对同一维度的数据分析数据分布范围及分布趋势,要通过制作直方图和正态分布曲线图体现。
例如:已知所有员工的日收入,分析员工收入分布情况(51.7,50.6,57.9,56.9,56.7,56.7,55.3,56.1,53.7,54.5,56.9,51.9,52.1,55.1,54.9,54.7,55.3,55.3,54.5,54.9,54.5,55.3,54.9,54.3,53.7,53.5,53.7,53.1,54.5,53.1,53.9,53.5,53.3,53.9,53.5,53.5,52.5,53.3,53.5,53.3,53.7,53.1,54.5,53.9,56.7,54.5,54.3,55.1,54.1,54.5,53.9,53.1,53.3,55.3,55.7,56.1,54.7,53.1,53.3,52.7,53.1,52.9,53.1,54.3,53.1,52.7,53.1,53.3,53.1,53.3,53.1,53.3,55.1,54.7,54.9,54.3,53.9,53.7,53.9,53.5,54.5,54.3,55.5,55.7,55.5,54.9,55.3,55.5,53.7,54.1,53.9,55.7,55.9,53.7,53.5,53.1,52.3,52.7,52.9,53.3,53.9,52.7,53.5,53.1,52.7,51.9,52.5,53.9,54.5,55.7,55.3,54.9,53.1,52.9,54.1,53.3,54.7,53.9,54.3,54.1,53.7,53.3,52.7,52.9,52.5,53.9,53.5,54.1,54.1,54.7,54.9,54.9,54.1,53.3,52.9,53.7,53.9,54.3,54.1,54.5,54.7,54.9,52.1,52.9,53.5,52.7,53.1,53.1,53.5,52.9,52.9,53.1,53.3,52.7,53.5,53.9,54.9,55.1,54.3,55.1,54.3,54.3,53.9,54.5,54.5,54.3,55.3,54.5,54.9,53.5,52.1,55.3,55.7,55.7,55.5,54.5,57.7,54.7,53.7,53.1,53.7,55.9,56.1,53.9,53.7,53.3,53.9,53.9,54.5,54.7,56.1,55.7,53.1,53.7,53.5,53.9,53.9,53.5,53.3,53.1,52.5,55.9,55.7,54.1,54.3,54.1,54.1,54.5,54.5,55.1,53.1,53.3,54.1,54.3,53.9,54.1,54.7,54.7,53.7,53.1,53.3,52.7,53.5,52.9,53.7,56.5,56.1,55.7,55.5,56.9,57.7,56.5,55.7,54.1,54.7,55.7,55.5,53.1,52.7,53.1,53.3,53.5,54.3,54.1,54.5,54.7,55.7,55.5,54.1,54.3,54.7,53.1,53.3,53.1,52.7,53.1,53.7,53.1,54.7,54.5,55.1,54.7,54.5,56.1,55.7,53.3,52.5,53.7,54.1,53.3,52.1,52.3,53.1,53.3,53.5,53.3,53.1,52.7,53.1,55.7,55.1,54.3,53.7,53.1,52.9,53.1,52.7,52.5,53.1,53.5,53.1,53.3,54.1,55.1,54.9,56.1,55.7,56.5,54.7,53.7)
一、制作直方图
- 将数据输入到EXCEL同一列中(这里放入A列);
- 计算“最大值”、“最小值”、“极差”、“分组数”、“分组组距”;
最大值:max(A:A);(=57.9)
最小值:min(A:A);(=50.6)
极差:最大值-最小值;(=7.3)
分组数:roundup(sqrt(count(A;A)),0);(=18)/*count(A:A)计算A列包含数字的单元格个数,sqrt求平方根,roundup按指定位数对数据进行向上四舍五入*/;
分组组距:极差/分组数;(0.4)
- 数据分组:选一个比最小值小的一个恰当的值作为第一个组的起始坐标,然后依次加上“分组组距”,直到最后一个数据值比“最大值”大为止。
这里第一个组的起始坐标选为50.5,依次增加0.4,最后一组坐标为58.2,共计20组
- 统计频率:统计每个分组中所包含的数据的个数。
方法:采用FREQUENCY函数,以一列垂直数组返回一组数据的频率分布,
1、=frequency(原始数据的范围,直方图分组的数据源);
2、先选中将要统计直方图每个子组中数据数量的区域
3、再按“F2”健,进入到“编辑”状态
4、再同时按住“Ctrl”和“Shift”两个键,再按“回车Enter”键,最后三键同时松开.
- 制作直方图:选择频率数插入柱状图
- 修整柱形图:设置数据系列格式-调制无间距
二、制作正态分布图
- 获取正态分布概念密度:NORMDIST(作用:返回指定平均值和标准偏差的正态分布函数)
语法:
NORMDIST(x,mean,standard_dev,cumulative)
X 为需要计算其分布的数值;(以每一个分组边界值为“X”,依次往下拉)
Mean 分布的算术平均值;(Mean=AVERAGE(A:A)(数据算术平均))【这里为54.09】
Standard_dev 分布的标准偏差;(Standard_dev=STDEV.S(A:A)(数据的标准方差)【1.15】
Cumulative=false(概率密度函数)
Cumulative 为一逻辑值,指明函数的形式。如果 cumulative 为 TRUE,函数 NORMDIST 返回累计分布函数;如果为 FALSE,返回概率密度函数。
- 在直方图中增加正态分布曲线图:设置曲线图,选择次坐标轴