The Five-Number Summary

Maximum

Q3 (75th percentile)

Median (Q2, 50th percentile)

Q1 (25th percentile)

Minimum

Stem-and-Leaf Plots (Stemplots)

     8| 3
     7| 89
     7| 0122
     6| 001133555
     5| 77788
     5| 222
     4| 56699
     4| 022
     3| 799
     3| 355
     2| 69

Box-and-Whisker Plots (Boxplots)

Boxplot for multiple groups.

Stata Examples

use http://www.philender.com/courses/data/hsb2, clear
 
summarize write, detail

                        writing score
-------------------------------------------------------------
      Percentiles      Smallest
 1%           31             31
 5%         35.5             31
10%           39             31       Obs                 200
25%         45.5             31       Sum of Wgt.         200

50%           54                      Mean             52.775
                        Largest       Std. Dev.      9.478586
75%           60             67
90%           65             67       Variance       89.84359
95%           65             67       Skewness      -.4784158
99%           67             67       Kurtosis       2.238527
 
univar write
/* univar is available via the Internet, net search univar */

                                        -------------- Quantiles --------------
Variable       n     Mean     S.D.      Min      .25      Mdn      .75      Max
-------------------------------------------------------------------------------
   write     200    52.77     9.48    31.00    45.50    54.00    60.00    67.00
-------------------------------------------------------------------------------
 
stem write, lines(2)

Stem-and-leaf plot for write (writing score)

  3* | 11113333
  3. | 5566777899999
  4* | 0001111111111223444444444444
  4. | 56666666667799999999999
  5* | 00222222222222222344444444444444444
  5. | 5557777777777779999999999999999999999999
  6* | 000011112222222222222222223333
  6. | 55555555555555557777777
 
graph box write, fxsize(50)



 
table female, contents(freq mean write median write sd write)

----------+---------------------------------------------------
   female |       Freq.  mean(write)   med(write)    sd(write)
----------+---------------------------------------------------
     male |          91     50.12088           52     10.30516
   female |         109     54.99083           57     8.133716
----------+---------------------------------------------------
 
univar write, by(female)

-> female=male 
                                        -------------- Quantiles --------------
Variable       n     Mean     S.D.      Min      .25      Mdn      .75      Max
-------------------------------------------------------------------------------
   write      91    50.12    10.31    31.00    41.00    52.00    59.00    67.00
-------------------------------------------------------------------------------

-> female=female 
                                        -------------- Quantiles --------------
Variable       n     Mean     S.D.      Min      .25      Mdn      .75      Max
-------------------------------------------------------------------------------
   write     109    54.99     8.13    35.00    50.00    57.00    62.00    67.00
-------------------------------------------------------------------------------
 
graph box write, over(female)


 
Notched Boxplot



(Created in R)

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