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UNDERSTANDING THE DATABASE
Guide
Methodology
Introduction
Coverage of the Slave Trade
Nature of Sources
Cases and Variables
Data Variables
Dates
Names
Imputed Variables
Geographic Data
Imputed Voyage Dates
Classification as a Trans-Atlantic Slaving Voyage
Voyage Outcomes
Inferring Places of Trade
Imputing Numbers of Slaves
Regions of Embarkation and Disembarkation
Age and Gender Ratios
National Carriers
Tonnage
Resistance and Price of Slaves
Appendix
Notes
Variable List
Sources
Documentary Sources
Newspapers
Published Sources
Unpublished Secondary Sources
Private Notes and Collections

Construction of the Trans-Atlantic Slave Trade Database: Sources and Methods

David Eltis (Emory University), 2007

Appendix

Derivation of Estimated number of Captives Carried on Vessels in the Voyages Database for which such Information cannot be obtained from the Sources

Voyage groupings for estimating imputed slaves Average number of captives embarked number Sd Average number of captives disembarked number sd
Spanish, America, pre-1626 200.1 202 91 166.7 202 91
Spanish, America, 1626-41 294 6 148.6 152.9 148 98.4
Steamer 897.3 6 259.8 1004.5 17 399.9
pre1716 French 337.7 77 166.6 241.5 103 134
Sumaca, pre-1751 211.5 14 68.1 229.6 25 170.4
Sumaca, 1751-76 290.2 73 82.4 223.8 60 89.7
Sumaca, 1776-1800 342.9 33 134.6 256.5 93 133
Sumaca, 1800-25 226.2 50 100.4 217.6 75 94.6
Sumaca,1826-66 317.4 10 102.2 241.5 13 107.4
pre-1650 Dutch 293.6 94 172.7 227.8 25 142.3
1650-73 Dutch 369.8 14 325.5 273.8 22 95.1
1674-1730Dutch 506.5 45 150.9 447.6 140 148.2
post1730Dutch 427.8 24 180.5 284.3 442 105.7
pre-1801 Bahia 488.9 10 280 469.4 9 268.7
1801-25 Bahia 246 4 187.1 245.3 13 165.7
post-1825 Bahia 367.3 35 162.6 330.1 47 156.1
Balandra 223.3 4 124.6 129.3 36 89.5
Barque, pre-1826 121.3 4 89.4 174.7 6 43.3
Barque, 1826-50 614.3 8 371.3 638.3 63 237.1
Barque, 1851-75 821.9 9 300.8 655.5 23 212.5
Barqua 572.4 16 143.7 516.5 20 127
B. of Benin, pre-1700 418.5 86 153.1 308.3 131 137.3
B. of Benin, 1700-1800 356.3 513 130.7 313.1 533 129.1
B. of Benin, post-1800 344.5 10 165 439 9 183.9
Bergantine pre-1776 246.8 19 97.6 193.7 39 137.7
Bergantine, 1776-1800 314.7 46 157.2 249.7 91 134.8
Bergantine,1801-25 417.5 562 147.4 352.8 783 135.7
Bergantine, 1826-75 454.9 134 129.1 419.6 147 132.2
B. of Biafra, pre-1700 229.4 44 90.4 175 109 68.6
B. of Biafra, 1700-1800 263.9 140 122.4 208.8 326 102.2
B. of Biafra, post-1800 311.5 52 166.6 261.8 29 142.3
Brig, pre-1751 150 1 . 151.7 49 54.2
Brig, 1751-75 141.6 26 74.3 150.1 112 64.3
Brig, 1776-1800 201.1 86 75.5 198.1 243 76
Brig,1801-25 332.9 140 139.8 265.2 293 138.5
Brig, 1826-50 455.5 263 169.1 441.5 538 161.4
Brig, post-1850 489.1 7 210.2 461.6 36 140.3
Brigantine, pre-1776 142.7 44 66.6 131.3 307 58.2
Brigantine, 1776-1800 111 1 . 216.6 11 65.9
Brigantine,1801-25 206.1 7 83.6 255.9 121 118.4
Brigantine, 1825-50 372 79 182.7 361.1 159 163.5
Brigantine, post-1850 471.3 7 286.5 480.1 28 199.8
Buque, pre-1726 406.2 6 102.1 319.7 30 122.5
Buque, 1726-1825 409 1 . 228.5 11 113
Chalupa 235 4 72.4 152.9 13 78.4
Charrua 329 5 131.1 319.3 7 133
Curveta, pre-1751 335.5 75 83.5 272.2 50 95
Curveta, 1751-75 348.9 217 106.7 277.3 199 112.1
Curveta, 1776-1800 371.7 210 162.9 323.5 343 145.8
Curveta, post-1800 496.7 172 125.9 435.7 195 120.9
Danish, pre-1794 228.9 8 73.7   0 0
Danish, 1794-1806 248.8 4 134.6 104.3 34 65.3
Felucca 246.8 5 207.2 340.2 26 148.3
Fluit 440.3 19 139 391 29 145.1
Fregata, pre-1726 349.8 34 134.3 299 56 155.2
Fregata, 1726-75 348.5 88 103.6 310.4 123 126.4
Fregata, 1776-1800 303.5 21 191.4 259.2 64 102.3
Fregata, 1801-75 229.9 21 181 265.7 88 155.2
Galera 1751-76 400.7 69 190.1 285.6 90 183.5
Galera 1776-1800 371.7 67 205 335.7 79 194.4
Galera 1801-25 548.2 206 150 472.3 224 148.2
Galera 1851-76 600.5 62 164.2 536.8 70 150.5
Galera pre-1751 444 114 129.6 403.3 157 141.5
Galeta1826-50 321.5 11 160.4 267.8 27 145.3
Galeta1851-75 423.5 2 470.2 345.3 7 273
Galeta pre-1826 161.8 6 94.2 209 250 99.4
Gold Coast 1700 262.4 276 127.8 236.7 400 100.4
Gold Coast pre-1700 316.9 36 208.1 242.2 52 141.5
Iate1826-75 421.6 7 155.2 282 48 138.8
Iatepre1826 296.5 57 136.4 245.4 52 147.7
Navio mercante 454.7 80 130.6 410.6 44 139.6
No rig1651-75 306 5 135.1 261.3 32 194.4
No rig1676-1700 418.4 8 230.3 196.9 134 126.9
No rig1701-25 259.8 15 159.1 191.2 451 96.7
No rig1726-50 252.8 32 142.1 219.4 206 103
No rig1751-75 303.9 38 162.8 208.8 137 124
No rig1776-1800 331.9 34 138.8 262.3 133 137
No rig1801-25 287.9 16 137.7 195.8 37 128.1
No rig1826-50 387 6 421.7 444.3 109 236.2
No rig1851-75 658.3 4 192.7 493.5 84 194.7
North American pre-1851 151.6 49 110 129.4 98 121.7
Paquete 302 4 86.4 211 7 118
Patacho 306.4 63 100.7 335.3 164 105.4
Penque 363.5 11 116.8 259.8 8 111.5
Pilot boat 273.5 2 37.5 270.8 13 133.8
Polacca 738.7 3 300 428.9 27 231.8
Schooner 1776-1800 107.1 31 55.5 104 104 50.2
Schooner, 1801-1825 207.1 106 145.4 167.5 220 111.5
Schooner 1826-1850 264.2 249 117.9 278.7 488 137.5
Schooner 1851-1875 327.7 13 243 322.2 26 171.1
Schooner brig 322 35 97.4 335.8 86 111.3
Schooner pre-1776 67.9 10 34.8 100.6 50 85.9
Southeast Africa 1700-1800 425.1 14 210.9 266.6 72 121.6
Southeast Africa post-1800 451.3 27 190 403.9 28 178.8
Southeast Africa pre-1700 129.5 4 57 192.3 18 77.3
Senegambia 1700-1800 183.3 160 133.3 149.6 262 103.1
Senegambia post-1800 123.6 13 99.9 159 16 94.2
Senegambia pre1700 218.5 43 129.7 155.3 43 70.4
Ship 1726-1750 335 15 124.5 297.6 289 126.7
Ship 1751-1775 351.3 160 127 287.3 658 105.6
Ship 1776-1800 355 503 123.9 329.2 1367 118.7
Ship 1801-1825 400.1 32 167.6 278.8 648 79.1
Ship 1826-1850 597 21 263 532.7 29 199.8
Ship 1851-75 915.3 3 257.1 768.7 9 154.9
Ship pre-1726 291.7 39 148.6 213.8 132 107
Sierra Leone 1700-1800 204.9 59 156 205.7 115 136.9
Sierra Leone post-1800 246.7 23 163 245.5 16 180.2
Sloop 1751-76 82.9 22 31.8 66.6 71 36.2
Sloop 1776-1800 94.4 8 80.5 92.9 36 41.5
Sloop 1801-76 128 4 59.2 101.4 10 54.9
Sloop pre1751 123.4 15 69.4 108.2 92 38.8
Sierra Leone pre-1700 126.9 12 26.2 92.5 13 39.5
Smack 314 7 128.3 257.3 57 112.3
Small craft 111.7 12 68.2 99.6 35 55.6
Snow 1726-50 195.9 9 26.7 194.8 185 70.2
Snow 1751-75 220.2 102 92.5 201.1 557 70.9
Snow 1776-1800 258.3 28 78.5 210.7 59 85.3
Snow 1801-76 192 2 18.4 167.6 13 47.2
Snow pre-1726 165.7 3 51.1 119.8 30 45.2
Spanish 1642-1662 314.6 9 321.6 250.9 17 219
US barque 1826-75 743 13 215 569.7 28 177.7
US brig 1776-1800 108 55 26.6 107.4 44 55.9
US brig 1801-25 127.9 79 46.1 129.4 100 56
US brigantine 1776-1825 83.3 3 33.3 125.6 26 46.9
US brigantine post1825 420.3 4 136.8 436.5 12 158.1
US brigantine pre-1776 99.1 9 51.2 100.1 22 40.6
US brig post-1825 595.5 11 130.6 557.6 30 145.4
US brig pre-1776 127.3 54 46.3 103.5 69 44.9
US schooner, 1776-1800 80.6 48 38.6 76.1 43 36.6
US schooner, 1801-1825 90 29 18.2 88 80 28.9
US schooner, 1826-75 405.4 7 201.2 398.2 13 169.3
US schooner, pre-1776 75.3 18 35 74 24 35.7
US ship1776-1800 165.9 31 81.4 166.5 30 93.8
US ship1801-1825 214.7 47 91 197.1 54 95.2
US ship post-1825 1126.8 6 210.1 1003 10 331.4
US ship pre-1776 188.3 22 82.4 155.2 36 72.7
US sloop 80.1 141 31.2 70.1 141 31.8
US snow 115.9 53 38.7 119.8 41 66.7
W Central Africa 1700-1800 382.7 477 148.7 351.9 859 139.9
W Central Africa post-1800 419.1 63 162.9 372 76 161.7
W Central Africa pre-1700 369.2 19 175.2 331 54 135.6
Windward C. 1700-1800 219.5 23 112.5 177.8 51 102.2

Resistance and Price of Slaves Notes
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