The Airline Cost Data: First Difference or Fixed Effects
/*--------------------------------------------------------------
SAS Sample Library
Name: panex02.sas
Description: Example program from SAS/ETS User's Guide,
The PANEL Procedure
Title: The Airline Cost Data: First Difference or Fixed Effects
Product: SAS/ETS
Keys: panel data
PROC: PANEL
Notes:
--------------------------------------------------------------*/
data Airline;
input Obs AirlineID T C Q PF LF;
Year = T + 1969;
lC = log(C);
lQ = log(Q);
lPF = log(PF);
label lC = "Log Transformation of Costs";
label lQ = "Log Transformation of Quantity";
label lPF = "Log Transformation of Price of Fuel";
label LF = "Load Factor (utilization index)";
datalines;
1 1 1 1140640 0.95276 106650 0.53449
2 1 2 1215690 0.98676 110307 0.53233
3 1 3 1309570 1.09198 110574 0.54774
4 1 4 1511530 1.17578 121974 0.54085
5 1 5 1676730 1.16017 196606 0.59117
6 1 6 1823740 1.17376 265609 0.57542
7 1 7 2022890 1.29051 263451 0.59450
8 1 8 2314760 1.39067 316411 0.59741
9 1 9 2639160 1.61273 384110 0.63852
10 1 10 3247620 1.82544 569251 0.67629
11 1 11 3787750 1.54604 871636 0.60574
12 1 12 3867750 1.52790 997239 0.61436
13 1 13 3996020 1.66020 938002 0.63337
14 1 14 4282880 1.82231 859572 0.65012
15 1 15 4748320 1.93646 823411 0.62560
16 2 1 569292 0.52064 103795 0.49085
17 2 2 640614 0.53463 111477 0.47345
18 2 3 777655 0.65519 118664 0.50301
19 2 4 999294 0.79158 114797 0.51250
20 2 5 1203970 0.84295 215322 0.56678
21 2 6 1358100 0.85289 281704 0.55813
22 2 7 1501350 0.92284 304818 0.55880
23 2 8 1709270 1.00000 348609 0.57207
24 2 9 2025400 1.19845 374579 0.62476
25 2 10 2548370 1.34067 544109 0.62871
26 2 11 3137740 1.32624 853356 0.58915
27 2 12 3557700 1.24852 1003200 0.53261
28 2 13 3717740 1.25432 941977 0.52665
29 2 14 3962370 1.37177 856533 0.54016
30 2 15 4209390 1.38974 821361 0.52878
31 3 1 286298 0.26242 118788 0.52433
32 3 2 309290 0.26643 123798 0.53719
33 3 3 342056 0.30604 122882 0.58212
34 3 4 374595 0.32559 131274 0.57949
35 3 5 450037 0.34571 222037 0.60659
36 3 6 510412 0.36752 278721 0.60727
37 3 7 575347 0.40994 306564 0.58243
38 3 8 669331 0.44802 356073 0.57397
39 3 9 783799 0.53960 378311 0.65426
40 3 10 913883 0.53938 555267 0.63106
41 3 11 1041520 0.46797 850322 0.56924
42 3 12 1125800 0.45054 1015610 0.58968
43 3 13 1096070 0.46879 954508 0.58795
44 3 14 1198930 0.49440 886999 0.56539
45 3 15 1170470 0.49332 844079 0.57708
46 4 1 145167 0.08639 114987 0.43207
47 4 2 170192 0.09674 120501 0.43967
48 4 3 247506 0.14150 121908 0.48893
49 4 4 309391 0.16972 127220 0.48418
50 4 5 354338 0.17381 209405 0.52993
51 4 6 373941 0.16427 263148 0.53272
52 4 7 420915 0.17091 316724 0.54907
53 4 8 474017 0.17784 363598 0.55714
54 4 9 532590 0.19225 389436 0.61138
55 4 10 676771 0.24247 547376 0.64532
56 4 11 880438 0.25651 850418 0.61173
57 4 12 1052020 0.24966 1011170 0.58088
58 4 13 1193680 0.27392 951934 0.57205
59 4 14 1303390 0.37113 881323 0.59457
60 4 15 1436970 0.42141 831374 0.58553
61 5 1 91361 0.05103 118222 0.44288
62 5 2 95428 0.05265 116223 0.46247
63 5 3 98187 0.05635 115853 0.51912
64 5 4 115967 0.06695 129372 0.52933
65 5 5 138382 0.07031 243266 0.55780
66 5 6 156228 0.07396 277930 0.55618
67 5 7 183169 0.08495 317273 0.56933
68 5 8 210212 0.09547 358794 0.58347
69 5 9 274024 0.11981 397667 0.63182
70 5 10 356915 0.15005 566672 0.60472
71 5 11 432344 0.14401 848393 0.58792
72 5 12 524294 0.16930 1005740 0.61616
73 5 13 530924 0.17276 958231 0.60587
74 5 14 581447 0.18667 872924 0.59469
75 5 15 610257 0.21328 844622 0.63555
76 6 1 68978 0.03768 117112 0.44854
77 6 2 74904 0.03978 119420 0.47589
78 6 3 83829 0.04433 116087 0.50056
79 6 4 98148 0.05025 122997 0.50034
80 6 5 118449 0.05505 194309 0.52890
81 6 6 133161 0.05246 307923 0.49536
82 6 7 145062 0.05698 323595 0.51034
83 6 8 170711 0.06149 363081 0.51830
84 6 9 199775 0.06903 386422 0.54672
85 6 10 276797 0.09275 564867 0.55428
86 6 11 381478 0.11264 874818 0.51777
87 6 12 506969 0.15415 1013170 0.58005
88 6 13 633388 0.18646 930477 0.55602
89 6 14 804388 0.24685 851676 0.53779
90 6 15 1009500 0.30401 819476 0.52578
;
proc sort data = Airline;
by AirlineID Year;
run;
proc panel data = Airline;
id AirlineID Year;
model lC = lQ lPF LF / fixtwo printfixed DW;
run;
proc panel data = Airline;
id AirlineID Year;
model lC = lQ lPF LF / fdtwo printfixed BW;
run;
