... Many researchers have studied the economic-inner relationship between Bitcoin and gold such as the conditional variance properties, hedging capabilities, etc. (Baur, Dimpfl, & Kuck, 2018;Long, Pei, Tian, & Lang, 2021;Wu, Tong, Yang, & Derbali, 2019;Ye, Sun, & Miao, 2020;Chkili, Ben Rejeb, & Arfaoui, 2021;Guesmi, Saadi, Abid, & Ftiti, 2019), and some of the researchers found that hedging strategies involving Bitcoin will reduce the portfolio's risk, as compared to the risk of the portfolio without Bitcoin (gold, oil, etc.) (Wu, Tong, Yang, & Derbali, 2019;Guesmi, Saadi, Abid, & Ftiti, 2019). This discovery gives us the confidence to find the best trading strategy of the portfolio made by Bitcoin and gold. ...