Classic data set for the choice of class intervals for choropleth maps.
Format
A data frame with 102 observations on the following 2 variables.
jenks71
: a numeric vector: Per acre value of gross farm products in dollars by county for Illinois in #' 1959area
: a numeric vector: county area in square miles
Source
Jenks, G. F., Caspall, F. C., 1971. "Error on choroplethic maps: definition, measurement, reduction". Annals, Association of American Geographers, 61 (2), 217–244
Examples
data(jenks71)
jenks71
#> jenks71 area
#> 1 50.12 619.1250
#> 2 83.90 564.8666
#> 3 76.43 519.2851
#> 4 71.61 470.0023
#> 5 79.66 611.0690
#> 6 84.84 281.9802
#> 7 87.87 763.3878
#> 8 92.45 465.8562
#> 9 119.90 524.0520
#> 10 155.30 957.0728
#> 11 131.50 634.9357
#> 12 111.80 336.5958
#> 13 96.78 697.2824
#> 14 86.75 729.3617
#> 15 62.41 849.4304
#> 16 96.37 322.6725
#> 17 75.51 451.4319
#> 18 77.29 1147.8980
#> 19 85.41 873.4952
#> 20 116.40 825.9242
#> 21 58.50 430.4035
#> 22 75.29 569.4754
#> 23 66.32 172.2371
#> 24 62.65 681.3121
#> 25 80.45 288.2996
#> 26 72.76 720.1658
#> 27 63.67 398.5411
#> 28 60.27 1045.4367
#> 29 68.45 395.4899
#> 30 100.10 543.6524
#> 31 55.30 1117.9663
#> 32 54.07 486.3734
#> 33 57.49 631.0993
#> 34 73.52 542.7184
#> 35 68.25 1186.3229
#> 36 64.28 658.0177
#> 37 50.64 883.1348
#> 38 52.47 815.7020
#> 39 68.19 590.6621
#> 40 57.40 902.1977
#> 41 39.72 563.7366
#> 42 60.66 997.4052
#> 43 57.59 619.1182
#> 44 38.22 441.7262
#> 45 57.22 405.0457
#> 46 67.04 440.3459
#> 47 47.29 872.4719
#> 48 71.05 315.5443
#> 49 50.53 383.6820
#> 50 34.63 307.4830
#> 51 59.65 585.2796
#> 52 62.06 877.4056
#> 53 52.89 624.1747
#> 54 56.35 417.3518
#> 55 57.26 572.6364
#> 56 53.77 849.8499
#> 57 59.89 715.7982
#> 58 55.44 344.4581
#> 59 45.40 252.9370
#> 60 52.21 510.0139
#> 61 49.38 767.9963
#> 62 51.15 709.8996
#> 63 54.27 867.8165
#> 64 54.32 546.7774
#> 65 41.20 504.9391
#> 66 34.58 283.8793
#> 67 50.11 347.0351
#> 68 52.05 377.2332
#> 69 33.82 725.3493
#> 70 39.88 479.8502
#> 71 36.24 446.6893
#> 72 41.02 497.9817
#> 73 46.13 382.7055
#> 74 51.15 740.6097
#> 75 32.28 469.8219
#> 76 33.26 373.2986
#> 77 31.78 362.0195
#> 78 31.28 575.7414
#> 79 50.52 503.4115
#> 80 47.21 674.2223
#> 81 32.69 715.4710
#> 82 38.30 229.4964
#> 83 33.83 222.6388
#> 84 40.30 397.9347
#> 85 40.62 564.3519
#> 86 32.14 583.6990
#> 87 31.66 502.5933
#> 88 26.09 435.8743
#> 89 39.84 597.3510
#> 90 24.83 446.9202
#> 91 28.20 431.3176
#> 92 31.19 602.6493
#> 93 37.57 332.2962
#> 94 27.16 386.9290
#> 95 23.42 444.3156
#> 96 18.57 348.8593
#> 97 30.97 422.1927
#> 98 17.82 374.5757
#> 99 15.57 181.7830
#> 100 15.93 242.0478
#> 101 28.71 252.5336
#> 102 32.22 202.8932