2.1.1简单随机抽样...ppt

文档介绍：第二章统计 简单随机抽样 (抽签法与随机数表法) Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. 问题提出 ,时刻都在和数据打交道,例如,产品的合格率,农作物的产量,商品的销售量, ,如何从总体中抽取具有代表性的样本,是我们需要研究的课题. Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. 2、要判断一锅汤的味道需要把整锅汤都喝完吗?应该怎样判断? 3、要判断一批炸药是否合格,要将整批炸药全部试放吗? 4 、要想知道自己头发的韧度,需要将头发全部采集下来进行实验吗? Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. 案例阅读: 在1936 年美国总统选举前, 一份颇有名气的杂志的工作人员对兰顿和罗斯福两位候选人做了一次民意测验. ,兰顿当选的可能性大( 57% ),但实际选举结果正好相反,最后罗斯福当选( 62% ).你认为预测结果出错的原因是什么? Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. 预****课本 56-57 页,回答下面问题: 1、简单随机抽样的含义是什么? 2、简单随机抽样的特点是什么? 3、简单随机抽样的方法有哪两种? 4、这两种抽样方法有什么优点和缺点? Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. 一般地,设一个总体有 N个个体, 从中逐个不放回地抽取 n个个体作为样本( n≤N), 如果每次抽取时总体内的各个个体被抽到的机会都相等, 则这种抽样方法叫做简单随机抽样. 1、简单随机抽样的含义: Evaluation only. Evaluation only. Created with Client Profile . Created with Client Profile . Copyright 2004-2011 Aspose Pty Ltd. Copyright 2004-2011 Aspose Pty Ltd. 知识探究(一):简单随机抽样