Comparison of Support Vector Machine and Extreme Gradient Boosting for predicting daily global solar radiation using temperature and precipitation in humid subtropical climates: A case study in China

Accurate and timely classification and monitoring of urban functional zones prove to be significant in rapidly developing cities, to better understand the real and varying urban functions of cities to support urban planning and management. Many efforts have been undertaken to identify urban functional zones using various classification approaches and multi-source geospatial datasets. The complexity of this category of classification poses tremendous challenges to these studies especially in terms of classification accuracy, but on the opposite, the rapid development of machine learning technologies provides us with new opportunities. In this study, a set of commonly used urban functional zones classification approaches, including Multinomial Logistic Regression, K-Nearest Neighbors, Decision Tree, Support Vector Machine (SVM), and Random Forest, are examined and compared with the newly developed eXtreme Gradient Boosting (XGBoost) model, using the case study of Yuzhong District, Chongqing, China. The investigation is based on multi-variate geospatial data, including night-time imagery, geotagged Weibo data, points of interest (POI) from Gaode, and Baidu Heat Map. This study is the first endeavor of implementing the XGBoost model in the field of urban functional zones classification. The results suggest that the XGBoost classification model performed the best and was able to achieve an accuracy of 88.05%, which is significantly higher than the other commonly used approaches. In addition, the integration of night-time imagery, geotagged Weibo data, POI from Gaode, and Baidu Heat Map has also demonstrated their values for the classification of urban functional zones in this case study.

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Hierarchical attention networks for information extraction from cancer pathology reports

Journal of the American Medical Informatics Association ◽

10.1093/jamia/ocx131 ◽

2017 ◽

Vol 25 (3) ◽

pp. 321-330 ◽

Cited By ~ 29

Author(s):

Shang Gao ◽

Michael T Young ◽

John X Qiu ◽

Hong-Jun Yoon ◽

James B Christian ◽

...

Keyword(s):

Neural Network ◽

Support Vector Machine ◽

Information Extraction ◽

Model Performance ◽

Gradient Boosting ◽

Support Vector ◽

Attention Networks ◽

Cancer Pathology ◽

Extreme Gradient Boosting ◽

Pathology Reports

Abstract Objective We explored how a deep learning (DL) approach based on hierarchical attention networks (HANs) can improve model performance for multiple information extraction tasks from unstructured cancer pathology reports compared to conventional methods that do not sufﬁciently capture syntactic and semantic contexts from free-text documents. Materials and Methods Data for our analyses were obtained from 942 deidentiﬁed pathology reports collected by the National Cancer Institute Surveillance, Epidemiology, and End Results program. The HAN was implemented for 2 information extraction tasks: (1) primary site, matched to 12 International Classification of Diseases for Oncology topography codes (7 breast, 5 lung primary sites), and (2) histological grade classiﬁcation, matched to G1–G4. Model performance metrics were compared to conventional machine learning (ML) approaches including naive Bayes, logistic regression, support vector machine, random forest, and extreme gradient boosting, and other DL models, including a recurrent neural network (RNN), a recurrent neural network with attention (RNN w/A), and a convolutional neural network. Results Our results demonstrate that for both information tasks, HAN performed signiﬁcantly better compared to the conventional ML and DL techniques. In particular, across the 2 tasks, the mean micro and macroF-scores for the HAN with pretraining were (0.852,0.708), compared to naive Bayes (0.518, 0.213), logistic regression (0.682, 0.453), support vector machine (0.634, 0.434), random forest (0.698, 0.508), extreme gradient boosting (0.696, 0.522), RNN (0.505, 0.301), RNN w/A (0.637, 0.471), and convolutional neural network (0.714, 0.460). Conclusions HAN-based DL models show promise in information abstraction tasks within unstructured clinical pathology reports.

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A support vector machine–firefly algorithm-based model for global solar radiation prediction

Solar Energy ◽

10.1016/j.solener.2015.03.015 ◽

2015 ◽

Vol 115 ◽

pp. 632-644 ◽

Cited By ~ 167

Author(s):

Lanre Olatomiwa ◽

Saad Mekhilef ◽

Shahaboddin Shamshirband ◽

Kasra Mohammadi ◽

Dalibor Petković ◽

...

Keyword(s):

Support Vector Machine ◽

Solar Radiation ◽

Firefly Algorithm ◽

Global Solar Radiation ◽

Support Vector

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Modelos de machine learning para predição do sucesso de startups

Revista de Gestão e Projetos ◽

10.5585/gep.v12i2.18942 ◽

2021 ◽

Vol 12 (2) ◽

pp. 28-55

Author(s):

Fabiano Rodrigues ◽

Francisco Aparecido Rodrigues ◽

Thelma Valéria Rocha Rodrigues

Keyword(s):

Machine Learning ◽

Support Vector Machine ◽

Random Forest ◽

Decision Tree ◽

Initial Public Offering ◽

Gradient Boosting ◽

Support Vector ◽

Trade Offs ◽

Extreme Gradient Boosting ◽

Public Offering

Este estudo analisa resultados obtidos com modelos de machine learning para predição do sucesso de startups. Como proxy de sucesso considera-se a perspectiva do investidor, na qual a aquisição da startup ou realização de IPO (Initial Public Offering) são formas de recuperação do investimento. A revisão da literatura aborda startups e veículos de financiamento, estudos anteriores sobre predição do sucesso de startups via modelos de machine learning, e trade-offs entre técnicas de machine learning. Na parte empírica, foi realizada uma pesquisa quantitativa baseada em dados secundários oriundos da plataforma americana Crunchbase, com startups de 171 países. O design de pesquisa estabeleceu como filtro startups fundadas entre junho/2010 e junho/2015, e uma janela de predição entre junho/2015 e junho/2020 para prever o sucesso das startups. A amostra utilizada, após etapa de pré-processamento dos dados, foi de 18.571 startups. Foram utilizados seis modelos de classificação binária para a predição: Regressão Logística, Decision Tree, Random Forest, Extreme Gradiente Boosting, Support Vector Machine e Rede Neural. Ao final, os modelos Random Forest e Extreme Gradient Boosting apresentaram os melhores desempenhos na tarefa de classificação. Este artigo, envolvendo machine learning e startups, contribui para áreas de pesquisa híbridas ao mesclar os campos da Administração e Ciência de Dados. Além disso, contribui para investidores com uma ferramenta de mapeamento inicial de startups na busca de targets com maior probabilidade de sucesso.

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