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Rainfall Forecasting Using an Adaptive Neuro-Fuzzy Inference System with a Grid Partitioning Approach to Mitigating Flood Disasters 利用网格划分方法的自适应神经模糊推理系统进行降雨预报,以减轻洪水灾害
Pub Date : 2024-04-02 DOI: 10.31764/jtam.v8i2.20385
Fatkhurokhman Fauzi, Relly Erlinda, Prizka Rismawati Arum
Hydrometeorological disasters are one of the disasters that often occur in big cities like Semarang. Hydrometeorological disasters that often occur are floods caused by high-intensity rainfall in the area. Early mitigation needs to be done by knowing about future rain. Rainfall data in Semarang City fluctuates, so the Adaptive Neuro-Fuzzy Inference System (ANFIS) method approach is very appropriate. This research will use the Grid Partitioning (GP) approach to produce more accurate forecasting. The data used in this research is daily rainfall observation data from the Meteorology Climatology Geophysics Agency (BMKG). The membership functions used are Gaussian and Generalized Bell. The two membership functions will be compared based on the RMSE and MAPE values to get the best one. The data used in this research is daily rainfall data. Rainfall in Semarang City every month experiences anomalies, which can result in flood disasters. The ANFIS-GP method with a Gaussian membership function is the best, with an RMSE value of 0.0898 and a MAPE of 5.2911. Based on the forecast results for the next thirty days, a rainfall anomaly of 102.53 mm on the thirtieth day could cause a flood disaster. 
水文气象灾害是三宝垄等大城市经常发生的灾害之一。经常发生的水文气象灾害是该地区高强度降雨引发的洪水。需要通过了解未来的降雨情况来及早减轻灾害。三宝垄市的降雨数据起伏不定,因此自适应神经模糊推理系统(ANFIS)方法非常适合。本研究将使用网格划分(GP)方法来进行更准确的预测。本研究使用的数据是气象气候地球物理局(BMKG)的每日降雨量观测数据。使用的成员函数是高斯和广义贝尔。将根据 RMSE 和 MAPE 值对这两个成员函数进行比较,以选出最佳成员函数。本研究使用的数据是每日降雨量数据。三宝垄市每月的降雨量都会出现异常,从而导致洪水灾害。采用高斯成员函数的 ANFIS-GP 方法效果最佳,其 RMSE 值为 0.0898,MAPE 为 5.2911。根据未来 30 天的预测结果,第 30 天的降雨量异常值为 102.53 毫米,可能会导致洪水灾害。
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引用次数: 0
Projection of PT Aneka Tambang Tbk Share Risk Value Based on Backpropagation Artificial Neural Network Forecasting Result 基于反向传播人工神经网络预测结果的 PT Aneka Tambang Tbk 股票风险价值预测
Pub Date : 2024-04-02 DOI: 10.31764/jtam.v8i2.20267
M. A. Haris, L. Setyaningsih, Fatkhurokhman Fauzi, Saeful Amri
PT Aneka Tambang Tbk (ANTAM) received an award as the most sought-after stock issuer in Indonesia in 2016. That stock continued to attract investors in 2022 due to a 105% increase in net profit and a 19% increase in sales from the previous year. Despite the upward trend, investors still had doubts due to the fluctuating movement of ANTAM's stock prices. Therefore, forecasting was needed to determine the future movement of stock prices. The Backpropagation Neural Network method had good capabilities for fluctuating data types. However, this method has the disadvantage of a lengthy iteration process. To handle this limitation, The Nguyen-Widrow weighted setting was applied to address this constraint. The expected Shortfall (ES) method used the forecasting results to measure investment risk. This research uses ANTAM stock closing price data from May 2, 2018, to May 31, 2023. Based on the analysis results, the best architecture was obtained with a configuration of 5-11-1, using Nguyen-Widrow weight initialization and a combination of a learning rate of 0.5 and momentum of 0.9. This architecture yielded a prediction error based on the Mean Absolute Percentage Error (MAPE) of 1.9947%. Risk measurement with the ES method based on the prediction for the next 60 periods showed that at a 95% confidence level, the risk value was 0.002181; at a 90% confidence level, it was 0.002165; at an 85% confidence level, it was 0.002148, and at an 80% confidence level, it was 0.002132.
PT Aneka Tambang Tbk(ANTAM)在2016年获得了印尼最受欢迎股票发行商奖。2022 年,由于净利润比上一年增长了 105%,销售额增长了 19%,该股票继续吸引着投资者。尽管呈上升趋势,但由于 ANTAM 股票价格的波动,投资者仍心存疑虑。因此,需要通过预测来确定股价的未来走势。反向传播神经网络方法对波动数据类型有很好的处理能力。但是,这种方法的缺点是迭代过程较长。为了解决这一限制,我们采用了 Nguyen-Widrow 加权设置法。预期缺口(ES)法使用预测结果来衡量投资风险。本研究使用了 2018 年 5 月 2 日至 2023 年 5 月 31 日的 ANTAM 股票收盘价数据。根据分析结果,采用 5-11-1 的配置,使用 Nguyen-Widrow 权重初始化以及 0.5 的学习率和 0.9 的动量组合,获得了最佳架构。根据平均绝对百分比误差 (MAPE) 计算,该架构的预测误差为 1.9947%。根据 ES 方法对未来 60 期的预测进行的风险测量显示,在 95% 的置信度下,风险值为 0.002181;在 90% 的置信度下,风险值为 0.002165;在 85% 的置信度下,风险值为 0.002148;在 80% 的置信度下,风险值为 0.002132。
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引用次数: 0
Identifying Factors Affecting Waste Generation in West Java in 2021 Using Spatial Regression 利用空间回归确定影响 2021 年西爪哇废物产生的因素
Pub Date : 2024-04-02 DOI: 10.31764/jtam.v8i2.19664
Anik Djuraidah, Akbar Rizki, Tony Alfan
Responsible consumption and production is the 12th of the seventeen SDGs which is difficult for developing countries to achieve due to high waste production. Indonesia is the second largest producer of food waste in the world. Garbage is solid waste generated from community activities. Population density is an indicator to estimate the amount of waste generated in an area. The choice of West Java Province as the research area is based on the fact that this Province has the second highest population density in Indonesia. This study aimed to determine the predictors/factors that influence waste production in the districts/cities of West Java Province. The data used in this study are total waste as a response variable and GRDP (gross domestic product), total spending per capita, average length of schooling, literacy rate, number of MSMEs (micro, small, and medium enterprises), and several recreational and tourism places, the number of people's markets, and the number of restaurants as predictors. The methods used in this research are spatial autoregressive regression/SAR, spatial Lag-X/SLX, and spatial Durbin/SDM. The results of this study show that the SAR is the best model with the lowest BIC (74.442) and pseudo-R-squared (0.7934). Factors that significantly affect total waste production are literacy levels, the number of MSMEs, the number of traditional markets, and the number of recreational and tourist places. 
负责任的消费和生产是十七项可持续发展目标中的第 12 项目标,由于废物产量高,发展中国家很难实现这一目标。印度尼西亚是世界上第二大食物垃圾生产国。垃圾是社区活动产生的固体废物。人口密度是估算一个地区垃圾产生量的指标。之所以选择西爪哇省作为研究地区,是因为该省是印尼人口密度第二高的省份。本研究旨在确定影响西爪哇省各县/市废物产生量的预测因素/因子。本研究使用的数据包括作为响应变量的垃圾总量,以及作为预测变量的国内生产总值(GRDP)、人均总支出、平均受教育年限、识字率、微型和中小型企业(MSME)数量、若干休闲和旅游场所、人民市场数量以及餐馆数量。本研究采用的方法有空间自回归/SAR、空间 Lag-X/SLX、空间 Durbin/SDM。研究结果表明,SAR 是 BIC(74.442)和伪 R 方(0.7934)最低的最佳模型。对废物总产量有重大影响的因素包括识字水平、中小微企业数量、传统市场数量以及休闲和旅游场所数量。
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引用次数: 0
Development of a Desmos-Assisted Planar Analytic Geometry Textbook to Support High Order Thinking Skills 开发 Desmos 辅助平面解析几何教科书以支持高阶思维技能
Pub Date : 2024-04-02 DOI: 10.31764/jtam.v8i2.20775
Yunika Lestaria Ningsih, D. Octaria, T. D. Nopriyanti, Jumroh Jumroh
The study focuses on improving higher-order thinking skills (HOTS) in mathematics students using a Desmos-assisted planar analytic geometry course. Analytic geometry, which is essential for understanding geometric properties using analytic methods, requires students to develop problem-solving, analysis, assessment, and creativity abilities. However, current educational practices fall short of acquiring these abilities due to insufficient instructional techniques, textbooks, and a lack of integration with information and communication technologies. To address these shortcomings, the study proposes a Desmos-assisted textbook meant to increase students' HOTS through the use of interactive Desmos platform tools such as graphic depiction, experimentation, simulation, and collaborative learning. The textbook development followed the PLOMP model, which included preliminary research, prototyping, and assessment phases, ensuring the textbook's validity and practicality through reiterated evaluations. The findings show that the textbook is highly valid and practical for instructional purposes, improving students' knowledge of mathematical concepts and ability to engage in HOTS processes. Despite some difficulties with HOTS-related practice questions, generally student feedback was positive, emphasizing the textbook's function in supporting a deeper understanding of analytic geometry and encouraging problem-solving skills. The study indicates that integrating technology such as Desmos into mathematics education can greatly contribute to the development of students' HOTS, and recommends its use in teaching techniques as well as additional research on its implementation in educational contexts.
本研究的重点是利用 Desmos 辅助平面解析几何课程提高数学学生的高阶思维能力(HOTS)。解析几何是利用解析方法理解几何性质的关键,要求学生培养解决问题、分析、评估和创造的能力。然而,由于教学技巧、教科书不足,以及缺乏与信息和通信技术的整合,目前的教育实践无法让学生获得这些能力。针对这些不足,本研究提出了 Desmos 辅助教科书,旨在通过使用图形描述、实验、模拟和协作学习等交互式 Desmos 平台工具,提高学生的 HOTS 能力。教科书的开发遵循 PLOMP 模式,包括前期研究、原型设计和评估阶段,通过反复评估确保教科书的有效性和实用性。研究结果表明,该教科书在教学方面具有很高的有效性和实用性,提高了学生对数学概念的认识和参与 HOTS 过程的能力。尽管在处理与 HOTS 相关的练习题时遇到了一些困难,但学生的反馈普遍是积极的,强调了教科书在支持学生加深对解析几何的理解和鼓励学生提高解决问题的能力方面的作用。研究表明,将 Desmos 等技术整合到数学教育中能极大地促进学生 HOTS 的发展,并建议在教学技术中使用该技术,以及对其在教育环境中的实施进行更多的研究。
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引用次数: 0
Exploring Multivariate Copula Models and Fuzzy Interest Rates in Assessing Family Annuity Products 在评估家庭年金产品中探索多元 Copula 模型和模糊利率
Pub Date : 2024-04-02 DOI: 10.31764/jtam.v8i2.17467
Kurnia Novita Sari, Ady Febrisutisyanto, Randi Deautama, Nursiti Azirah, Pida Mahani
This research explores the development of a reversionary annuity product transformed into a family annuity covering three individuals: husband, wife, and children. The innovative design of this product considers the sequencing of annuity payments post-participant's demise, aiming to mitigate the risk of parents' death impacting their children. Recognizing the inadequacy of assuming independence among individuals in premium calculations, the study employs a multivariate Archimedean Copula model to account for interdependence. The primary objective is to compute the survival single-life function for each individual taken from TMI IV 2009. Then the copula model is implemented with Clayton and Frank copulas at varying Kendall’s tau values (0.25, 0.5, and 0.75). Meanwhile, the interest rates are modeled using the BI-7-day (reverse) rate with a Triangular Fuzzy α-cut. The findings reveal that increasing Kendall’s tau values lead to higher pure premiums, and notably, the Frank Copula model yields higher premium values than the Clayton Copula model. This research contributes valuable insights into the actuarial assessment of family annuity products, shedding light on the significance of considering dependencies among individuals for more accurate premium calculations.
本研究探讨了将复归年金产品转化为家庭年金的发展情况,该家庭年金覆盖三个人:丈夫、妻子和子女。该产品的创新设计考虑了参与人死亡后的年金支付顺序,旨在降低父母死亡影响子女的风险。本研究认识到在计算保费时假设个人之间的独立性是不够的,因此采用了一个多变量阿基米德 Copula 模型来考虑相互依赖性。主要目标是计算 2009 年 TMI IV 中每个人的生存单寿命函数。然后,在不同的 Kendall's tau 值(0.25、0.5 和 0.75)下使用 Clayton 和 Frank copulas 实现 copula 模型。同时,使用三角模糊 α 切分的 BI-7 天(反向)利率对利率进行建模。研究结果表明,Kendall's tau 值的增加会导致纯保费的增加,值得注意的是,Frank Copula 模型比 Clayton Copula 模型产生更高的保费值。这项研究为家庭年金产品的精算评估提供了宝贵的见解,阐明了考虑个人之间的依赖关系对于更准确地计算保费的重要性。
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引用次数: 0
An Inclusive Distance Irregularity Strength of n-ary Tree nary 树的包容性距离不规则性强度
Pub Date : 2024-04-02 DOI: 10.31764/jtam.v8i2.20549
K. Wijaya, Safira Nur Aulia, I. Halikin, Kusbudiono Kusbudiono
An inclusive distance vertex irregular labelling of a simple graph G is a function of the vertex set of  to positive integer set such that the sum of its vertex label and the labels of all vertices adjacent to the vertex are distinct. The minimum of maximum label of the vertices is said to be inclusive distance irregularity strength of G, denoted by dis(G). The purpose of this research is showing that dis(T_{n,2})= (n^2+2)/2 where T_{n,2} is a complete n-ary tree to level two.
简单图 G 的包容距离顶点不规则标注是指顶点集为正整数集的函数,使得其顶点标注与该顶点相邻的所有顶点标注之和是不同的。顶点标签的最小值和最大值称为 G 的包容性距离不规则强度,用 dis(G) 表示。本研究的目的是证明 dis(T_{n,2})= (n^2+2)/2 其中 T_{n,2} 是一棵二级的完整 nary 树。
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引用次数: 0
Robust Optimization of Vaccine Distribution Problem with Demand Uncertainty 具有需求不确定性的疫苗配送问题的稳健优化
Pub Date : 2024-04-02 DOI: 10.31764/jtam.v8i2.20035
Faiqul Fikri, B. P. Silalahi, J. Jaharuddin
This study proposes a multi objective optimization model for vaccine distribution problems using the Maximum Covering Location Problem (MCLP) model. The objective function of the MCLP model in this study is to maximize the fulfillment of vaccine demand for each priority group at each demand point. In practice, the MCLP model requires data on the amount of demand at each demand point, which in reality can be influenced by many factors so that the value is uncertain. This problem makes the optimization model to be uncertain linear problem (ULP). The robust optimization approach converts ULP into a single deterministic problem called Robust Counterpart (RC) by assuming the demand quantity parameter in the constraint function is in the set of uncertainty boxes, so that a robust counterpart to the model is obtained. Numerical simulations are carried out using available data. It is found that the optimal value in the robust counterpart model is not better than the deterministic model but is more resistant to changes in parameter values. This causes the robust counterpart model to be more reliable in overcoming uncertain vaccine distribution problems in real life. This research is limited to solving the problem of vaccine distribution at a certain time and only assumes that the uncertainty of the number of requests is within a specified range so that it can be developed by assuming that the number of demand is dynamic.
本研究利用最大覆盖位置问题(MCLP)模型,为疫苗分配问题提出了一个多目标优化模型。本研究中 MCLP 模型的目标函数是最大限度地满足每个需求点上每个优先群体的疫苗需求。在实践中,MCLP 模型需要每个需求点的需求量数据,而现实中的需求量会受到很多因素的影响,因此其值是不确定的。这个问题使得优化模型成为不确定线性问题(ULP)。稳健优化方法通过假定约束函数中的需求量参数位于不确定性箱集中,将 ULP 转化为一个单一的确定性问题,称为稳健对应问题(RC),从而得到模型的稳健对应问题。利用现有数据进行了数值模拟。结果发现,稳健对应模型的最优值并不比确定性模型好,但更能抵御参数值的变化。这使得鲁棒对应模型在克服现实生活中不确定的疫苗分布问题时更加可靠。本研究仅限于解决某一时间的疫苗分配问题,并且仅假设需求数量的不确定性在指定范围内,因此可以通过假设需求数量是动态的来进行开发。
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引用次数: 0
Gender Disparities Impact on Pre-Service Teachers' Attitudes in Mathematics and Statistics Education 性别差异对职前教师数学和统计教育态度的影响
Pub Date : 2024-04-02 DOI: 10.31764/jtam.v8i2.20396
Loso Judijanto, Jitu Halomoan Lumbantoruan
The research investigates the impact of gender disparities on prospective teachers' attitudes towards statistics in mathematics education. The problem is a lack of understanding of how gender influences attitudes towards statistics. This research aims to explore differences in attitudes towards statistics based on gender and identify factors that influence these attitudes. The urgency lies in the importance of better understanding how gender can influence attitudes toward statistics among prospective teachers. This research method uses the Attitudes towards Statistics Survey (SATS-36) survey which was completed by 355 prospective teachers from 7 TTCs who were randomly selected. Data was collected through an online survey and analyzed using an independent T-test to compare the attitudes of prospective teachers based on gender. The results show that prospective teachers have a positive attitude towards statistics and gender has a significant influence on attitudes towards statistics. A significant difference was found in attitudes towards statistics between male and female teacher candidates, with men tending to have more positive attitudes. The conclusion is that gender plays an important role in shaping prospective teachers' attitudes towards statistics. The implication is that special attention is needed to pay attention to gender factors in developing mathematics education curricula to increase interest and understanding of statistics among prospective teachers.
这项研究调查了性别差异对未来教师在数学教育中对统计学态度的影响。问题在于人们对性别如何影响对统计学的态度缺乏了解。本研究旨在探讨基于性别的统计态度差异,并找出影响这些态度的因素。其紧迫性在于,必须更好地了解性别如何影响未来教师对统计学的态度。本研究采用统计态度调查(SATS-36)的方法,从 7 所培训中心随机抽取了 355 名准教师填写调查问卷。数据通过在线调查收集,并使用独立 T 检验对准教师的性别态度进行比较分析。结果显示,准教师对统计学持积极态度,性别对统计学态度有显著影响。结果发现,男女教师候选人对统计学的态度存在明显差异,男性倾向于持更积极的态度。结论是,性别在塑造未来教师对统计的态度方面起着重要作用。这意味着在开发数学教育课程时需要特别关注性别因素,以提高未来教师对统计学的兴趣和理解。
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引用次数: 0
Control Chart for Correcting the ARIMA Time Series Model of GDP Growth Cases 修正国内生产总值增长 ARIMA 时间序列模型案例的控制图
Pub Date : 2024-01-19 DOI: 10.31764/jtam.v8i1.19612
Nurfitri Imro'ah, N. M. Huda, Dewi Setyo Utami, Tarisa Umairah, Nani Fitria Arini
The essential prerequisite for attending the G20 conference is a country's GDP because G20 members can significantly boost the economy and preserve the nation's financial stability. Time series data can be thought of as a country's Gross Domestic Product (GDP) at a particular point in time. In this research, the GDP numbers from five Southeast Asian nations that are attending the G20 fulfilling are used. The total was 47 observations made yearly, which extended from 1975 to 2001. A time series analysis was performed on the data gathered. The correctness of time series models is also evaluated using control charts based on this research. The control chart is constructed using the time series model's residuals as observations. After applying the IMR control chart for verification, the results revealed that the residuals, specifically the models for GDP in Malaysia, Singapore, and Thailand, are out of control. The white noise assumption is fulfilled by the time series model obtained for Brunei and Indonesia's GDP, but the residuals are out of control. Whether controlled residuals are used depends on the accuracy with which the time series model predicts the future. If the amount of residuals is under control, then the time series model produced is accurate and good enough for prediction. After using the IMR control chart to verify the residuals, the results indicate that the residuals, namely the models for GDP in Malaysia, Singapore, and Thailand, are not under control. The assumption of white noise is proved correct by the time series model obtained for the GDP of Brunei Darussalam and Indonesia. With that being said, the residuals are entirely out of control. The model must improve its ability to forecast various future periods. It is a consequence of the unmanageable residuals that the model contains. Even if the best available model has been obtained based on the criteria that have been defined, it is anticipated that the research findings will improve the theories that have previously been developed and raise knowledge regarding the usefulness of testing the time series model. In addition to all of that, it is intended that the research will produce a summary of cases of an increase in GDP from five Southeast Asian countries participating in the G20 conference. 
参加 G20 会议的基本前提是一个国家的国内生产总值,因为 G20 成员国可以极大地促进经济发展,维护国家的金融稳定。时间序列数据可视为一个国家在特定时间点的国内生产总值(GDP)。本研究使用了参加 G20 会议的五个东南亚国家的国内生产总值数据。从 1975 年到 2001 年,每年共进行 47 次观测。对收集到的数据进行了时间序列分析。在此研究基础上,还使用控制图评估了时间序列模型的正确性。控制图是以时间序列模型的残差作为观测值绘制的。在应用 IMR 控制图进行验证后,结果显示残差,特别是马来西亚、新加坡和泰国的国内生产总值模型失控。文莱和印度尼西亚国内生产总值的时间序列模型符合白噪声假设,但残差失控。是否使用受控残差取决于时间序列模型预测未来的准确性。如果残差量在可控范围内,那么所生成的时间序列模型就足够准确和适合预测。在使用 IMR 控制图验证残差后,结果表明马来西亚、新加坡和泰国的国内生产总值模型的残差没有得到控制。文莱达鲁萨兰国和印度尼西亚国内生产总值的时间序列模型证明白噪声假设是正确的。尽管如此,残差完全失控。该模型必须提高对未来各个时期的预测能力。这是模型残差无法控制的结果。即使根据已确定的标准获得了现有的最佳模型,预计研究结果也将改进以前提出的理论,并提高有关测试时间序列模型有用性的知识。除此以外,本研究还打算对参加 20 国集团会议的五个东南亚国家的国内生产总值增长案例进行总结。
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引用次数: 0
ARIMA Time Series Modeling with the Addition of Intervention and Outlier Factors on Inflation Rate in Indonesia 添加干预和异常值因素的印度尼西亚通货膨胀率 ARIMA 时间序列模型
Pub Date : 2024-01-19 DOI: 10.31764/jtam.v8i1.17487
Dewi Setyo Utami, N. M. Huda, Nurfitri Imro'ah
Extreme events in a time series model can be detected when the precise timing of the event, known as the intervention, is known. When the exact timing of an event is unknown, it is referred to as an outlier.  If these factors are neglected, the model's accuracy will be affected. To overcome this situation, it is possible to add the intervention or outlier factor into the time series model. This study proposes the combination of intervention and outlier analysis in time series models, especially ARIMA. It is intended to minimize the residuals and increase the accuracy of the model so that it is suitable for forecasting. Using the data of inflation rate in Indonesia, the conflict between Russia and Ukraine was used as an intervention factor in this case. Pre-intervention data (before February 2022) is used to construct the ARIMA model (1st  model). After that, the modeling process continued by adding the intervention factor to the ARIMA model. The effect caused by the intervention allows an outlier to appear, so the process is continued by adding the outlier factor, called an additive outlier, into the model before (2nd model). The MAPE for the first and second models is 7.96% and 7.57%, respectively. The finding of this research shows that the ARIMA model with intervention and outlier factors, named as the 2nd model, is the best model. This study shows that combining the intervention and outlier factors into ARIMA model can improve the accuracy. The forecasting of the inflation rate in Indonesia for one period ahead in 2023 is in the range of 2.06%.
时间序列模型中的极端事件可以在事件发生的精确时间(即干预)已知的情况下被检测出来。当事件的确切时间未知时,它被称为离群值。 如果忽略这些因素,模型的准确性就会受到影响。为了克服这种情况,可以在时间序列模型中加入干预或离群因子。本研究提出在时间序列模型中结合干预和离群值分析,尤其是 ARIMA 模型。其目的是尽量减少残差,提高模型的准确性,使其适用于预测。利用印度尼西亚的通货膨胀率数据,将俄罗斯和乌克兰之间的冲突作为干预因素。干预前的数据(2022 年 2 月之前)用于构建 ARIMA 模型(第一模型)。之后,在 ARIMA 模型中加入干预因素,继续建模过程。干预所产生的影响使得离群值出现,因此在之前的模型中加入离群值因子(称为加性离群值),继续建模过程(第 2 个模型)。第一个和第二个模型的 MAPE 分别为 7.96% 和 7.57%。研究结果表明,带有干预因素和离群因子的 ARIMA 模型(称为第 2 个模型)是最佳模型。这项研究表明,在 ARIMA 模型中加入干预因素和异常值因素可以提高模型的准确性。印度尼西亚 2023 年通货膨胀率的预测范围为 2.06%。
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引用次数: 0
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