scholarly journals Incident atrial fibrillation and its risk prediction in patients developing COVID-19: A machine learning based algorithm approach

2021 ◽  
Author(s):  
Ash Genaidy
Keyword(s):  
Machine Learning ◽  
The Elderly ◽  
Adverse Outcomes ◽  
Good Prediction ◽  
Main Effect Model ◽  
Effect Model ◽  
Main Effect ◽  
Index Value ◽  
Treat All ◽  
Better Than

Background The elderly multi-morbid patient is at high risk of adverse outcomes with COVID-19 complications, and in the general population, the development of incident AF is associated with worse outcomes in such patients. We therefore investigated incident AF risks in a large prospective population of elderly patients with/without incident COVID-19 cases and baseline cardiovascular/non-cardiovascular multi-morbidities. We used two approaches: main-effect modeling and secondly, a machine-learning (ML) approach accounting for complex dynamic relationships. Methods We studied a prospective elderly US cohort of 280592 patients from medical databases in a 8-month investigation of new COVID19 cases. Incident AF outcomes were examined in relationship to diverse multi-morbid conditions, COVID-19 status and demographic variables, with ML accounting for the dynamic nature of changing multimorbidity risk factors. Results Multi-morbidity contributed to the onset of confirmed COVID-19 cases with cognitive impairment (OR 1.69; 95%CI 1.52-1.88), anemia (OR 1.41; 95%CI 1.32-1.50), diabetes mellitus (OR 1.35; 95%CI 1.27-1.44) and vascular disease (OR 1.30; 95%CI 1.21-1.39) having the highest associations. A main effect model (C-index value 0.718) showed that COVID-19 had the highest association with incident AF cases (OR 3.12; 95%CI 2.61-3.710, followed by congestive heart failure (1.72; 95%CI 1.50-1.96), then coronary artery disease (OR 1.43; 95%CI 1.27-1.60) and valvular disease (1.42; 95%CI 1.26-1.60). The ML algorithm demonstrated improved discriminatory validity incrementally over the statistical main effect model (training: C-index 0.729, 95%CI 0.718-0.740; validation: C-index 0.704, 95%CI 0.687-0.72). Calibration of ML based formulation was satisfactory and better than the main-effect model. Decision curve analysis demonstrated that the clinical utility for the ML based formulation was better than the ‘treat all’ strategy and the main effect model. Conclusion COVID-19 status has major implications for incident AF in a cohort with diverse cardiovascular/non-cardiovascular multi-morbidities. Our approach accounting for dynamic multimorbidity changes had good prediction for incident AF amongst incident COVID19 cases.

Soutien social et symptômes dépressifs au sein des personnes âgées

1992 ◽  
Vol 11 (4) ◽  
pp. 322-346 ◽  
Author(s):  
Philippe Landreville ◽  
Philippe Cappeliez
Keyword(s):  
Social Support ◽  
Depressive Symptoms ◽  
The Elderly ◽  
Elderly Persons ◽  
Social Variables ◽  
Buffering Effect ◽  
Main Effect Model ◽  
Effect Model ◽  
Main Effect ◽  
The Relationship

ABSTRACTThere is great interest in identifying psychological and social variables associated with depressive symptoms in older adults. The goal of this article is to review the literature on the relationship between social support and depressive symptoms in the elderly and to identify the mechanisms involved in this relationship. The review indicates that both structural and functional dimensions of social support are inversely related to depressive symptoms in elderly persons. In addition, there is evidence supporting both the main effect model and the buffering effect model of social support. It is unclear, however, whether observation of these effects depends on the type of measure used to assess social support. A better understanding of the relationship between social support and depression requires the consideration of more precise dimensions of social support as well as the nature of the Stressors experienced by older people.

Childhood Physical Abuse, Perceived Social Support, and Socioemotional Status in Adult Women

1995 ◽  
Vol 10 (4) ◽  
pp. 273-283 ◽  
Author(s):  
Julie L. Crouch ◽  
Joel S. Milner ◽  
John A. Caliso
Keyword(s):  
Social Support ◽  
Child Abuse ◽  
Physical Abuse ◽  
Perceived Social Support ◽  
Abuse Potential ◽  
Adult Women ◽  
Child Abuse Potential ◽  
Main Effect Model ◽  
Effect Model ◽  
Main Effect

This study investigated the extent to which an interactional model, relative to a main effect model, predicts the relationship between childhood physical abuse, perceived social support, and various aspects of socioemotional functioning in adult women. The results indicated that perceived social support during childhood was significantly related to subsequent levels of adult depression, trait anxiety, and child abuse potential in a manner consistent with a main effect model. Childhood history of physical abuse was related only to adult child abuse potential. Implications and study limitations are discussed.

On the Marginal Dependency of Cohen’s κ

2008 ◽  
Vol 13 (4) ◽  
pp. 305-315 ◽  
Author(s):  
Alexander von Eye ◽  
Maxine von Eye
Keyword(s):  
Probability Distributions ◽  
Null Model ◽  
Marginal Probability ◽  
Rater Agreement ◽  
Marginal Distributions ◽  
Linear Interaction ◽  
Main Effect Model ◽  
Effect Model ◽  
Main Effect ◽  
Log Linear

Cohen’s κ (kappa) is typically used as a measure of degree of rater agreement. It is often criticized because it is marginal-dependent. In this article, this characteristic is explained and illustrated in the context of (1) nonuniform marginal probability distributions, (2) odds ratios that remain constant while κ changes in the presence of varying marginal distributions, and (3) percentages of raw agreement that remain constant while κ changes in the presence of varying marginal distributions. The meaning and interpretation of κ are explained with reference to the log-linear main effect model of variable independence. This model is used for the estimation of the expected cell frequencies of agreement tables. It is shown that the interpretation of κ as a measure of degree of agreement is incorrect. The correct interpretation is that κ assesses the degree of agreement beyond that expected based on a statistical model such as the independence or the null model. Based on Goodman’s (1991) distinction between marginal-free and marginal-dependent measures, it is shown that κ is marginal-dependent. It shares this characteristic with the well-known χ2-statistic and the correlation coefficient for cross-classifications. In contrast, the odds ratio, the unweighted log-linear interaction, and the percentage of raw agreement are marginal-free. Therefore, the expectation that marginal-dependent κ would reflect the same data characteristics as some of the marginal-free measures is misguided. It is recommended that researchers report both measures of degree of agreement and measures of agreement beyond some expectation.

Exploring the Use of Machine Learning to Automate the Qualitative Coding of Church-related Tweets

2020 ◽  
Vol 14 (2) ◽  
pp. 140-159
Author(s):  
Anthony-Paul Cooper ◽  
Emmanuel Awuni Kolog ◽  
Erkki Sutinen
Keyword(s):  
Machine Learning ◽  
Online Community ◽  
High Volume ◽  
Machine Learning Algorithms ◽  
Supervised Machine Learning ◽  
Social Media Data ◽  
Twitter Data ◽  
Resource Intensity ◽  
Media Data ◽  
Better Than

This article builds on previous research around the exploration of the content of church-related tweets. It does so by exploring whether the qualitative thematic coding of such tweets can, in part, be automated by the use of machine learning. It compares three supervised machine learning algorithms to understand how useful each algorithm is at a classification task, based on a dataset of human-coded church-related tweets. The study finds that one such algorithm, Naïve-Bayes, performs better than the other algorithms considered, returning Precision, Recall and F-measure values which each exceed an acceptable threshold of 70%. This has far-reaching consequences at a time where the high volume of social media data, in this case, Twitter data, means that the resource-intensity of manual coding approaches can act as a barrier to understanding how the online community interacts with, and talks about, church. The findings presented in this article offer a way forward for scholars of digital theology to better understand the content of online church discourse.

Identification of Anti-cancer Peptides Based on Multi-classifier System

2020 ◽  
Vol 22 (10) ◽  
pp. 694-704 ◽  
Author(s):  
Wanben Zhong ◽  
Bineng Zhong ◽  
Hongbo Zhang ◽  
Ziyi Chen ◽  
Yan Chen
Keyword(s):  
Machine Learning ◽  
Side Effect ◽  
Learning Models ◽  
Normal Cells ◽  
Classifier System ◽  
Prediction Rate ◽  
Anti Cancer ◽  
Feature Information ◽  
Machine Learning Models ◽  
Better Than

Aim and Objective: Cancer is one of the deadliest diseases, taking the lives of millions every year. Traditional methods of treating cancer are expensive and toxic to normal cells. Fortunately, anti-cancer peptides (ACPs) can eliminate this side effect. However, the identification and development of new anti Materials and Methods: In our study, a multi-classifier system was used, combined with multiple machine learning models, to predict anti-cancer peptides. These individual learners are composed of different feature information and algorithms, and form a multi-classifier system by voting. Results and Conclusion: The experiments show that the overall prediction rate of each individual learner is above 80% and the overall accuracy of multi-classifier system for anti-cancer peptides prediction can reach 95.93%, which is better than the existing prediction model.

Computing Possible Futures

2019 ◽  
Author(s):  
William B. Rouse
Keyword(s):  
Artificial Intelligence ◽  
Machine Learning ◽  
Computational Modeling ◽  
Mental Model ◽  
Data Analytics ◽  
Computational Models ◽  
Senior Managers ◽  
Interactive Visualizations ◽  
Use Of Models ◽  
Better Than

This book discusses the use of models and interactive visualizations to explore designs of systems and policies in determining whether such designs would be effective. Executives and senior managers are very interested in what “data analytics” can do for them and, quite recently, what the prospects are for artificial intelligence and machine learning. They want to understand and then invest wisely. They are reasonably skeptical, having experienced overselling and under-delivery. They ask about reasonable and realistic expectations. Their concern is with the futurity of decisions they are currently entertaining. They cannot fully address this concern empirically. Thus, they need some way to make predictions. The problem is that one rarely can predict exactly what will happen, only what might happen. To overcome this limitation, executives can be provided predictions of possible futures and the conditions under which each scenario is likely to emerge. Models can help them to understand these possible futures. Most executives find such candor refreshing, perhaps even liberating. Their job becomes one of imagining and designing a portfolio of possible futures, assisted by interactive computational models. Understanding and managing uncertainty is central to their job. Indeed, doing this better than competitors is a hallmark of success. This book is intended to help them understand what fundamentally needs to be done, why it needs to be done, and how to do it. The hope is that readers will discuss this book and develop a “shared mental model” of computational modeling in the process, which will greatly enhance their chances of success.

scholarly journals NLOS Multipath Classification of GNSS Signal Correlation Output Using Machine Learning

Sensors ◽  
2021 ◽  
Vol 21 (7) ◽  
pp. 2503
Author(s):  
Taro Suzuki ◽  
Yoshiharu Amano
Keyword(s):  
Machine Learning ◽  
Satellite System ◽  
Training Data ◽  
Support Vector ◽  
Positioning Errors ◽  
Automated Method ◽  
Global Navigation Satellite ◽  
Better Than ◽  
Signal Correlation

This paper proposes a method for detecting non-line-of-sight (NLOS) multipath, which causes large positioning errors in a global navigation satellite system (GNSS). We use GNSS signal correlation output, which is the most primitive GNSS signal processing output, to detect NLOS multipath based on machine learning. The shape of the multi-correlator outputs is distorted due to the NLOS multipath. The features of the shape of the multi-correlator are used to discriminate the NLOS multipath. We implement two supervised learning methods, a support vector machine (SVM) and a neural network (NN), and compare their performance. In addition, we also propose an automated method of collecting training data for LOS and NLOS signals of machine learning. The evaluation of the proposed NLOS detection method in an urban environment confirmed that NN was better than SVM, and 97.7% of NLOS signals were correctly discriminated.

scholarly journals Machine Learning for the Dynamic Positioning of UAVs for Extended Connectivity

Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4618
Author(s):  
Francisco Oliveira ◽  
Miguel Luís ◽  
Susana Sargento
Keyword(s):  
Machine Learning ◽  
Cellular Networks ◽  
Real Data ◽  
Emerging Technology ◽  
Machine Learning Algorithms ◽  
Base Stations ◽  
Aerial Vehicle ◽  
Positioning Algorithm ◽  
The Military ◽  
Better Than

Unmanned Aerial Vehicle (UAV) networks are an emerging technology, useful not only for the military, but also for public and civil purposes. Their versatility provides advantages in situations where an existing network cannot support all requirements of its users, either because of an exceptionally big number of users, or because of the failure of one or more ground base stations. Networks of UAVs can reinforce these cellular networks where needed, redirecting the traffic to available ground stations. Using machine learning algorithms to predict overloaded traffic areas, we propose a UAV positioning algorithm responsible for determining suitable positions for the UAVs, with the objective of a more balanced redistribution of traffic, to avoid saturated base stations and decrease the number of users without a connection. The tests performed with real data of user connections through base stations show that, in less restrictive network conditions, the algorithm to dynamically place the UAVs performs significantly better than in more restrictive conditions, reducing significantly the number of users without a connection. We also conclude that the accuracy of the prediction is a very important factor, not only in the reduction of users without a connection, but also on the number of UAVs deployed.

scholarly journals 174 A comparison of machine learning algorithms in the classification of beef steers finished in feedlot

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 126-127
Author(s):  
Lucas S Lopes ◽  
Christine F Baes ◽  
Dan Tulpan ◽  
Luis Artur Loyola Chardulo ◽  
Otavio Machado Neto ◽  
...  
Keyword(s):  
Machine Learning ◽  
Decision Tree ◽  
Learning Algorithms ◽  
Machine Learning Algorithms ◽  
Final Decision ◽  
Relevant Parameter ◽  
Good Prediction ◽  
Quality Traits ◽  
C4.5 Decision Tree

Abstract The aim of this project is to compare some of the state-of-the-art machine learning algorithms on the classification of steers finished in feedlots based on performance, carcass and meat quality traits. The precise classification of animals allows for fast, real-time decision making in animal food industry, such as culling or retention of herd animals. Beef production presents high variability in its numerous carcass and beef quality traits. Machine learning algorithms and software provide an opportunity to evaluate the interactions between traits to better classify animals. Four different treatment levels of wet distiller’s grain were applied to 97 Angus-Nellore animals and used as features for the classification problem. The C4.5 decision tree, Naïve Bayes (NB), Random Forest (RF) and Multilayer Perceptron (MLP) Artificial Neural Network algorithms were used to predict and classify the animals based on recorded traits measurements, which include initial and final weights, sheer force and meat color. The top performing classifier was the C4.5 decision tree algorithm with a classification accuracy of 96.90%, while the RF, the MLP and NB classifiers had accuracies of 55.67%, 39.17% and 29.89% respectively. We observed that the final decision tree model constructed with C4.5 selected only the dry matter intake (DMI) feature as a differentiator. When DMI was removed, no other feature or combination of features was sufficiently strong to provide good prediction accuracies for any of the classifiers. We plan to investigate in a follow-up study on a significantly larger sample size, the reasons behind DMI being a more relevant parameter than the other measurements.

Sign in / Sign up

Export Citation Format

Share Document