概率论与数理统计数据的简单处理.ppt

* * 9 * * * * * * * * * * * * * * * * * * 补充：EXCEL中茎叶图的作法： 例、某百货公司连续40天的商品销售额 （单位：万元）如下： 41 25 29 47 38 34 30 38 43 40 46 36 45 37 37 36 45 43 33 44 35 28 46 34 30 37 44 26 38 44 42 36 37 37 49 39 42 32 36 35 茎叶图作法： 1、排序 在常用工具栏里点“升序排列”对原始数据从小到大排序 2、提取“茎”和“叶”，点“插入” →“函数” →“文本” →“LEFT”和“RIGHT”，调用函数将每个数据分离成“茎”和“叶”两个部分, 3、制作“茎”和“叶”，根据“茎”的取值范围, 生成一列连续数据作为茎叶图的“茎”; 然后, 调用 “选择性粘贴”功能, 将原始数据中与“茎”对应的“叶”依次转置粘贴成茎叶图中的“叶”。（也可用“自动筛选”功能选出叶来） 4、计算“叶”的频数 ，点“插入” →“函数” →“统计” →“COUNTA”，调用计数函数算出茎叶图上每行的“叶”的数目，生成茎叶图。 茎叶图的生成全过程如下： * * 9 * * * * * * * * * * Shape Concerned with extent to which values are symmetrically distributed. Kurtosis The extent to which a distribution is peaked (flatter or taller). For example, a distribution could be more peaked than a normal distribution (still may be 慴ell-shaped). If values are negative, then distribution is less peaked than a normal distribution. Skew The extent to which a distribution is symmetric or has a tail. Values are 0 if normal distribution. If the values are negative, then negative or left-skewed. * * * * * * * * * * * * * * Shape Concerned with extent to which values are symmetrically distributed. Kurtosis The extent to which a distribution is peaked (flatter or taller). For example, a distribution could be more peaked than a normal distribution (still may be 慴ell-shaped). If values are negative, then distribution is less peaked than a normal distribution. Skew The extent to which a distribution is symmetric or has a tail. Values are 0 if normal distribution. If the values are negative, then negative or left-skewed. （2）峰度系数 (kurtosis coefficient) 1. 根据原始数据计算 2. 根据分组数据计算 2.4 分布偏态与峰态的测度 峰度系数的计算： 统计函数—KURT 偏态系数和峰度系数 (例题分析) 某电脑公司销售量偏态及峰度计算表 按销售量份组(台) 组中值(Mi) 频数 fi 140 ~ 150 150 ~ 160 160 ~ 170 170 ~ 180 180 ~190 190 ~200 200 ~210 210 ~220 220 ~ 230 230 ~ 240 145 155 165 175 185 195 205 215 225 235 4 9 16 27 20 17 10 8 4 5 -256000 -243000 -128000 -27000 0 17000 80000 216000 256000 625