainly include lattice model, complement model and stepwise optimal scale selection model, which are mainly based on consistent multi-scale decision tables. The optimal scale selection model for inconsistent multi-scale decision tables has not been given. Based on this, firstly, this paper introduces the concept of complement and lattice model proposed by Li and Hu. Secondly, based on the concept of positive region consistency of inconsistent multi-scale decision tables, the paper proposes complement model and lattice model based on positive region consistent and gives the algorithm. Finally, some numerical experiments are employed to verify that the model has the same properties in processing inconsistent multi-scale decision tables as the complement model and lattice model in processing consistent multi-scale decision tables. And for the consistent multi-scale decision table, the same results can be obtained by using the model based on positive region consistent. However, the lattice model based on positive region consistent is more time-consuming and costly. The model proposed in this paper provides a new theoretical method for the optimal scale combination selection of the inconsistent multi-scale decision table.


2021 ◽  
Vol 5 (3) ◽  
pp. 127
Author(s):  
Christos G. Karydas

In this research, the geographic, observational, functional, and cartographic scale is unified into a single mathematical formulation for the purposes of earth observation image classification. Fractal analysis is used to define functional scales, which then are linked to the other concepts of scale using common equations and conditions. The proposed formulation is called Unified Scale Theorem (UST), and was assessed with Sentinel-2 image covering a variety of land uses from the broad area of Thessaloniki, Greece. Provided as an interactive excel spreadsheet, UST promotes objectivity, rapidity, and accuracy, thus facilitating optimal scale selection for image classification purposes.


2021 ◽  
Vol 92 ◽  
pp. 107107
Author(s):  
Haoran Wang ◽  
Wentao Li ◽  
Tao Zhan ◽  
Kehua Yuan ◽  
Xingchen Hu

2021 ◽  
Vol 130 ◽  
pp. 170-191
Author(s):  
Bing Huang ◽  
Huaxiong Li ◽  
Guofu Feng ◽  
Chunxiang Guo ◽  
Dafeng Chen

Sign in / Sign up

Export Citation Format

Share Document