first elementary regressions

例句：

1. 1.The first-level basic regression model is a simple yet effective tool for predicting customer behavior.
   第一级基本回归模型是一种简单而有效的工具，用于预测顾客行为。
2. 2.In the study of economics, first-level basic regressions are used to analyze the relationship between variables.
   在经济学研究中，第一级基本回归被用来分析变量之间的关系。
3. 3.The first-level basic regressions were developed by Dr. Smith to help students understand the concept of regression analysis.
   史密斯博士开发了第一级基本回归，帮助学生理解回归分析的概念。