Skip to main content

An IERI – International Educational Research Institute Journal

Table 2 Relative average root mean square error (RMSE) for cross-sectional estimates and trend estimates in country means and country standard deviations based on the 1PL model for assessment design Des1 (I0 = 30, I1 = 0, I2 = 0), Design Des2 (I0 = 30, I1 = 30, I2 = 0), and Design Des3 (I0 = 30, I1 = 30, I2 = 30)

From: Comparing different trend estimation approaches in country means and standard deviations in international large-scale assessment studies

Design

Model

Link

Inv

Items

1PL NODIF

1PL UDIF

N

N

500

1000

2500

500

1000

2500

 

Cross-sectional mean

       

Des1

I1

Indirect

Yes

All

100.0

100.0

100.0

100.0

100.0

100.0

I2

Indirect

No

All

100.2

100.3

100.1

98.2

98.4

97.3

 

Cross-sectional standard deviation

     

Des1

I1

Indirect

Yes

All

100.0

100.0

100.0

100.0

100.0

100.0

I2

Indirect

No

All

102.6

102.7

102.1

80.8

69.9

52.4

 

Trend in mean

        

Des1

I1

Indirect

Yes

All

100.0

100.0

100.0

100.0

100.0

100.0

I2

Indirect

No

All

100.1

100.2

100.1

99.2

98.7

98.2

D2

Direct

No

All

100.1

100.2

100.1

99.2

98.7

98.2

Des2

I1

Indirect

Yes

All

100.0

100.0

100.0

100.0

100.0

100.0

I2

Indirect

No

All

100.3

100.3

100.3

99.2

98.9

98.6

I3

Indirect

Yes

Link

103.8

104.1

104.0

89.8

84.9

81.4

I4

Indirect

No

Link

104.5

104.8

104.6

89.6

84.2

80.1

D2

Direct

No

All

104.3

104.6

104.5

89.6

84.4

80.2

D4

Direct

No

Link

104.5

104.8

104.6

89.6

84.2

80.1

Des3

I1

Indirect

Yes

All

100.0

100.0

100.0

100.0

100.0

100.0

I2

Indirect

No

All

100.5

100.3

100.3

99.0

98.5

98.2

I3

Indirect

Yes

Link

107.4

107.0

107.7

93.3

90.6

84.5

I4

Indirect

No

Link

108.7

107.8

108.6

93.2

90.0

83.3

D2

Direct

No

All

108.3

107.5

108.4

93.1

90.0

83.4

D4

Direct

No

Link

108.7

107.8

108.6

93.2

90.0

83.3

 

Trend in standard deviation

      

Des1

I1

Indirect

Yes

All

100.0

100.0

100.0

100.0

100.0

100.0

I2

Indirect

No

All

102.1

102.5

102.3

97.8

93.3

83.9

D2

Direct

No

All

102.1

102.5

102.3

97.8

93.3

83.9

Des2

I1

Indirect

Yes

All

100.0

100.0

100.0

100.0

100.0

100.0

I2

Indirect

No

All

102.4

101.9

102.2

92.5

84.8

72.2

I3

Indirect

Yes

Link

111.5

110.9

111.1

107.1

100.9

96.8

I4

Indirect

No

Link

114.9

114.3

114.6

103.8

93.6

80.8

D2

Direct

No

All

102.4

101.9

102.2

92.5

84.8

72.2

D4

Direct

No

Link

114.9

114.3

114.6

103.8

93.6

80.8

Des3

I1

Indirect

Yes

All

100.0

100.0

100.0

100.0

100.0

100.0

I2

Indirect

No

All

102.5

102.3

102.3

93.7

87.8

73.7

I3

Indirect

Yes

Link

119.3

119.8

121.1

117.1

113.1

103.1

I4

Indirect

No

Link

124.5

124.3

126.1

115.4

107.6

90.5

D2

Direct

No

All

102.5

102.3

102.3

93.7

87.8

73.7

D4

Direct

No

Link

124.5

124.3

126.1

115.4

107.6

90.5

  1. Inv assumption of invariant item parameters across countries; indirect indirect linking; direct direct linking; NODIF no differential item functioning; UDIF uniform differential item functioning; NUDIF nonuniform differential item functioning. Method I1 (original trend) was used as the reference for computing the relative RMSE. RMSE entries smaller than 100 are printed in bold