Results are general statements that interpret data. Data are facts, often numbers that are used to support results.

Review the pertinent literature; Present the research question(s); State briefly the method of investigation.

a mini version, a condensed summary of your paper that stands on its own.

加权线性回归是什么、它与线性回归的差别，以及参数求解；加权线性回归应该如何有效地加权？如何确保权重的正确性？实现独立同分布确保R包中的 `lm()`有效加权。