Implementation of the C4.5 Decision Tree Algorithm Method for Selection of Facial Mask Skin Care Products

Facial treatment is a method for maintaining skin health and treating various facial skin problems. Facial masks for skincare are currently one of the most popular facial treatments. Many local and international cosmetic brands offer facial mask products in various variants, where each variant has its functions and benefits. Therefore, consumers should get advice from experts before selecting facial mask skincare suitable for their skin type. Hence, in a modern environment, it is necessary to create an expert system that can act as an expert and allow customers to conduct online consultations for the proper facial treatment. Various methods, such as the decision tree algorithm C4.5, can be applied to build an expert system for selecting facial masks for skin care. The C4.5 algorithm's decision tree method transforms existing data into a decision tree, then converted into a decision rule. Customer data was used in this study, with 220 customers used to build decision tree rules and 44 customer data used for accuracy testing. The result of testing data obtained an accuracy rate of 84.09%.