. 2023 Jun 1;9(6):e16840. doi: 10.1016/j.heliyon.2023.e16840

Table 5.

Effects of peer characteristics examined in previous CEPS-based studies.

Outcome variable: standardized 8th-grade test scores	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
	A. Chinese
Classmates' average 7th-grade Chinese test score	−0.034 (0.069)	−0.010 (0.072)	−0.043 (0.079)	−0.017 (0.071)	−0.033 (0.071)	−0.037 (0.071)	−0.041 (0.077)	−0.043 (0.070)
Proportion of [peers] in the class:
Girls [14]	Yes
Migrant children [15,16]		Yes
Repeaters [21]			Yes
Classmates with alcoholic fathers [19]				Yes
Only-child classmates [18]					Yes
Family backgrounds of Grade-7 classmates:
Mean years of fathers' education						Yes
Mean years of mothers' education							Yes
Proportion of peers in non-poor households								Yes
Controls (full set, with school fixed effects)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
N	4018	4018	4018	4018	4018	4018	4018	4018
R²	0.552	0.552	0.548	0.545	0.552	0.557	0.557	0.558
	B. Mathematics
Classmates' average 7th-grade mathematics test score	0.131** (0.063)	0.141** (0.062)	0.093 (0.060)	0.137** (0.064)	0.133** (0.064)	0.119* (0.063)	0.114* (0.063)	0.121** (0.060)
Proportion of [peers] in the class:
Girls [14]	Yes
Migrant children [15,16]		Yes
Repeaters [21]			Yes
Classmates with alcoholic fathers [19]				Yes
Only-child classmates [18]					Yes
Family backgrounds of 7th-grade classmates:
Mean years of fathers' education						Yes
Mean years of mothers' education							Yes
Proportion of peers in non-poor households								Yes
Controls (full set, with school fixed effects)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
N	4018	4018	4018	4018	4018	4018	4018	4018
R²	0.600	0.601	0.601	0.598	0.601	0.606	0.606	0.613
	C. English
Classmates' average 7th-grade English test score	0.111*** (0.035)	0.118*** (0.032)	0.140*** (0.044)	0.117*** (0.035)	0.124*** (0.036)	0.110*** (0.040)	0.090** (0.039)	0.128** (0.051)
Proportion of [peers] in the class:
Girls [14]	Yes
Migrant children [15,16]		Yes
Repeaters in primary school [21]			Yes
Classmates with alcoholic fathers [19]				Yes
Only-child classmates [18]					Yes
Family backgrounds of 7th-grade classmates':
Mean years of fathers' education						Yes
Mean years of mothers' education							Yes
Proportion of peers in non-poor households								Yes
Controls (full set, with school fixed effects)	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
N	4018	4018	4018	4018	4018	4018	4018	4018
R²	0.700	0.699	0.699	0.698	0.700	0.709	0.709	0.710

Notes: The sample includes 52 schools that randomly assigned newly-enrolled students to 7th-grade classes but did not reassign students in 8th grade. “Controls” include the full set of control variables (i.e., students' own subject-specific 7th-grade test scores, personal, family, and teacher characteristics, and school fixed effects) reported in Table 4. Standard errors in parentheses, clustered at the class level. *p < 0.1, **p < 0.05, ***p < 0.01.