Chapter 4: Simple random sampling
Page 89, Table 4.4
use "a\:table44.dta", clear list
+------+
| col1 |
|------|
1. | 33.5 |
2. | 32 |
3. | 52 |
4. | 43 |
5. | 40 |
|------|
6. | 41 |
7. | 45 |
8. | 42.5 |
9. | 39 |
+------+
Page 89
tabstat col1, s(mean var)
variable | mean variance
-------------+--------------------
col1 | 40.88889 35.67361
----------------------------------
Figure 4.1, page 90
graph hbox col1, ytitle('Amount')
Page 102, Table 4.5
use "a:\table46.dta", clear rename col1 make rename col2 model rename col3 size rename col4 price rename col5 mpg rename col6 hp drop if size == . list
+----------------------------------------------------+
| make model size price mpg hp |
|----------------------------------------------------|
1. | Acura Integra 1 15.9 31 140 |
2. | Dodge Colt 1 9.2 33 92 |
3. | Honda Civic 1 12.1 46 102 |
4. | Hyundai Excel 1 8 33 81 |
5. | Mazda 323 1 8.3 37 82 |
|----------------------------------------------------|
6. | Mitsubishi Mirage 1 10.3 33 92 |
7. | Subaru Justy 1 8.4 37 73 |
8. | Suzuki Swift 1 8.6 43 70 |
9. | Toyota Tercel 1 9.8 37 82 |
10. | Volkswagen Fox 1 9.1 33 81 |
|----------------------------------------------------|
11. | Chevrolet Corsica 2 11.4 34 110 |
12. | Chrysler LeBaron 2 15.8 28 141 |
13. | Ford Tempo 2 11.3 27 96 |
14. | Mazda 626 2 16.5 34 164 |
15. | Subaru Lagacy 2 19.5 30 130 |
|----------------------------------------------------|
16. | BMW 535i 3 30 30 208 |
17. | Chevrolet Lumina 3 15.9 29 110 |
18. | Dodge Dynasty 3 15.6 27 100 |
19. | Ford Taurus 3 20.2 30 140 |
20. | Hyundai Sonata 3 13.9 27 128 |
|----------------------------------------------------|
21. | Lexus SC300 3 35.2 23 225 |
22. | Mitsubishi Diamante 3 26.1 24 202 |
23. | Nissan Maxima 3 21.5 26 160 |
24. | Pontiac Grand_Prix 3 18.5 27 200 |
25. | Toyota Camry 3 18.2 29 130 |
|----------------------------------------------------|
26. | Volvo 850 3 26.7 28 168 |
+----------------------------------------------------+
sort size by size: tabstat price mpg hp, s(n mean p50 sd semean)
_______________________________________________________________________________
-> size = 1
stats | price mpg hp
---------+------------------------------
N | 10 10 10
mean | 9.97 36.3 89.5
p50 | 9.15 35 82
sd | 2.408342 4.854551 20.07901
se(mean) | .7615846 1.535144 6.349541
----------------------------------------
_______________________________________________________________________________
-> size = 2
stats | price mpg hp
---------+------------------------------
N | 5 5 5
mean | 14.9 30.6 128.2
p50 | 15.8 30 130
sd | 3.52633 3.286335 26.53677
se(mean) | 1.577023 1.469694 11.8676
----------------------------------------
_______________________________________________________________________________
-> size = 3
stats | price mpg hp
---------+------------------------------
N | 11 11 11
mean | 21.98182 27.27273 161
p50 | 20.2 27 160
sd | 6.716371 2.284334 42.86024
se(mean) | 2.025062 .6887526 12.92285
----------------------------------------
Page 103, Figure 4.2
graph hbox mpg, by(size) ytitle("Highway mpg") ylabel(24(6)42)
