一、基本概念1.统计检验的思考方法统计检验是根据一个样本(有些问题用几个样本) 来判断总体的情况。例6:某工程基础混凝土,在一定的配合比和工艺条件下,由长期连续试验得到的平均抗压强度μ_0=230公斤/厘米~2,标准离差σ_0=30公斤/厘米~2,后来部分地改变了生产工艺,从新工艺生产的混凝土中抽取25组试件,测得其平均强度(?)=245公斤/厘米~2(从经验知道,工艺改变后标准离差不变), I. Basic Concepts 1. Thinking Methods for Statistical Tests Statistical tests are based on a sample (some problems use several samples) to determine the overall situation. Example 6: The average compressive strength of a certain engineering foundation concrete under constant mixing ratio and process conditions, obtained from long-term continuous tests μ_0 = 230 kg/cm2, standard deviation σ_0 = 30 kg/cm2, later Partially changed the production process, 25 sets of specimens were taken from the concrete produced by the new process, and the average strength (?) = 245 kg/cm~2 was measured (from experience that the standard deviation after the process change is unchanged),