Effects of DIF in MST routing in ILSAs

Large-scale Assessments in Education

An IERI – International Educational Research Institute Journal

Table 1 Descriptive statistics of proficiency parameters (N = 4000 for each country)

	Country	M	SD	μ	σ
High performers	Singapore	621	82	1.21	0.82
	Republic of Korea	606	85	1.06	0.85
	Chinese Taipei	599	97	0.99	0.97
Medium performers	Sweden	501	72	0.01	0.72
	Malta	494	88	− 0.06	0.88
	Malaysia	465	87	− 0.35	0.87
Low performers	Morocco	384	80	− 1.16	0.8
	South Africa	372	87	− 1.28	0.87
	Saudi Arabia	368	86	− 1.32	0.86

Note: The Mean and Standard Deviation for each participant country in TIMSS 2015 was retrieved from http://timssandpirls.bc.edu/timss2015/international-results/timss-2015/mathematics/student-achievement/distribution-of-mathematics-achievement/
SD standard deviation, N sample size, μ mean proficiency parameter, and σ proficiency parameter standard deviation