1. Statistics
note

2. Software can’t think for you
•

3. Pie Charts
• 片slice大，说明频率frequency高

4. Bar Charts

5. Histogram
• 跟bar charts不一样：无间隙

7. cumulative frequency 积累频率
• 不停累积数值

8. 趋势

9. Mean 平均值
•

10. • outliers 异常值

11. Finding the median 找中位线
• 方法：排序，找中间值

12. mean and median exercise
• If you had to pick one age to represent this
class, what would it be? Why?
– 两个不同的年龄段，不能只用一个数值来表示
• What if you could pick two ages instead?
Which two ages would you pick, and why?
– 2和32

13. mode
• 频率最高的叫mode