cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
Juhari
Contact Email
juhari@uin-malang.ac.id
Phone
+6281336397956
Journal Mail Official
cauchy@uin-malang.ac.id
Editorial Address
Jalan Gajayana 50 Malang, Jawa Timur, Indonesia 65144 Faximile (+62) 341 558933
Location
Kota malang,
Jawa timur
INDONESIA
CAUCHY: Jurnal Matematika Murni dan Aplikasi
Published by Universitas Islam Negeri Maulana Malik Ibrahim Malang
ISSN : 20860382     EISSN : 24773344     DOI : 10.18860
Core Subject : Education,
Mathematics
Jurnal CAUCHY secara berkala terbit dua (2) kali dalam setahun. Redaksi menerima tulisan ilmiah hasil penelitian, kajian kepustakaan, analisis dan pemecahan permasalahan di bidang Matematika (Aljabar, Analisis, Statistika, Komputasi, dan Terapan). Naskah yang diterima akan dikilas (review) oleh Mitra Bestari (reviewer) untuk dinilai substansi kelayakan naskah. Redaksi berhak mengedit naskah sejauh tidak mengubah substansi inti, hal ini dimaksudkan untuk keseragaman format dan gaya penulisan.
Arjuna Subject : -
Articles 438 Documents
 31   32   33   34   35 
Analyzing Household Expenditures with Generalized Random Forests Isnanda, Eriski; Notodiputro, Khairil Anwar; Sadik, Kusman
CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 10, No 1 (2025): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI
Publisher : Mathematics Department, Universitas Islam Negeri Maulana Malik Ibrahim Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/cauchy.v10i1.30104

Abstract

This study investigates the performance of Generalized Random Forest (GRF), which has been known to be useful in understanding heterogeneous treatment effects (HTE) and non-linear relationships in high-dimensional data. In this paper the performance of GRF was compared with Random Forest (RF), Generalized Linear Mixed Model (GLMM) as continuation of previous study conducted by Athey (2019). The data utilized in this study is from the National Socioeconomic Survey (SUSENAS) to predict household per capita expenditure in West Java, Indonesia. The models are evaluated based on their ability to handle outliers using Winsorization. The results show that RF performed the best, yielding the smallest MSE values, followed by GRF with reasonably good performance, and GLMM with the highest MSE, indicating its limitations in handling non-linear data patterns. These findings indicate that RF is the most accurate method for modeling per capita expenditure in West Java, with recommendations for further research to develop hybrid methods or use more specific random effects in GLMM
Simulation Study and Development of Semiparametric Multiresponse Multigroup Truncated Spline Regression for Rice Pest Control Azizah, Laila Nur; Fernandes, Adji Achmad Rinaldo; Wardhani, Ni Wayan Surya
CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 10, No 1 (2025): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI
Publisher : Mathematics Department, Universitas Islam Negeri Maulana Malik Ibrahim Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/cauchy.v10i1.29773

Abstract

Rice pest control is a critical challenge in the agricultural sector that requires a deep understanding of rice pest management. Regression analysis is a statistical method capable of describing and predicting cause-and-effect relationships between individuals. In real-life applications, not all relationships exhibit a known curve pattern, and non-identifiable curve forms are often observed. Additionally, a single cause may affect more than one outcome, and the outcomes themselves can have interrelationships. Such relationships can be approached through a multi-response semiparametric regression using a truncated spline multi-group model. This study aims to develop a multi-response semiparametric multi-group regression model using the truncated spline approach to understand the variables influencing rice pest control under light and dark conditions. This model is applied to secondary and simulated data with various scenarios to determine the best model. The study results indicate that the optimal model for secondary data is a semiparametric regression model with a linear order and a single knot point, achieving a determination coefficient of 89.17%. Simulation results show that the scenario 1 model (linear with a single knot point) produces a high determination coefficient. This multi-response regression model proves more optimal when error variance and multicollinearity levels are kept low to moderate.
Investment Portfolio Optimization of Mean-Entropic-VaR Model on the Top Ten Stocks from LQ45 in the Indonesian Capital Market Suhaimi, Nurnisaa binti Abdullah; Napitupulu, Herlina; Sukono, Sukono
CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 10, No 1 (2025): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI
Publisher : Mathematics Department, Universitas Islam Negeri Maulana Malik Ibrahim Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/cauchy.v10i1.30794

Abstract

In an investment portfolio, investors certainly choose a portfolio according to their preferences for return and risk. The problem is the allocation of investment weights in forming a portfolio, if the risk is in the form of Entropic-Value-at-Risk (EVaR). The purpose of this study is to determine the allocation of investment weights that maximize returns and minimize portfolio risk. The method used in this study is through investment portfolio optimization in the form of Mean-EVaR. The stages carried out are selecting the ten best stocks in the LQ45 index, estimating and testing the suitability of the return distribution, determining expectations, variance and covariance between stock returns, and optimizing the allocation of investment portfolio weights using the Mean-EVaR model. Based on the results of the analysis, it was obtained that the optimal portfolio weight allocation is 0.01073, 0.23284, 0.04617, 0.08052, 0.00470, 0.09021, 0.14669, 0.00427, 0.22672 and 0.15715, to be allocated successively to the stocks ACES, BBRI, EXCEL, ITMG, PTBA, ADRO, BBTN, GGRM, KLBF and AKRA. In this optimal portfolio, the average portfolio return is obtained at 0.00055 with an EVaR risk of 0.01632. It is hoped that the results of this study can provide a significant contribution to investors in making investments, especially in the ten stocks analyzed.
Analysis of Resolving Efficient Dominating Set and Its Application Scheme in Multi-Step Time Series Forecasting of pH and Soil Moisture in Horizontal Farming Dliou, Kamal; Aziza, Adinda Putri; Dafik, Dafik; Kristiana, Arika Indah; Retnowardani, Dwi Agustin
CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 10, No 1 (2025): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI
Publisher : Mathematics Department, Universitas Islam Negeri Maulana Malik Ibrahim Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/cauchy.v10i1.29960

Abstract

This research focuses on the analyzing the Resolving Efficient Dominating Set (REDS) and its application scheme in horizontal farming using the Spatial Temporal Graph Neural Network (STGNN). Soil moisture and pH are crucial factors that affect the growth and yield, as they directly impact productivity and plant health. In cases where soil moisture and pH are lacking, various types of companion planting need to be watered. In such planting systems, a central role is needed to monitor soil moisture and pH levels effectively. The placement of operators in this system requires the application of mathematical concepts, specifically graph theory. In this study, we explore graph theory, particularly the Resolving Efficient Dominating Set. This involves ensuring that each vertex  is dominated by exactly one vertex in D, with no adjacent with another vertex, and the representation of vertex  concerning  is not the same. To effectively address this issue, including soil moisture and pH data, is required to predict future soil moisture and pH values in companion farming. Spatial Temporal Graph Neural Network (STGNN) technique proves to be useful in solving the problem of soil moisture and pH by understanding and modeling multi-step time series data. This technique aids in effectively managing and optimizing horizontal farming.
Dynamical Analysis and Optimal Control of Breast Cancer Patient Model Muniroh, Kunnisai; Habibah, Ummu; Kusumawinahyu, Wuryansari Muharini
CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 10, No 1 (2025): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI
Publisher : Mathematics Department, Universitas Islam Negeri Maulana Malik Ibrahim Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/cauchy.v10i1.31514

Abstract

This research studied the dynamics model of breast cancer patients that was built as a dynamical system. The model had five compartments, including the subpopulations of stage 1 and 2 breast cancer patients, stage 3 cancer patients, stage 4 cancer patients, recovered individuals due to chemotherapy treatment, and patients who suffered cardiotoxicity. Equilibrium points and local stability were determined. The dynamical analysis resulted in one equilibrium point that exists and is stable under certain conditions. The model was constructed with the assumption that all patients undergo intensive chemotherapy treatment. This treatment caused side effects in the form of cardiotoxicity. Therefore, optimal control of additional treatment and ketogenic diet was applied. Additional treatment control is applied to prevent cardiotoxicity, while ketogenic diet control is used to reduce tumor cell growth. The aim of optimal control was to find out the treatment strategy that is effective in reducing cardiotoxicity and treatment costs. Numerical simulations were conducted to support the analysis results.
Modified WLS - Path Analysis In The Control Of Cattle Flies And Skin Defects Zuhdi, Muhammad Rizal; Fernandes, Adji; Wardhani, Ni Wayan Surya; Hamdan, Rosita
CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 10, No 1 (2025): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI
Publisher : Mathematics Department, Universitas Islam Negeri Maulana Malik Ibrahim Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/cauchy.v10i1.30118

Abstract

The cattle industry has an important role in the economy, especially in providing high-quality cowhide for various industries. However, fly infestation, especially from the Chloropidae and Muscidae families, causes many defects in cattle hides that negatively affect their economic value. This study aims to identify factors that influence the extent of defects in cattle hides, focusing on the role of temperature, humidity, and fly infestation. The study was conducted in a Malang cattle farming center by measuring temperature and humidity, catching flies, and calculating the defect area on cattle skin. Data were analyzed using path analysis using modified weighting with the help of R Studio software. The weights used were modified by including correlation in the weight matrix. The results showed that temperature had a significant effect on increasing the defect area in the cheek area of cattle, while humidity had no significant effect. In the abdominal area, neither temperature nor humidity affected the defect area. Infestations of Chloropidae and Muscidae flies were also shown to contribute to increased defect area in the cheek area, but not in the stomach. Preventive strategies for fly control and protection of cattle skin from temperature extremes are needed, especially in the cheek area.
Development of Semiparametric Smoothing Spline Path Analysis on Cashless Society Nurdin, Muhammad Rafi Hasan; Ullah, Muhammad Ohid; Fernandes, Adji Achmad Rinaldo; Sumarminingsih, Eni; Solimun, Solimun
CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 10, No 1 (2025): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI
Publisher : Mathematics Department, Universitas Islam Negeri Maulana Malik Ibrahim Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/cauchy.v10i1.29846

Abstract

Path analysis requires assumptions to be met, particularly the linearity assumption, which can be tested using the Ramsey Regression Specification Error Test (RESET). Parametric path analysis is appropriate when all variable relationships are linear. For entirely non-linear relationships, a nonparametric model can be used, while a semiparametric model applies if there is a mix of linear and non-linear relationships. One nonparametric method is spline smoothing, which requires determining the spline polynomial order in estimating the nonparametric path function. Determining the spline polynomial order is challenging because there is no standard test for it. This study thus develops a modified Ramsey RESET to identify the optimal spline smoothing order. The development involves modifying the second regression equation with a nonparametric spline smoothing regression of orders 2 to 5. The modified Ramsey RESET algorithm is applied to cashless data, and the results are used to estimate a multi-group semiparametric smoothing spline function with a dummy variable approach. This estimation yields a goodness of fit of 94.14%, indicating that Product Quality and the Moderating Effect of Cashless Usage Frequency can explain Cashless User Satisfaction and Cashless User Loyalty by 94.14%, with the remaining 5.86% explained by variables outside the research model
Mean-Variance Portfolio Optimization with Lot Size Constraints in Energy Stocks: A Monte CarloApproach Vimelia, Willen; Riaman, Riaman; Sukono, Sukono
CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 10, No 1 (2025): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI
Publisher : Mathematics Department, Universitas Islam Negeri Maulana Malik Ibrahim Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/cauchy.v10i1.32159

Abstract

Stock investment requires portfolio optimization strategies that maximize returns and consider risks and practical constraints, such as target lot sizes. These constraints are crucial to ensuring the realistic implementation of portfolios in compliance with market regulations, particularly in Indonesia, where 1 lot equals 100 shares. However, existing research on the Mean-Variance model and Monte Carlo simulation has rarely incorporated target lot constraints, limiting the applicability of these models in real-world scenarios. To bridge this gap, this study conducts a systematic literature review (SLR) on portfolio optimization in Indonesia's energy sector stocks, focusing on the Mean-Variance model, risk aversion, Monte Carlo simulation, and target lot constraints. The PRISMA framework guides this SLR, with bibliometric analysis performed using RStudio. A rigorous selection process from Scopus and ScienceDirect databases yielded 13 relevant articles for in-depth analysis creates a more practical and effective approach to portfolio management. This advancement enables investors to achieve balanced portfolios that are both theoretically robust and feasible in practice. The study contributes significantly to optimizing investment strategies for Indonesia’s energy sector and opens avenues for further research into practical portfolio optimization methods.
Development of Semiparametric Truncated Spline Logistic Path Analysis Rejeki, Sasi Wilujeng Sri; Solimun, Solimun; Nurjannah, Nurjannah; Yulianto, Shalsa Amalia; Ullah, Muhammad Ohid
CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 10, No 1 (2025): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI
Publisher : Mathematics Department, Universitas Islam Negeri Maulana Malik Ibrahim Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/cauchy.v10i1.29979

Abstract

Logistic path analysis extends logistic regression by incorporating intervening variables, addressing the limitations of linearity assumptions through nonparametric models like spline regression. However, this study develops a semiparametric truncated spline logistic path analysis to accommodate linear and nonlinear relationships, considering direct and indirect effects of intervening variables. The model is applied to analyze the impact of price volatility and human resource quality on farmer welfare, with farmer productivity as an intervening variable. It assumes a nonlinear relationship between price volatility and productivity/welfare, while other relationships are linear. This development was applied to secondary data collected through questionnaires from farmer group members in Bali Province, which were analyzed using a semiparametric truncated spline logistic path model. Optimal knots were determined using the lowest GCV value. The results show that the model effectively captures changes in data patterns, providing robust parameter estimates. Hypothesis testing highlights significant differences in the effectiveness of linear and nonlinear relationships. The use of truncated splines offers critical insights into variable interactions and enhances model reliability, making it a valuable tool for analyzing complex agricultural systems and informing policies to improve farmer welfare and productivity.
Zero Divisor Graph of Quotient Ring Musyarrofah, Ayunda Faizatul; Krisnawati, Vira Hari; Hidayat, Noor
CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 9, No 2 (2024): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI
Publisher : Mathematics Department, Universitas Islam Negeri Maulana Malik Ibrahim Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18860/ca.v9i2.29008

Abstract

Recently, a lot of research has been carried out regarding graphs built from algebraic structures, including ring structures. One important example of a graph constructed from a ring is the zero divisor graph. For a commutative ring R, the zero divisor graph Γ(R) is defined as a simple graph with vertices that are non-zero zero divisors of R, and two distinct vertices are adjacent if and only if the product of the vertices is equal to zero. In this paper, we investigate the zero divisor graph of the quotient ring ℤp[x]/⟨x5⟩ with prime p. More precisely, we characterize some graph properties, including the order, size, adjacency matrix, degree, distance, diameter, girth, clique number, and chromatic number of Γ(ℤp[x]/⟨x5⟩).

Page 33 of 44 | Total Record : 438

 31   32   33   34   35 

Filter by Year

2009 2026


Reset
Filter By Issues
All Issue Vol 11, No 1 (2026): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI Vol 10, No 2 (2025): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI Vol 10, No 1 (2025): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI Vol 9, No 2 (2024): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI Vol 9, No 1 (2024): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI Vol 8, No 2 (2023): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI Vol 7, No 4 (2023): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI Vol 7, No 2 (2022): CAUCHY: Jurnal Matematika Murni dan Aplikasi (May 2022) (Issue in Progress) Vol 7, No 3 (2022): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI Vol 7, No 2 (2022): CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 7, No 1 (2021): CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 6, No 4 (2021): CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 6, No 3 (2020): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI Vol 6, No 2 (2020): CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 6, No 1 (2019): CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 5, No 4 (2019): CAUCHY Vol 5, No 4 (2019): CAUCHY Vol 5, No 3 (2018): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI Vol 5, No 3 (2018): CAUCHY Vol 5, No 2 (2018): CAUCHY Vol 5, No 1 (2017): CAUCHY Vol 4, No 4 (2017): CAUCHY Vol 4, No 3 (2016): CAUCHY Vol 4, No 2 (2016): CAUCHY Vol 4, No 1 (2015): CAUCHY Vol 3, No 4 (2015): CAUCHY Vol 3, No 3 (2014): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI Vol 3, No 3 (2014): CAUCHY Vol 3, No 2 (2014): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI Vol 3, No 2 (2014): CAUCHY Vol 3, No 1 (2013): Cauchy Vol 3, No 1 (2013): CAUCHY Vol 2, No 4 (2013): CAUCHY Vol 2, No 3 (2012): CAUCHY Vol 2, No 2 (2012): CAUCHY Vol 2, No 1 (2011): CAUCHY Vol 1, No 4 (2011): CAUCHY Vol 1, No 2 (2010): CAUCHY Vol 1, No 1 (2009): CAUCHY More Issue