Table 6 Parameter estimates and measures of fit from lung dataset example for regular and k-means shared frailty models for 6 -8 groups

Coefficient regular

Coefficient k-means

Parameter

6 groups

7 groups

8 groups

6 groups

7 groups

8 groups

Trt

0.4718

0.4718

0.4718

0.4511

0.4524

0.4511

Ns basis 1

0.7456

0.7456

0.7456

0.7764

0.7774

0.7802

Ns basis 2

0.3552

0.3552

0.3552

0.3843

0.3826

0.3872

Ns basis 3

2.3404

2.3404

2.3404

2.4412

2.4460

2.4460

Ns basis 4

1.0204

1.0204

1.0204

1.0055

1.0088

1.0088

Standard error regular

Standard error k-means

Parameter

6 groups

7 groups

8 groups

6 groups

7 groups

8 groups

Trt

0.1201

0.1201

0.1201

0.1174

0.1176

0.1174

Ns basis 1

0.6215

0.6215

0.6215

0.6211

0.6212

0.6211

Ns basis 2

0.5182

0.5182

0.5182

0.5138

0.5137

0.5136

Ns basis 3

1.5051

1.5051

1.5051

1.5038

1.5037

1.5028

Ns basis 4

0.6395

0.6395

0.6395

0.6353

0.6360

0.6353

p-values regular

p-values k-means

Parameter

6 groups

7 groups

5 groups

3 groups

4 groups

5 groups

Trt

< 0.0001

< 0.0001

< 0.0001

0.0001

0.0001

0.0001

Ns basis 1

0.2303

0.2303

0.2303

0.2113

0.2108

0.2091

Ns basis 2

0.4931

0.4931

0.4931

0.4545

0.4563

0.4510

Ns basis 3

0.1200

0.1200

0.1200

0.1045

0.1047

0.1036

Ns basis 4

0.1105

0.1105

0.1105

0.1135

0.1127

0.1124

p-values for non-linearity

0.0003

0.0003

0.0003

0.2047

0.1940

0.1865

AIC

1466.74

1466.74

1466.74

1477.58

1477.43

1477.37

MSE

2.13

2.13

2.13

1.90

1.90

1.90

Frailty variance

0.017

0.017

0.017

0.0007

0.0007

0.0007

Mean time

305.23