@article{U._U.A._2020, title={Assessment and Prediction of Repair and Maintenance Costs of Tractors in Northern Nigeria}, url={https://jurnalmekanikal.utm.my/index.php/jurnalmekanikal/article/view/396}, abstractNote={<p><em><span style="font-family: 'Times New Roman'; font-size: small;">Tractor has been identified as the central machine in the farm. The repair and maintenance (R&amp;M) costs of farm machineries including tractors have increasingly becomes difficult to estimate and evaluate. This study focuses on the assessment and prediction of farm machinery R&amp;M cost at the Tractor Owners and Hiring Facilities Association of Nigeria (TOHFAN). The purpose of this study is to develop a mathematical model that can predict and estimate the </span></em><em><span style="font-size: small;">R&amp;M</span></em><em><span style="font-size: small;">cost (Y) of tractors with their working hours (X) based on the available data at TOHFAN. Two brands of the tractor models widely used in the country were chosen, namely, Mahindra 6005 and John Deere 5065E. Data obtained from the study were subjected to a trend analysis, thereby generating five regression models: the Linear, Logarithmic, Polynomial, Power, and Exponential models. The results of the analysis show that the Polynomial model gives a better cost estimate with higher confidence level and less variation for Mahindra 6005, while the Linear model provides a better cost estimate for John Deere 5065E. It was also established that the </span></em><em><span style="font-size: small;">R&amp;M costs</span></em><em><span style="font-size: small;"> of both tractors increase with the increase in working hours, which can be used in management decisions and business development</span></em><em><span style="font-size: small;">.</span></em></p>}, number={43}, journal={Jurnal Mekanikal}, author={U., Dankyarana and U.A., Umar}, year={2020}, month={Oct.} }