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Tytuł:
A comparative study on performance of basic and ensemble classifiers with various datasets
Autorzy:
Gunakala, Archana
Shahid, Afzal Hussain
Powiązania:
https://bibliotekanauki.pl/articles/30148255.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Promocji Wiedzy
Tematy:
classification
Naïve Bayes
neural network
Support Vector Machine
Decision Tree
ensemble learning
Random Forest
Opis:
Classification plays a critical role in machine learning (ML) systems for processing images, text and high -dimensional data. Predicting class labels from training data is the primary goal of classification. An optimal model for a particular classification problem is chosen based on the model's performance and execution time. This paper compares and analyzes the performance of basic as well as ensemble classifiers utilizing 10-fold cross validation and also discusses their essential concepts, advantages, and disadvantages. In this study five basic classifiers namely Naïve Bayes (NB), Multi-layer Perceptron (MLP), Support Vector Machine (SVM), Decision Tree (DT), and Random Forest (RF) and the ensemble of all the five classifiers along with few more combinations are compared with five University of California Irvine (UCI) ML Repository datasets and a Diabetes Health Indicators dataset from Kaggle repository. To analyze and compare the performance of classifiers, evaluation metrics like Accuracy, Recall, Precision, Area Under Curve (AUC) and F-Score are used. Experimental results showed that SVM performs best on two out of the six datasets (Diabetes Health Indicators and waveform), RF performs best for Arrhythmia, Sonar, Tic-tac-toe datasets, and the best ensemble combination is found to be DT+SVM+RF on Ionosphere dataset having respective accuracies 72.58%, 90.38%, 81.63%, 73.59%, 94.78% and 94.01%. The proposed ensemble combinations outperformed the conven¬tional models for few datasets.
Źródło:
Applied Computer Science; 2023, 19, 1; 107-132
1895-3735
2353-6977
Pojawia się w:
Applied Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Machine Learning Model for Improving Building Detection in Informal Areas: A Case Study of Greater Cairo
Autorzy:
Taha, Lamyaa Gamal El-deen
Ibrahim, Rania Elsayed
Powiązania:
https://bibliotekanauki.pl/articles/2055780.pdf
Data publikacji:
2022
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
multi-source image fusion
random forest
support vector machine
DEM extraction
unplanned unsafe areas
remote sensing
Opis:
Building detection in Ashwa’iyyat is a fundamental yet challenging problem, mainly because it requires the correct recovery of building footprints from images with high-object density and scene complexity. A classification model was proposed to integrate spectral, height and textural features. It was developed for the automatic detection of the rectangular, irregular structure and quite small size buildings or buildings which are close to each other but not adjoined. It is intended to improve the precision with which buildings are classified using scikit learn Python libraries and QGIS. WorldView-2 and Spot-5 imagery were combined using three image fusion techniques. The Grey-Level Co-occurrence Matrix was applied to determine which attributes are important in detecting and extracting buildings. The Normalized Digital Surface Model was also generated with 0.5-m resolution. The results demonstrated that when textural features of colour images were introduced as classifier input, the overall accuracy was improved in most cases. The results show that the proposed model was more accurate and efficient than the state-of-the-art methods and can be used effectively to extract the boundaries of small size buildings. The use of a classifier ensample is recommended for the extraction of buildings.
Źródło:
Geomatics and Environmental Engineering; 2022, 16, 2; 39--58
1898-1135
Pojawia się w:
Geomatics and Environmental Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
About the density of spectral measure of the two-dimensional SaS random vector
Autorzy:
Borowiecka-Olszewska, Marta
Misiewicz, Jolanta
Powiązania:
https://bibliotekanauki.pl/articles/729784.pdf
Data publikacji:
2003
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
stable
sub-stable
maximal stable random vector
spectral measure
Opis:
In this paper, we consider a symmetric α-stable p-sub-stable two-dimensional random vector. Our purpose is to show when the function $exp{-(|a|p + |b|p)^{α/p}}$ is a characteristic function of such a vector for some p and α. The solution of this problem we can find in [3], in the language of isometric embeddings of Banach spaces. Our proof is based on simple properties of stable distributions and some characterization given in [4].
Źródło:
Discussiones Mathematicae Probability and Statistics; 2003, 23, 1; 77-81
1509-9423
Pojawia się w:
Discussiones Mathematicae Probability and Statistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acoustic intensity vector generated by vibrating set of small areas with random amplitudes
Wektor natężenia akustycznego generowany przez układ małych płaskich elementów drgających z losowymi amplitudami
Autorzy:
Kozień, M. S.
Powiązania:
https://bibliotekanauki.pl/articles/281747.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
acoustic radiation
random vibrations
sound intensity vector
structural noise
Opis:
The paper presents a generalisation of the hybrid method of estimation of sound radiated by vibrating surfaces, formulated previously for the deterministic case of random vibrations. The analysis is made for random amplitudes of vibrations in a narrow frequency band. The results show complexity of the analysis in comparison with the deterministic case. Therefore, the method does not seem to be efficient, like the deterministic one, in engineering applications.
W artykule omówiono rozszerzenie metody hybrydowej oszacowania dźwięku promieniowanego przez drgające powierzchnie, sformułowanej pierwotnie dla przypadku drgań deterministycznych, na przypadek drgań losowych. Rozważono przypadek drgań z losowo zmienną amplitudą w wąskim paśmie częstotliwości. Rezultaty analiz pokazują złożoność uzyskanych formuł w stosunku do zagadnień deterministycznych. Dlatego też wydaje się, że metoda ta w prezentowanym podejściu nie jest tak użyteczna w zastosowaniach inżynierskich, jak to ma miejsce w sformułowaniu deterministycznym.
Źródło:
Journal of Theoretical and Applied Mechanics; 2009, 47, 2; 411-420
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Artificial Intelligence Based Flood Forecasting for River Hunza at Danyor Station in Pakistan
Autorzy:
Yaseen, Muhammad Waseem
Awais, Muhammad
Riaz, Khuram
Rasheed, Muhammad Babar
Waqar, Muhammad
Rasheed, Sajid
Powiązania:
https://bibliotekanauki.pl/articles/31340346.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
hydrometeorology
random forest
support vector
multilayer perceptron
machine learning
flood forecasting
Opis:
Floods can cause significant problems for humans and can damage the economy. Implementing a reliable flood monitoring warning system in risk areas can help to reduce the negative impacts of these natural disasters. Artificial intelligence algorithms and statistical approaches are employed by researchers to enhance flood forecasting. In this study, a dataset was created using unique features measured by sensors along the Hunza River in Pakistan over the past 31 years. The dataset was used for classification and regression problems. Two types of machine learning algorithms were tested for classification: classical algorithms (Random Forest, RF and Support Vector Classifier, SVC) and deep learning algorithms (Multi-Layer Perceptron, MLP). For the regression problem, the result of MLP and Support Vector Regression (SVR) algorithms were compared based on their mean square, root mean square and mean absolute errors. The results obtained show that the accuracy of the RF classifier is 0.99, while the accuracies of the SVC and MLP methods are 0.98; moreover, in the case of flood prediction, the SVR algorithm outperforms the MLP approach.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2022, 69, 1; 59-77
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of Approaches for the Extraction of Building Footprints from Pléiades Images
Autorzy:
Taha, Lamyaa Gamal El-deen
Ibrahim, Rania Elsayed
Powiązania:
https://bibliotekanauki.pl/articles/1837996.pdf
Data publikacji:
2021
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
ensemble classifiers
machine learning
random forest
maximum likelihood
support vector machines
backpropagation
image classification
Opis:
The Marina area represents an official new gateway of entry to Egypt and the development of infrastructure is proceeding rapidly in this region. The objective of this research is to obtain building data by means of automated extraction from Pléiades satellite images. This is due to the need for efficient mapping and updating of geodatabases for urban planning and touristic development. It compares the performance of random forest algorithm to other classifiers like maximum likelihood, support vector machines, and backpropagation neural networks over the well-organized buildings which appeared in the satellite images. Images were subsequently classified into two classes: buildings and non-buildings. In addition, basic morphological operations such as opening and closing were used to enhance the smoothness and connectedness of the classified imagery. The overall accuracy for random forest, maximum likelihood, support vector machines, and backpropagation were 97%, 95%, 93% and 92% respectively. It was found that random forest was the best option, followed by maximum likelihood, while the least effective was the backpropagation neural network. The completeness and correctness of the detected buildings were evaluated. Experiments confirmed that the four classification methods can effectively and accurately detect 100% of buildings from very high-resolution images. It is encouraged to use machine learning algorithms for object detection and extraction from very high-resolution images.
Źródło:
Geomatics and Environmental Engineering; 2021, 15, 4; 101-116
1898-1135
Pojawia się w:
Geomatics and Environmental Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Attribute selection for stroke prediction
Autorzy:
Zdrodowska, Małgorzata
Powiązania:
https://bibliotekanauki.pl/articles/386466.pdf
Data publikacji:
2019
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
data mining
classifier
J48 (C4.5)
CART
PART
naive Bayes classifier
random forest
support vector machine
multilayer perceptron
haemorrhagic stroke
ischemic stroke
Opis:
Stroke is the third most common cause of death and the most common cause of long-term disability among adults around theworld. Therefore, stroke prediction and diagnosis is a very important issue. Data mining techniques come in handy to help determine the correlations between individual patient characterisation data, that is, extract from the medical information system the knowledge necessary to predict and treat various diseases. The study analysed the data of patients with stroke using eight known classification algorithms (J48 (C4.5), CART, PART, naive Bayes classifier, Random Forest, Supporting Vector Machine and neural networks Multilayer Perceptron), which allowed to build an exploration model given with an accuracy of over 88%. The potential features of patients, which may be factors that increase the risk of stroke, were also indicated.
Źródło:
Acta Mechanica et Automatica; 2019, 13, 3; 200-204
1898-4088
2300-5319
Pojawia się w:
Acta Mechanica et Automatica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Automatic speech based emotion recognition using paralinguistics features
Autorzy:
Hook, J.
Noroozi, F.
Toygar, O.
Anbarjafari, G.
Powiązania:
https://bibliotekanauki.pl/articles/200261.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
random forests
speech emotion recognition
machine learning
support vector machines
lasy
rozpoznawanie emocji mowy
nauczanie maszynowe
Opis:
Affective computing studies and develops systems capable of detecting humans affects. The search for universal well-performing features for speech-based emotion recognition is ongoing. In this paper, a?small set of features with support vector machines as the classifier is evaluated on Surrey Audio-Visual Expressed Emotion database, Berlin Database of Emotional Speech, Polish Emotional Speech database and Serbian emotional speech database. It is shown that a?set of 87 features can offer results on-par with state-of-the-art, yielding 80.21, 88.6, 75.42 and 93.41% average emotion recognition rate, respectively. In addition, an experiment is conducted to explore the significance of gender in emotion recognition using random forests. Two models, trained on the first and second database, respectively, and four speakers were used to determine the effects. It is seen that the feature set used in this work performs well for both male and female speakers, yielding approximately 27% average emotion recognition in both models. In addition, the emotions for female speakers were recognized 18% of the time in the first model and 29% in the second. A?similar effect is seen with male speakers: the first model yields 36%, the second 28% a?verage emotion recognition rate. This illustrates the relationship between the constitution of training data and emotion recognition accuracy.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2019, 67, 3; 479-488
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Band copulas as spectral measures for two-dimensional stable random vectors
Autorzy:
Bojarski, Jacek
K. Misiewicz, Jolanta
Powiązania:
https://bibliotekanauki.pl/articles/729780.pdf
Data publikacji:
2003
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
Symmetric stable random vector
spectral measure
canonical spectral measure
copula
James corelation for random variables
Opis:
In this paper, we study basic properties of symmetric stable random vectors for which the spectral measure is a copula, i.e., a distribution having uniformly distributed marginals.
Źródło:
Discussiones Mathematicae Probability and Statistics; 2003, 23, 1; 69-75
1509-9423
Pojawia się w:
Discussiones Mathematicae Probability and Statistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Charakterystyki wielowymiarowych wielkości finansowych oparte na definicji potęgi wektora
Characteristics of Multivariate Financial Items Based on Definition of the Power of a Vector
Autorzy:
Budny, Katarzyna
Tatar, Jan
Powiązania:
https://bibliotekanauki.pl/articles/591516.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Ekonomiczny w Katowicach
Tematy:
Analiza matematyczna
Analiza wielowymiarowa
Fundusze inwestycyjne
Portfel inwestycyjny
Wektor losowy
Investment funds
Investment portfolio
Mathematical analysis
Multi-dimensional analysis
Random vector
Opis:
In the previous articles the authors proposed - different from the well-known in the probabilistic literature - definitions of such characteristics of multivariate probability distributions as the expected value, variance, standard deviation, skewness coefficient, kurtosis and excess kurtosis. The basis of these definitions is the concept of the power of the vector in an inner product space proposed by J. Tatar, among others things, in Tatar (1996b). In this paper, the formal forms of those which are mentioned above are used to describe some random vectors occurring in a typical financial market. In this case these.
Źródło:
Studia Ekonomiczne; 2014, 189; 27-39
2083-8611
Pojawia się w:
Studia Ekonomiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Classifiers accuracy improvement based on missing data imputation
Autorzy:
Jordanov, I.
Petrov, N.
Petrozziello, A.
Powiązania:
https://bibliotekanauki.pl/articles/91626.pdf
Data publikacji:
2018
Wydawca:
Społeczna Akademia Nauk w Łodzi. Polskie Towarzystwo Sieci Neuronowych
Tematy:
machine learning
missing data
model-based imputation
neural networks
random forests
support vector machine
radar signal classification
nauczanie maszynowe
brakujące dane
sieci neuronowe
maszyna wektorów nośnych
klasyfikacja sygnałów radarowych
Opis:
In this paper we investigate further and extend our previous work on radar signal identification and classification based on a data set which comprises continuous, discrete and categorical data that represent radar pulse train characteristics such as signal frequencies, pulse repetition, type of modulation, intervals, scan period, scanning type, etc. As the most of the real world datasets, it also contains high percentage of missing values and to deal with this problem we investigate three imputation techniques: Multiple Imputation (MI); K-Nearest Neighbour Imputation (KNNI); and Bagged Tree Imputation (BTI). We apply these methods to data samples with up to 60% missingness, this way doubling the number of instances with complete values in the resulting dataset. The imputation models performance is assessed with Wilcoxon’s test for statistical significance and Cohen’s effect size metrics. To solve the classification task, we employ three intelligent approaches: Neural Networks (NN); Support Vector Machines (SVM); and Random Forests (RF). Subsequently, we critically analyse which imputation method influences most the classifiers’ performance, using a multiclass classification accuracy metric, based on the area under the ROC curves. We consider two superclasses (‘military’ and ‘civil’), each containing several ‘subclasses’, and introduce and propose two new metrics: inner class accuracy (IA); and outer class accuracy (OA), in addition to the overall classification accuracy (OCA) metric. We conclude that they can be used as complementary to the OCA when choosing the best classifier for the problem at hand.
Źródło:
Journal of Artificial Intelligence and Soft Computing Research; 2018, 8, 1; 31-48
2083-2567
2449-6499
Pojawia się w:
Journal of Artificial Intelligence and Soft Computing Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Continuous solutions of iterative equations of infinite order
Autorzy:
Kapica, R.
Morawiec, J.
Powiązania:
https://bibliotekanauki.pl/articles/255177.pdf
Data publikacji:
2009
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
random-valued vector functions
sequences of iterates
iterative equations
continuous solutions
Opis:
Given a probability space (Ω, A, P) and a complete separable metric space X, we consider R continuous and bounded solutions φ: X → R of the equations φ (x) = ∫Ω φ(ƒ(x, ω)) P(dω) and φ(x) = 1 - ∫Ωφ(ƒ(x, ω)) P(dω), assuming that the given function ƒ : X x Ω → X is controlled by a random variable L: Ω → (0, ∞) with -∞ < ∫Ω log L (ω) P (dω) < 0. An application to a refinement type equation is also presented.
Źródło:
Opuscula Mathematica; 2009, 29, 2; 147-155
1232-9274
2300-6919
Pojawia się w:
Opuscula Mathematica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estymacja uogólnionej wariancji wybranych rozkładów wielowymiarowych
Estimation of Generalized Variance of Chosen Multivariate Distribution
Autorzy:
Witaszczyk, Anna
Powiązania:
https://bibliotekanauki.pl/articles/1827196.pdf
Data publikacji:
2009-06-30
Wydawca:
Główny Urząd Statystyczny
Tematy:
uogólniona wariancja
wektor losowy
macierz kowariancji
wyznacznik losowy
generalized variance
random vector
covariance matrix
random determinant
Opis:
Uogólniona wariancja, czyli wyznacznik macierzy kowariancji jest skalarną miarą rozrzutu rozkładów wielowymiarowych. Dokładny rozkład uogólnionej wariancji znany jest tylko dla wektorów losowych o wielowymiarowym rozkładzie normalnym. Dla wektorów losowych o dużych wymiarach przyjmuje on skomplikowaną postać, co stanowi utrudnienie w zastosowaniach praktycznych. W pracy przedstawiono tzw. G-estymator logarytmu uogólnionej wariancji otrzymany na podstawie twierdzeń granicznych dla wyznaczników losowych i jego własności na przykładach symulacyjnych dla kilku wybranych rozkładów wielowymiarowych.
Generalized variance i.e. the determinant of the covariance matrix is a scalar measure of multivariate distribution dispersion. The exact distribution of the generalized variance is known only for multivariate normal vectors. For random vectors in high dimensional spaces it has a complicated formula very troublesome to apply. An estimator of the logarithm of generalized variance derived with the help of limit theorems for random determinants was presented as well as its properties in examples of chosen simulation multivariate distributions.
Źródło:
Przegląd Statystyczny; 2009, 56, 2; 135-153
0033-2372
Pojawia się w:
Przegląd Statystyczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of the COVID-19 pandemic on the expression of emotions in social media
Autorzy:
Ghosh, Debabrata
Powiązania:
https://bibliotekanauki.pl/articles/2027766.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Ekonomiczny w Katowicach
Tematy:
Classification
COVID-19
Emotion
Emotion analysis
Naïve Bayes
Pandemic
Random Forest
Support Vector Machine
Opis:
In the age of social media, every second thousands of messages are exchanged. Analyzing those unstructured data to find out specific emotions is a challenging task. Analysis of emotions involves evaluation and classification of text into emotion classes such as Happy, Sad, Anger, Disgust, Fear, Surprise, as defined by emotion dimensional models which are described in the theory of psychology (www 1; Russell, 2005). The main goal of this paper is to cover the COVID-19 pandemic situation in India and its impact on human emotions. As people very often express their state of the mind through social media, analyzing and tracking their emotions can be very effective for government and local authorities to take required measures. We have analyzed different machine learning classification models, such as Naïve Bayes, Support Vector Machine, Random Forest Classifier, Decision Tree and Logistic Regression with 10-fold cross validation to find out top ML models for emotion classification. After tuning the Hyperparameter, we got Logistic regression as the best suited model with accuracy 77% with the given datasets. We worked on algorithm based supervised ML technique to get the expected result. Although multiple studies were conducted earlier along the same lines, none of them performed comparative study among different ML techniques or hyperparameter tuning to optimize the results. Besides, this study has been done on the dataset of the most recent COVID-19 pandemic situation, which is itself unique. We captured Twitter data for a duration of 45 days with hashtag #COVID19India OR #COVID19 and analyzed the data using Logistic Regression to find out how the emotion changed over time based on certain social factors
Źródło:
Multiple Criteria Decision Making; 2020, 15; 23-35
2084-1531
Pojawia się w:
Multiple Criteria Decision Making
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Method of optimal linear extrapolation of vector random sequences with full consideration of correlation connections for each component
Metod optimal'noy linejjnojj ehstrapoljacija vektornykh sluchajjnykh posledovatel'nostejj s polnym uchetom korreljacionnykh svjazejj dlja kazhdogo komponenta
Autorzy:
Atamanjuk, I.
Kondratenko, Y.
Powiązania:
https://bibliotekanauki.pl/articles/76650.pdf
Data publikacji:
2015
Wydawca:
Komisja Motoryzacji i Energetyki Rolnictwa
Tematy:
extrapolation
vector random sequence
algorithm
block diagram
canonical decomposition
Źródło:
Motrol. Motoryzacja i Energetyka Rolnictwa; 2015, 17, 2
1730-8658
Pojawia się w:
Motrol. Motoryzacja i Energetyka Rolnictwa
Dostawca treści:
Biblioteka Nauki
Artykuł

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