Skip to main content

Table 4 K-anonymity for each perturbation and with different amounts of data release

From: Measuring the impact of spatial perturbations on the relationship between data privacy and validity of descriptive statistics

Perturbation method

100% of data

75% of data

50% of data

Points per km2

K < 10

K < 5

Min K

Mean K

Points per km2

K < 10

K < 5

Min K

Mean K

Points per km2

K < 10

K < 5

Min K

Mean K

Original data

211.27

1

0.9938

1

1.3699

158.48

1

1

1

1.2745

105.63

1

1

1

1.1798

Random perturbation 50 m

211.27

0.7509

0.5395

1

6.9993

158.48

0.8183

0.6093

1

5.4984

105.63

0.9042

0.7057

1

3.9531

Random perturbation 250 m

211.27

0.1309

0.0644

1

77.2057

158.48

0.1669

0.0839

1

58.9595

105.63

0.2267

0.1146

1

38.7753

Random perturbation 500 m

211.27

0.0415

0.0173

1

219.025

158.48

0.0523

0.0263

1

166.9783

105.63

0.078

0.0365

1

110.491

Random weighted perturbation 5 NN

211.27

0.9672

0.7738

1

3.3728

158.48

0.9839

0.8515

1

2.7956

105.63

0.9921

0.9328

1

2.1738

Random weighted perturbation 50 NN

211.27

0.2326

0.0928

1

26.1316

158.48

0.3041

0.132

1

19.9167

105.63

0.4385

0.1951

1

14.0489

Donut between 5 and 50 m

211.27

0.7565

0.5323

1

6.9296

158.48

0.8209

0.6017

1

5.4299

105.63

0.9111

0.7195

1

3.9086

Donut between 50 and 250 m

211.27

0.1015

0.042

1

78.3049

158.48

0.1389

0.0579

1

60.0471

105.63

0.2084

0.0928

1

39.7427

Affine shear

211.27

0.0654

0.0331

1

537.758

158.48

0.0787

0.0395

1

407.0853

105.63

0.1012

0.0553

1

272.196

Voronoi masked

211.27

1

0.9911

1

1.902

158.48

1

0.999

1

1.681

105.63

1

1

1

1.4538

Grid center w/100 m cells

211.27

0.4852

0.2309

1

16.3402

158.48

0.5329

0.2956

1

12.7643

105.63

0.6405

0.4227

1

8.5289

Grid center w/250 m cells

211.27

0.0881

0.0393

1

66.0889

158.48

0.1172

0.055

1

50.1178

105.63

0.1936

0.0894

1

33.7496

Grid line w/100 m cells

211.27

0.8333

0.636

1

5.3649

158.48

0.8756

0.7143

1

4.2074

105.63

0.9467

0.7975

1

3.1274

Grid line w/250 m cells

211.27

0.4743

0.2859

1

19.6706

158.48

0.5467

0.3377

1

15.1968

105.63

0.6563

0.4163

1

10.1891

Perturbation method

25% of data

10% of data

Points per km2

K < 10

K < 5

Min K

Mean K

Points per km2

K < 10

K < 5

Min K

Mean K

Original data

52.79

1

1

1

1.081

21.13

1

1

1

1.0346

Random perturbation 50 m

52.79

0.9901

0.8913

1

2.3241

21.13

1

0.963

1

1.6296

Random perturbation 250 m

52.79

0.3893

0.2243

1

19.2826

21.13

0.6321

0.3877

1

9.3901

Random perturbation 500 m

52.79

0.1492

0.0731

1

56.6166

21.13

0.2988

0.1728

1

22.8

Random weighted perturbation 5 NN

52.79

0.999

0.9832

1

1.6136

21.13

1

0.9951

1

1.2864

Random weighted perturbation 50 NN

52.79

0.7658

0.4071

1

7.1897

21.13

0.958

0.7432

1

3.5259

Donut between 5 and 50 m

52.79

0.9881

0.8498

1

2.4496

21.13

1

0.9704

1

1.6074

Donut between 50 and 250 m

52.79

0.3607

0.167

1

19.3142

21.13

0.6222

0.3506

1

9.6173

Affine shear

52.79

0.1542

0.0939

1

136.2579

21.13

0.2049

0.1432

1

53.4469

Voronoi masked

52.79

1

1

1

1.2036

21.13

1

1

1

1.1111

Grid center w/100 m cells

52.79

0.8794

0.6077

1

4.6285

21.13

0.9753

0.8272

1

2.7086

Grid center w/250 m cells

52.79

0.3745

0.1611

1

16.5237

21.13

0.7062

0.3679

1

7.9877

Grid line w/100 m cells

52.79

0.999

0.9328

1

1.9713

21.13

1

0.9827

1

1.4889

Grid line w/250 m cells

52.79

0.83

0.6047

1

5.4229

21.13

0.9506

0.7975

1

3.0469

Back to article page

International Journal of Health Geographics

ISSN: 1476-072X