<p>依据样本<img src="https://file.gaojiufeng.cn/learnAppQuestion/d5/94/d59451d3100b6919f2db9cac452e3cea.jpg" style="width: 100%;height: auto;">得到一元线性回归方程<img src="https://file.gaojiufeng.cn/learnAppQuestion/ab/cc/abccb9dee6ef838f662c81e39a45c07c.jpg" style="width: 100%;height: auto;"><img src="https://file.gaojiufeng.cn/learnAppQuestion/f1/4a/f14a1546b9c24f7787b04d8001fb8811.jpg" style="width: 100%;height: auto;">为样本均值，令<img src="https://file.gaojiufeng.cn/learnAppQuestion/83/31/8331672b6ca953e4e88d9c0f0659c2d0.jpg" style="width: 100%;height: auto;">2，<img src="https://file.gaojiufeng.cn/learnAppQuestion/2f/52/2f524ce4e8ba286ef8b58bee898fc263.jpg" style="width: 100%;height: auto;">，则回归常数<img src="https://file.gaojiufeng.cn/learnAppQuestion/1a/44/1a443a55de8ac34af4e7d3637e6dfd92.jpg" style="width: 100%;height: auto;">=_______