Adji Fernandes
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Comparison of Parameter Estimator Efficiency Levels of Path Analysis with Bootstrap and Jack Knife (Delete-5) Resampling Methods on Simulation Data Adji Fernandes
Jurnal Matematika, Statistika dan Komputasi Vol. 16 No. 3 (2020): JMSK, MAY, 2020
Publisher : Department of Mathematics, Hasanuddin University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (436.245 KB) | DOI: 10.20956/jmsk.v16i3.9723

Abstract

In practice, the assumptions of normality are often not met, this causes the estimation of the resulting parameters to be less efficient. Problems with the assumption that normality is not met can be overcome by resampling. The use of resampling allows data to be applied free from distribution assumptions. In this study, a simulation study was carried out by applying bootstrap resampling and jackknife resampling (delete-5) on path analysis assuming that the normality of the alignment was not met and the resampling amount set at 1000 with the degree of closeness between variables consisting of low closeness, medium closeness, high closeness and closeness level representing the level low to high closeness. Based on the simulation results, the resampling 1000 magnitude is able to overcome the problem of the assumptions of unmet normality. In addition, a comparison between bootstrap and jackknife resampling for conditions of side normality assumptions is not fulfilled and the closeness of the relationship between low, medium, high and closeness variables representing low to high closeness levels, the estimation results of path analysis parameters obtained by resampling jackknife are more efficient than resampling bootstrap.
Modified WLS - Path Analysis In The Control Of Cattle Flies And Skin Defects Muhammad Rizal Zuhdi; Adji Fernandes; Ni Wayan Surya Wardhani; Rosita Hamdan
CAUCHY: Jurnal Matematika Murni dan Aplikasi Vol 10, No 1 (2025): CAUCHY: JURNAL MATEMATIKA MURNI DAN APLIKASI
Publisher : Mathematics Department, Maulana Malik Ibrahim State Islamic University of 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.