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The examples presented in Chapter 1 involve several different datasets that appear more than once in different parts of the chapter. This web page follows each dataset throughout the whole chapter.Newcomb's 66 measurements of the passage time of light
Table 1.1, page 8.
use http://www.ats.ucla.edu/stat/stata/examples/mm/chap01/ta01_001, clear
list
time
1. 28
2. 26
3. 33
4. 24
5. 34
[data omitted]
62. 27
63. 28
64. 29
65. 16
66. 23
Figure 1.5, page 17.
histogram time, bin(24) freq ylabel(0(5)30) xlabel(-60(20)60)
Figure 1.6, page 19.
generate order = _n graph twoway scatter time order, ylabel(-60(20)60) xlabel(0(10)70)
Babe Ruth home run data
Example 1.4, page 10.
use http://www.ats.ucla.edu/stat/stata/examples/mm/chap01/ex01_037, clear
drop if year < 1920
drop if year > 1934
list
year hrs
1. 1920 54
2. 1921 59
3. 1922 35
4. 1923 41
5. 1924 46
6. 1925 25
7. 1926 47
8. 1927 60
9. 1928 54
10. 1929 46
11. 1930 49
12. 1931 46
13. 1932 41
14. 1933 34
15. 1934 22
Figure 1.2c, page 11.
stem hrs, round(1) lines(1) Stem-and-leaf plot for hrs hrs rounded to integers 2* | 25 3* | 45 4* | 1166679 5* | 449 6* | 0
Example 1.12, page 41.
summarize hrs
Variable | Obs Mean Std. Dev. Min Max
---------+-----------------------------------------------------
hrs | 15 43.93333 11.24701 22 60
Example 1.13, page 43. The median is the same as the 50th percentile which is displayed as 50% in Stata.
summarize hrs, detail
hrs
-------------------------------------------------------------
Percentiles Smallest
1% 22 22
5% 22 25
10% 25 34 Obs 15
25% 35 35 Sum of Wgt. 15
50% 46 Mean 43.93333
Largest Std. Dev. 11.24701
75% 54 54
90% 59 54 Variance 126.4952
95% 60 59 Skewness -.4827278
99% 60 60 Kurtosis 2.466472
Spending by 50 supermarket shoppers
Example 1.5, page 12.
use http://www.ats.ucla.edu/stat/stata/examples/mm/chap01/eg01_005, clear
list
amount
1. 3.11
2. 8.88
3. 9.26
4. 10.81
5. 12.69
[data omitted]
46. 70.32
47. 82.7
48. 85.76
49. 86.37
50. 93.34
Figure 1.3a, page 12.
stem amount, round(1) Stem-and-leaf plot for amount amount rounded to integers 0* | 399 1* | 1345677889 2* | 000123455668888 3* | 25699 4* | 1345579 5* | 0359 6* | 1 7* | 0 8* | 366 9* | 3
Figure 1.3b, page 12.
stem amount, round(1) lines(2) Stem-and-leaf plot for amount amount rounded to integers 0* | 3 0. | 99 1* | 134 1. | 5677889 2* | 0001234 2. | 55668888 3* | 2 3. | 5699 4* | 134 4. | 5579 5* | 03 5. | 59 6* | 1 6. | 7* | 0 7. | 8* | 3 8. | 66 9* | 3
Example 1.15, page 45 and Five-Number Summary, page 48. This analysis uses data rounded to whole numbers using the round function in Stata. Note Q1 is given as 25% and Q3 as 75%.
generate ramount = round(amount,1)
summarize ramount, detail
ramount
-------------------------------------------------------------
Percentiles Smallest
1% 3 3
5% 9 9
10% 13.5 9 Obs 50
25% 19 11 Sum of Wgt. 50
50% 28 Mean 34.68
Largest Std. Dev. 21.68272
75% 45 83
90% 65.5 86 Variance 470.1404
95% 86 86 Skewness 1.066941
99% 93 93 Kurtosis 3.511037
Figure 1.14, page 46. This analysis is on the unrounded data. The univar command is an ado which was down loaded from Stata. It can be found in Stata Technical Bulletin 51.
univar amount, detail
-------------- Quantiles --------------
Variable n Mean S.D. Min .25 Mdn .75 Max
-------------------------------------------------------------------------------
amount 50 34.70 21.70 3.11 19.27 27.85 45.40 93.34
-------------------------------------------------------------------------------
Figure 1.15, page 49.
graph box amount, ylabel(0(20)100)
Calories and sodium in three types of hot dogs
Table 1.8, page 40.
use http://www.ats.ucla.edu/stat/stata/examples/mm/chap01/ta01_008,clear
list
beef_cal beef_sod meat_cal meat_sod poultry_ poultry1
1. 186 495 173 458 129 430
2. 181 477 191 506 132 375
3. 176 425 182 473 102 396
4. 149 322 190 545 106 383
5. 184 482 172 496 94 387
6. 190 587 147 360 102 542
7. 158 370 146 387 87 359
8. 139 322 139 386 99 357
9. 175 479 175 507 170 528
10. 148 375 136 393 113 513
11. 152 330 179 405 135 426
12. 111 300 153 372 142 513
13. 141 386 107 144 86 358
14. 153 401 195 511 143 581
15. 190 645 135 405 152 588
16. 157 440 140 428 146 522
17. 131 317 138 339 144 545
18. 149 319 . . . .
19. 135 298 . . . .
20. 132 253 . . . .
Figure 1.16, page 49.
graph box beef_cal meat_cal poultry_, ylabel(80(20)200)
Example 1.17, page 50
univar beef_cal meat_cal poultry_
-------------- Quantiles --------------
Variable n Mean S.D. Min .25 Mdn .75 Max
-------------------------------------------------------------------------------
beef_cal 20 156.85 22.64 111.00 140.00 152.50 178.50 190.00
meat_cal 17 158.71 25.24 107.00 139.00 153.00 179.00 195.00
poultry_ 17 122.47 25.48 86.00 102.00 129.00 143.00 170.00
-------------------------------------------------------------------------------
Stemplot, page 50
stem meat_cal Stem-and-leaf plot for meat_cal 10* | 7 11* | 12* | 13* | 5689 14* | 067 15* | 3 16* | 17* | 2359 18* | 2 19* | 015
Example 1.23, page 74.
The zcalc command can be downloaded from UCLA ATS from within Stata (see How can I use the findit command to search for programs and get additional help? for more information about using findit).
zcalc 68 64.5 2.5
z-score for sample observations
(X - m) (68 - 64.5)
z = --------- = ------------------ = 1.40
s 2.5
Example 1.25, pages 76-77.
zcalc 240 170 30
z-score for sample observations
(X - m) (240 - 170)
z = --------- = ------------------ = 2.33
s 30
Figure 1.30, page 82.
use http://www.ats.ucla.edu/stat/stata/examples/mm/chap01/ta01_001, clear qnorm time, ylabel(-40(20)40)
Figure 1.31, page 82.
keep if time > 0 qnorm time, ylabel(10(10)40)
Figure 1.32, page 83.
use http://www.ats.ucla.edu/stat/stata/examples/mm/chap01/eg01_005, clear qnorm amount, ylabel(0(10)100)
Education data for 78 seventh-grade students.
Figure 1.33, page 83.
use http://www.ats.ucla.edu/stat/stata/examples/mm/chap01/ta01_006, clear qnorm col3, ylabel(60(20)140)
Guinea pig survival data
Figure 1.34, page 84.
use http://ats.ucla.edu/stat/stata/examples/mm/chap01/ta01_005, clear histogram survival, bin(12) xlabel(0(100)600) kdensity
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