Jurnal Varian https://journal.universitasbumigora.ac.id/index.php/Varian <p style="text-align: justify;"><strong>Jurnal Varian</strong>&nbsp;(<strong>e-ISSN. 2581-2017</strong>) is one of the scientific journals at Universitas Bumigora (former STMIK Bumigora Mataram)&nbsp;. This journal aims to provide a forum or means of publication for lecturers, researchers and practitioners both in the internal and external environment of Universitas Bumigora. This journal is published 2 (two) times a year in the Even (April) and Odd (October) periods. The Jurnal Varian focuses on publicizing Statistics,&nbsp;Mathematics and their aplication.&nbsp;For more information, contact the admin via email: <strong>varian@universitasbumigora.ac.id</strong></p> <p style="text-align: justify;">&nbsp;</p> <p style="text-align: justify;">&nbsp;</p> <p style="text-align: justify;">&nbsp;</p> en-US sitisorayaburhan@universitasbumigora.ac.id (Siti Soraya) sitisorayaburhan@universitasbumigora.ac.id (Siti Soraya) Mon, 01 Jul 2024 00:00:00 +0800 OJS 3.1.0.1 http://blogs.law.harvard.edu/tech/rss 60 Estimating and Forecasting Jakarta Composite Index in Pandemic Era Using ARIMA-GARCH Model https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/2103 <p>Many industries have suffered financial losses as a result of the COVID-19 epidemic. The stock market's movement has been impacted by this circumstance. Due to the influence of some people, a large number of individuals with limited trading knowledge are attempting to participate in the stock market. Market volatility should be understandable in order to gain profit instead of having losses. Therefore, it's essential to comprehend the market of the future through analysis of the data. The purpose of this study is to use ARIMA-GARCH to predict the Indonesian stock market price during. The period covered by the dataset is January 2020–December 2022. The training data indicates that ARIMA (2,1,2) is the best model for ARIMA. The results showed that data residual fitted by ARIMA (2,1,2)-GARCH (1,2) exhibits heteroscedasticity, according to the residual analysis. The MAPE score is 2%, which is relatively small. It means that ARIMA (2,1,2)-GARCH (1,2) is good enough for forecasting the Jakarta Composite Index.</p> Agus Sofian Eka Hidayat, Gilang Primajati ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/2103 Sun, 30 Jun 2024 23:00:34 +0800 Naive Bayes Algorithm with Feature Selection Using Particle Swarm Optimization https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/2409 <p>The COVID-19 vaccine in Indonesia has led to the emergence of public opinion which is conveyed on social media such as Twitter. One of the analyses that can be done to produce various information from public opinion is sentiment analysis. Sentiment analysis is used to determine whether an opinion tends to be positive or negative. This study aims to classify the public opinion of the COVID-19 vaccine in Indonesia with sentiment analysis and to visualize the location of the sentiment of the COVID-19 vaccine tweet data in Indonesia. To achieve this aim, the Naïve Bayes algorithm with Particle Swarm Optimization (PSO) feature selection was used. This study uses opinions into positive and negative class sentiments towards 2,547 tweets related to the COVID-19 vaccine in Indonesia from January to June 2021. The results show that the distribution of positive and negative class sentiments is 2,328 and 219, respectively. In addition, the positive sentiment for the COVID-19 vaccine was dominated by people on the island of Java based on a random number matrix initialized by the PSO method. The classification of public opinion on Twitter media provides accurate and optimal performance results using a combination of the Naïve Bayes algorithm with PSO feature selection. The results of the combination of these methods have accuracy and F1 score values of 91.28% and 95.38%, respectively. The visualization of geo-spatial mapping showed that positive sentiments related to the COVID-19 vaccine exist in almost all regions in Indonesia but are dominated by the Jabodetabek area.</p> Sri Astuti Thamrin, Iwan Kurniawan, Siswanto Siswanto ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/2409 Sun, 30 Jun 2024 23:04:34 +0800 Natural Disaster Mapping on Java Island Using Biplot Analysis https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/2634 <p>Indonesia is located in the ring of fire region. This condition causes Indonesia to have the potential to experience various disasters, such as volcano eruptions. In addition, rapid population growth has led to rampant land conversions that cause floods, landslides, tornadoes, droughts, and forest fires. The research aims to map natural disasters in Indonesia, especially Java Island to find out the provinces and their natural disasters tendency using Biplot analysis. Based on the results, Central Java, East Java, and West Java have a tendency to have floods and landslides. East Java tends to undergo earthquakes and Central Java has the potential to experience volcano eruptions. Through the natural disasters mapping, the government, especially the BMKG, will be able to find various solutions to overcome the natural disasters that have great potential to occur in provinces in Indonesia, especially Java Island as the manifestation toward SDGs Target 2030.</p> Pressylia Aluisina Putri Widyangga, M. Fariz Fadillah Mardianto, Firda Aulia Pratiwi, Andi Vania Ghalliyah Putrie, Putu Eka Andriani, Dita Amelia, Deshinta Arrova Dewi ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/2634 Sun, 30 Jun 2024 23:23:51 +0800 Stunting Prevalence Modeling Using Nonparametric Regression of Quadratic Splines https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/2916 <p>The nonparametric regression approach is used when the shape of the regression curve between the response variable and the predictor variable is assumed to be of unknown shape. The advantages of nonparametric regression have high flexibility. A nonparametric regression approach that is often used is truncated spline which has an excellent ability to handle data whose behavior changes at certain sub-sub intervals. The purpose of this study is to obtain the best model of multivariable nonparametric regression with linear and quadratic truncated spline approaches using the Generalized Cross Validation (GCV) and Unbiased Risk (UBR) methods and to find out the factors that influence the prevalence of stunting in Indonesia in 2021. The data used were the prevalence of stunting as a response variable and the predictor variable used was the percentage of infants receiving exclusive breastfeeding for 6 months, the percentage of households that have proper sanitation, the percentage of toddlers who get Early Initiation of Breastfeeding (IMD), the percentage of poor people, and the percentage of pregnant women at risk of SEZ. The results showed that the best quadratic truncated spline nonparametric regression model in modeling stunting prevalence was quadraic truncated spline using the GCV method with three knot points. This model has a minimum GCV value of 7.29 with an MSE value of 1.82 and a <em>R<sup>2</sup></em> value of 94.07%.</p> Tutik Handayani, Sifriyani Sifriyani, Andrea Tri Rian Dani ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/2916 Sun, 30 Jun 2024 23:34:42 +0800 A Regression Model of Public Interest for COVID-19 Vaccination in Welcoming Events in the Mandalika Circuit Area in Central Lombok Regency https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/3130 <table> <tbody> <tr> <td width="741"> <p>The lack of a threshold value for herd immunity against COVID-19 ahead of the MotoGP 2022 Event in&nbsp;the Mandalika Circuit Area, Central Lombok Regency is the reason for the author to conduct this research. The objectives of this research are 1) to make a mathematical model of the interest of the people of Central Lombok Regency in the Covid-19 vaccination in welcoming the 2022 MotoGP Event and 2) to determine the &nbsp;influence of &nbsp;MotoGP Event 2022 and other factors on the interest of the people of Central Lombok Regency in carrying out the COVID-19 vaccination. This research is a type of quantitative descriptive research. &nbsp;The independent variables in this study are the variables of ease of getting the Covid-19 vaccination (X1), the efficacy of the COVID-19 vaccination (X2), trust in the government (X3), and the 2022 MotoGP event (X4), while the dependent variable is the variable of interest in covid-19 vaccination (Y). &nbsp;To achieve the objectives of this study, the authors collected data through a questionnaire that was distributed to 332 respondents, they’re people who received the full vaccine aged 12-70 years. The questionnaire was tested for validity and reliability. Data must first be transformed into interval data using the Method of Successive Interval (MSI) then&nbsp;analyzed using multiple linear regression with classical assumptions including normality, multicolllinearity and heteroskedasticity. The results showed that the 2022 MotoGP event did not have a significant effect on the interest of the people of central Lombok Regency to take part in the COVID-19 vaccination. The biggest factor that influences is the factor of people's trust in the government.</p> <p>&nbsp;</p> </td> </tr> </tbody> </table> Elok Faiqotul Himmah, Riana Riana ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/3130 Sun, 30 Jun 2024 23:49:49 +0800 Rainfall Forecasting at Six Surabaya Observation Post using ARIMAX and Support Vector Regression (SVR) https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/3202 <p>There is a seasonal element every year, with the dry season often lasting from May to October and the rainy season lasting from November to April. However, climate change causes the changing of the rainy and dry seasons to be erratic, so it is necessary to anticipate weather conditions. Prediction of rainfall is used to see natural conditions in the future with time series modeling. The rainfall modeling method at the six Surabaya observation posts used is the Autoregressive Integrated Moving Average with exogenous variables (ARIMAX) and Support Vector Regression. The exogenous variable used is the captured seasonal pattern of rainfall. The SVR model uses input lags from the ARIMAX model and parameter tuning uses the Kernel Radial Based Function. Selection of the best model uses the minimum RMSE value. The results showed that the average occurrence of rain at the six rainfall observation posts occurred in January, February, March, April, November and December. The ARIMAX method in this study is well used to predict rainfall in Gubeng and rainfall in Wonorejo. The SVR input lag ARIMAX method is good for predicting rainfall for Keputih, Kedung Cowek, Wonokromo and Gunung Sari. Nonparametric methods are better used to forecast rainfall data because they are able to capture data patterns with greater volatility than parametric methods, one of which is the SVR method.</p> Regita Putri Permata, Rifdatun Ni'mah; Andrea Tri Rian Dani ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/3202 Sun, 30 Jun 2024 00:00:00 +0800 Classification Classification of Criminal Events in Indonesia based on Biplot Analysis https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/3795 <p><span style="vertical-align: inherit;"><span style="vertical-align: inherit;">Kriminalitas merupakan suatu perilaku yang melanggar hukum dan aturan dalam masyarakat. </span><span style="vertical-align: inherit;">Penelitian ini dilakukan untuk menganalisis data biplot jumlah kejahatan di berbagai provinsi di Indonesia. </span><span style="vertical-align: inherit;">Biplot merupakan analisis yang berguna untuk menafsirkan hubungan antara variabel dan objek dalam bentuk grafik tunggal. </span><span style="vertical-align: inherit;">Sumber data dalam penelitian ini adalah data sekunder yang berasal dari website Badan Pusat Statistik yang berjudul “Statistik Kriminal 2022”. </span><span style="vertical-align: inherit;">34 kepolisian daerah yang mewakili setiap provinsi di Indonesia menjadi objek pengamatan dan 9 klasifikasi kejahatan menjadi variabel. </span><span style="vertical-align: inherit;">Metode penelitian ini menggunakan analisis biplot dengan bantuan fiton. </span><span style="vertical-align: inherit;">Dari nilai Dekomposisi Nilai Singular, keragaman data yang dapat dijelaskan sebesar 73,714%. </span><span style="vertical-align: inherit;">Pada grafik analisis biplot hubungan antar observasi diperoleh bahwa observasi atau objek polda dari setiap provinsi tersebar terpusat pada satu kuadran. </span><span style="vertical-align: inherit;">Hubungan antar variabel yang paling tinggi adalah korelasi antara variabel kejahatan narkotika dengan kejahatan yang berkaitan dengan penggelapan, penipuan, dan korupsi, sedangkan hubungan yang paling rendah adalah korelasi antara kejahatan narkotika dengan kejahatan terhadap ketertiban umum. </span><span style="vertical-align: inherit;">Dalam hubungan observasi dengan variabel diperoleh 4 kelompok. </span><span style="vertical-align: inherit;">Keberagaman variabel yang paling tinggi terletak pada kejahatan terhadap kebebasan masyarakat, sedangkan keberagaman variabel yang paling rendah terletak pada kejahatan terhadap kesusilaan.</span></span></p> Doni Muhammad Fauzi, Sanda Insania Dewanty, Farah Fauziah Putri, Alya Rahma Inneztiana, M. Fariz Fadillah Mardianto, Dita Amelia, Elly Ana ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/3795 Sun, 30 Jun 2024 23:55:21 +0800 CLUSTERING OF PROVINCE IN INDONESIA BASED ON EDUCATION INDICATORS USING K-MEDOIDS https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/3205 <table width="674"> <tbody> <tr> <td width="495"> <p>Data mining is searching for interesting patterns or information by selecting data using specific techniques or methods. One method that can be used in data mining is K-Medoids. K-Medoids is a method used to group objects into a cluster. This research aimed to obtain the optimal number of clusters using the K-Medoids method based on Davies-Bouldin Index (DBI) validity on education indicators data by province in Indonesia in 2021. The results showed that the optimal number of clusters using the K-Medoids method based on DBI validity is 5 clusters. Cluster 1 consists of 1 province with a higher average dropout rate, average length of schooling, and well-owned classrooms compared to other clusters. Cluster 2 consists of 15 provinces with an average proportion of school libraries lower than Clusters 3 and 4 and higher than Clusters 1 and 5. Cluster 3 consists of 9 provinces with an average proportion of school libraries, proportions of school laboratories, net enrollment rates, and higher school enrollment rates than other clusters. Cluster 4 consists of 8 provinces with a higher average enrollment rate than the other clusters. Cluster 5 consists of 1 province with a higher average repetition rate and student-per-teacher ratio than other clusters.</p> </td> </tr> </tbody> </table> Annisa Zuhri Apridayanti ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/3205 Sun, 30 Jun 2024 23:58:54 +0800 MAPPING OF VILLAGE POPULATION PROFILE WITH SCHISTOSOMIASIS CASES IN POSO DISTRICT USING THE METHOD CLUSTERING LARGE APPLICATION (CLARA) https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/3423 <p><em>Schistosomiasis</em> is a tropical disease caused by <em>Schistosoma mansoni</em> (intestinal schistosomiasis) and Schistosoma haematobium (urogenital schistosomiasis). <em>Schistosomiasis</em> in Indonesia is endemic to Central Sulawesi and is commonly found in the Napu Valley and Bada Valley areas, which are administratively included in Poso District and Sigi District. One approach to obtain information on <em>schistosomiasis</em> endemic areas is by mapping the population profile of villages with <em>schistosomiasis</em> cases. This mapping is intended to provide an overview of the social and demographic conditions of villages with <em>schistosomiasis</em> cases. One of the many analysis methods that can be used is cluster analysis. Cluster analysis is a method for grouping data based on the extent of their similarities. Data with similar characteristics will be grouped together, while data with different characteristics will be placed in different groups. Among several types of methods in cluster analysis is Clustering Large Application (CLARA). CLARA is a clustering method which is more robust to unusual data and can be applied to handle large volumes of data. The results of this study are obtained two optimum clusters, each possessing distinct characteristics as determined by <em>Schistosomiasis</em> cases indicators. Cluster 1 with low <em>schistosomiasis</em> cases and cluster 2 with high <em>schistosomiasis</em> cases<em>.</em></p> <p>&nbsp;</p> Mohammad Fajri ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/3423 Mon, 01 Jul 2024 00:00:43 +0800 Comparison of Naïve Bayes Classification Methods Without and With Kernel Density Estimation https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/3199 <p>Halal certification is important to give confidence to Muslim consumers around the world regarding the halalness of products. The Halal Product Assurance Organizing Body (BPJPH) is the official auditor in Indonesia that is responsible for the halal certification process. This study aims to address the need for verification and validation of data for halal certification applications in Indonesia by using the data science approach and machine learning technology. In this study, the Naïve Bayes classification method was used to optimize the data verification and validation process. However, this method needs to be improved by applying optimization methods such as Kernel Density Estimation (KDE) to improve classification results. The results showed that the Naïve Bayes classification method with KDE optimization produced better performance than the Naïve Bayes method without optimization. The performance of the Naïve Bayes classification model without optimization achieves 87.6% Accuracy, 85.4% Recall, 88.8% Precision, and 87.1% F<sub>measure</sub>. Meanwhile, the Naïve Bayes classification model with KDE optimization achieves 97.5% Accuracy, 95.9% Recall, 98.9% Precision, and 97.8% F<sub>measure</sub>. Thus, it can be concluded that the Naïve Bayes classification algorithm with KDE optimization results in a performance increase of 9.9% compared to the Naïve Bayes method without optimization. This research has important implications in handling complex and non-normally distributed data and providing solutions for BPJPH in the process of verifying halal certification.</p> Agus Hermawan, Siswanto Siswanto, Andi Kresna Jaya ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://journal.universitasbumigora.ac.id/index.php/Varian/article/view/3199 Mon, 01 Jul 2024 00:01:37 +0800