Is Weight Influenced by Peers: An Empirical Research Based on Classroom Units

doi:10.16382/j.cnki.1000-5560.2023.12.008

Abstract

Abstract:

The research of peer effects on weight is important for clarifying the generating process of abnormal weight, as well as promoting the social governance of adolescent physical health development. Based on the social interaction theory and a combination of data from the 2013-2014 and 2014-2015 academic years of the China Education Panel Survey (CEPS), this study aimed to identify the weight peer effect of adolescents within classes and the underlying mechanisms. It was found that there was a weight peer effect within the class unit, with peer mean BMI and peer overweight and obesity rates significantly and positively affecting individual BMI. The results consistently held after controlling for contextual and corrlated effects, performing instrumental variable treatment, and conducting robustness tests. Further mechanism analysis showed that weight perception played a moderating role in the occurrence of the weight peer effect, and that overestimating one’s own weight significantly weakened the weight peer effect, while underestimating one’s own weight has no effect on it. Accordingly, it was demonstrated that the countermeasures against abnormal weight of adolescents in the school context have good externalities, and suggestions such as reasonable allocation of health education resources, enrichment of health education work content, and close attention to social experiences of student groups were proposed.

Key words: weight, overweight, obesity, peer effect, classroom

Sihui Du, Gang Cheng, Wenshan Yu. Is Weight Influenced by Peers: An Empirical Research Based on Classroom Units[J]. Journal of East China Normal University(Educational Sciences), 2023, 41(12): 85-99.

Figures/Tables 7

分类	名称	操作化定义	平均值	标准差	样本量
被解释变量	个体BMI	个体体重（kg）÷身高（m）的平方	19.390	3.684	6875
核心解释变量	同伴平均BMI	班级内其他个体的平均BMI	19.390	1.015	6875
核心解释变量	同伴超重肥胖率	班级内其他个体的超重肥胖率，按2014年《国家学生体质健康标准》进行判断与计算	0.153	0.094	6875
基准控制变量	性别	男=1，女=0	0.512	0.500	6875
	户口	农业=1，其他=0	0.467	0.499	6628
	是否独生子女	是=1，否=0	0.508	0.500	6813
	是否寄宿	是=1，否=0	0.225	0.418	6745
	健康自评情况	“很不好”=1至“很好”=5	3.890	0.934	6834
	体育锻炼时间	每周参与体育锻炼的小时数	2.693	3.442	6875
	致胖食品食用频率	“从不”=1至“总是”=5	2.716	0.805	6826
	致胖饮品饮用频率	“从不”=1至“总是”=5	2.862	0.865	6806
	父母最高受教育年限	父母双方受教育年限的最大值	11.132	3.404	6875
	家庭经济条件自评	“非常困难”=1至“很富裕”=5	3.003	0.589	6845
情境效应	同伴身材自评情况	“很瘦”=1至“很胖”=5，取班级内其他个体作答情况的平均值	3.181	0.179	6875
关联效应	基线时期BMI	基线时期个体体重（kg）÷身高（m）的平方	18.599	3.472	6214
	班级规模	班级总人数	44.113	11.305	6875
	班级排名	“最差”=1至“最好”=5，以各班班主任作答结果为准	3.464	1.020	6875
	班主任性别	男=1，女=0	0.312	0.464	6875
	班主任教龄	班主任从事教学工作的连续年限	16.446	8.206	6875
	学校排名	“最差”=1至“最好”=5，以各校校领导作答结果为准	4.057	0.793	6875
	学校位置	“农村”=1至“市/县城的中心城区”=5，以校领导作答结果为准	2.230	1.591	6875
	学校运动环境	操场、运动场、体育馆、游泳池的建设数量	2.112	0.705	6875
工具变量	基线时期同伴平均BMI	基线时期班级内其他个体的平均BMI	18.588	1.038	6875
工具变量	同伴与祖辈同住比例	班级内其他个体与祖辈同住的比例	0.307	0.133	6875
调节变量	是否错误感知自身体重	是=1，否=0	0.474	0.499	6836
	是否高估自身体重	是=1，否=0	0.192	0.394	6836
	是否低估自身体重	是=1，否=0	0.282	0.450	6836

References 0

	曹佃省, 鲁媛, 雷家萍, 毛春梅, 姚应平. 青少年的外貌关注、外貌评价、肥胖焦虑、体质量自评与瘦身追求中国心理卫生杂志 2014 28 05 356 360 曹佃省, 鲁媛, 雷家萍, 毛春梅, 姚应平. (2014). 青少年的外貌关注、外貌评价、肥胖焦虑、体质量自评与瘦身追求. 中国心理卫生杂志,28(05),356—360.
	曹妍. 大陆移民学生如何影响香港本地学生的学业成就?——基于PISA数据的同伴效应实证研究教育与经济 2013 04 47 55 曹妍. (2013). 大陆移民学生如何影响香港本地学生的学业成就?—基于PISA数据的同伴效应实证研究. 教育与经济,(04),47—55.
	陈丽. 工具变量模型在卫生政策效果评价中的应用分析中国卫生经济 2016 05 9 12 陈丽. (2016). 工具变量模型在卫生政策效果评价中的应用分析. 中国卫生经济,(05),9—12.
	陈媛媛, 董彩婷, 朱彬妍. 流动儿童和本地儿童之间的同伴效应: 孰轻孰重? 经济学(季刊) 2021 02 511 532 陈媛媛, 董彩婷, 朱彬妍. (2021). 流动儿童和本地儿童之间的同伴效应: 孰轻孰重?. 经济学(季刊),(02),511—532.
	成刚, 孙志军, 杜思慧. 儿童青少年健康影响学业成绩吗? 教育经济评论 2021 02 46 70 成刚, 孙志军, 杜思慧. (2021). 儿童青少年健康影响学业成绩吗?. 教育经济评论,(02),46—70.
	成刚, 陈瑾, 张田书. 青少年体重影响因素研究——基于中国教育追踪调查的实证分析教育学术月刊 2022 07 74 83 成刚, 陈瑾, 张田书. (2022). 青少年体重影响因素研究—基于中国教育追踪调查的实证分析. 教育学术月刊,(07),74—83.
	杜育红, 郭艳斌. 初中生的同伴效应: 基于发育成熟度的自然实验教育与经济 2019 03 40 48 杜育红, 郭艳斌. (2019). 初中生的同伴效应: 基于发育成熟度的自然实验. 教育与经济,(03),40—48.
	黄依梵, 马莉萍. 大学生餐饮消费的室友同伴效应——基于校园卡餐饮消费的实证研究青年研究 2022 03 74 84+96 黄依梵, 马莉萍. (2022). 大学生餐饮消费的室友同伴效应—基于校园卡餐饮消费的实证研究. 青年研究,(03),74—84+96.
	李强. 同伴效应对中国农村青少年体重的影响中国农村经济 2014 03 73 84 李强. (2014). 同伴效应对中国农村青少年体重的影响. 中国农村经济,(03),73—84.
	李晴晴, 刘毅. 身体意象失调的成因: 基于“镜中自我”的视角心理科学进展 2018 26 11 2013 2023 李晴晴, 刘毅. (2018). 身体意象失调的成因: 基于“镜中自我”的视角. 心理科学进展,26(11),2013—2023.
	林文声, 王志刚, 王美阳. 农地确权、要素配置与农业生产效率——基于中国劳动力动态调查的实证分析中国农村经济 2018 08 64 82 林文声, 王志刚, 王美阳. (2018). 农地确权、要素配置与农业生产效率—基于中国劳动力动态调查的实证分析. 中国农村经济,(08),64—82.
	刘浩. 班级环境对初中生教育期望的影响研究青年研究 2018 418 01 74 85+96 刘浩. (2018). 班级环境对初中生教育期望的影响研究. 青年研究,418(01),74—85+96.
	刘泽云, 郭睿. 流动儿童对本地儿童学习成绩的影响——基于CEPS数据的分析北京大学教育评论 2020 18 4 71 102+187 刘泽云, 郭睿. (2020). 流动儿童对本地儿童学习成绩的影响—基于CEPS数据的分析. 北京大学教育评论,18(4),71—102+187.
	卢富荣, 宋煜静, 刘路培, 等. 隔代教育对孙辈和祖辈的影响: 双刃剑效应心理科学进展 2020 28 10 1733 1741 卢富荣, 宋煜静, 刘路培, 等. (2020). 隔代教育对孙辈和祖辈的影响: 双刃剑效应. 心理科学进展,28(10),1733—1741.
	闵维方, 马莉萍. (2020). 教育经济学. 北京: 北京大学出版社.
	庞祯敬, 李慧. 突发公共卫生事件下公众风险应对行为形成路径研究医学与社会 2022 35 02 1 8+12 庞祯敬, 李慧. (2022). 突发公共卫生事件下公众风险应对行为形成路径研究. 医学与社会,35(02),1—8+12.
	彭林丽, 王宏, 何芳, 等. 重庆市主城区中小学生自我评价体型和减肥行为的关系中国学校卫生 2017 38 02 255 257 彭林丽, 王宏, 何芳, 等. (2017). 重庆市主城区中小学生自我评价体型和减肥行为的关系. 中国学校卫生,38(02),255—257.
	片岡德雄, 吴康宁. 班级社会学探讨华东师范大学学报(教育科学版) 1985 9 03 37 42 片岡德雄, 吴康宁. (1985). 班级社会学探讨. 华东师范大学学报(教育科学版),9(03),37—42.
	权小娟, 朱晓文, 卢春天, 边燕杰. 同伴效应与青少年体重青年研究 2019 04 24 33+94-95 权小娟, 朱晓文, 卢春天, 边燕杰. (2019). 同伴效应与青少年体重. 青年研究,(04),24—33+94-95.
	史攀, 黄于飞, 张翰之, 冷雪晨, 陈红. 消极身体意象对青少年的负面影响心理科学进展 2020 28 02 294 304 史攀, 黄于飞, 张翰之, 冷雪晨, 陈红. (2020). 消极身体意象对青少年的负面影响. 心理科学进展,28(02),294—304.
	王惠芬, 田状状. 布尔迪厄社会实践理论在国内外健康促进中的应用综述医学与社会 2021 34 07 47 51 王惠芬, 田状状. (2021). 布尔迪厄社会实践理论在国内外健康促进中的应用综述. 医学与社会,34(07),47—51.
	王军利, 项立敏, 张松奎, 翟丰. 儿童青少年超重与肥胖的成因及社会网络干预上海体育学院学报 2019 43 05 30 40 王军利, 项立敏, 张松奎, 翟丰. (2019). 儿童青少年超重与肥胖的成因及社会网络干预. 上海体育学院学报,43(05),30—40.
	王梅, 温煦, 吕燕, 等. 家庭结构对于青少年健康行为的影响体育科学 2012 32 05 34 41 王梅, 温煦, 吕燕, 等. (2012). 家庭结构对于青少年健康行为的影响. 体育科学,32(05),34—41.
	吴康宁.(2009) .我国教育社会学的三十年发展(1979—2008). 华东师范大学学报(教育科学版), 27(02), 1−20.
	吴愈晓, 张帆. “近朱者赤”的健康代价: 同辈影响与青少年的学业成绩和心理健康教育研究 2020 41 07 123 142 吴愈晓, 张帆. (2020). “近朱者赤”的健康代价: 同辈影响与青少年的学业成绩和心理健康. 教育研究,41(07),123—142.
	谢维和. 班级: 社会组织还是初级群体教育研究 1998 11 19 24 谢维和. (1998). 班级: 社会组织还是初级群体. 教育研究,(11),19—24.
	杨钋, 朱琼. 初中生同伴关系的影响因素分析北京大学教育评论 2013 03 99 117+192 杨钋, 朱琼. (2013). 初中生同伴关系的影响因素分析. 北京大学教育评论,(03),99—117+192.
	尹志超, 甘犁. 香烟、美酒和收入经济研究 2010 10 90 100+160 尹志超, 甘犁. (2010). 香烟、美酒和收入. 经济研究,(10),90—100+160.
	郑磊. 教育中的社区效应和同伴效应: 方法、证据及政策启示教育学报 2015 05 99 110 郑磊. (2015). 教育中的社区效应和同伴效应: 方法、证据及政策启示. 教育学报,(05),99—110.
	朱旭东. 论教室文化的构建华东师范大学学报(教育科学版) 2020 38 03 57 70 朱旭东. (2020). 论教室文化的构建. 华东师范大学学报(教育科学版),38(03),57—70.
	祝大鹏, 周雯. 体重污名对超重和肥胖人群心理与行为的影响、作用机制与干预武汉体育学院学报 2020 54 12 69 74 祝大鹏, 周雯. (2020). 体重污名对超重和肥胖人群心理与行为的影响、作用机制与干预. 武汉体育学院学报,54(12),69—74. doi: 10.3969/j.issn.1000-520X.2020.12.010
	庄家炽. 参照群体理论评述社会发展研究 2016 3 3 184 197+245-246 庄家炽. (2016). 参照群体理论评述. 社会发展研究,3(3),184—197+245-246.
	Ali, M. M., Amialchuk, A., Gao, S., & Heiland, F. Adolescent weight gain and social networks: Is there a contagion effect? Applied Economics 2012 44 23 2969 2983 Ali, M. M., Amialchuk, A., Gao, S., & Heiland, F. (2012). Adolescent weight gain and social networks: Is there a contagion effect?. Applied Economics, 44(23), 2969—2983. doi: 10.1080/00036846.2011.568408
	Ashikkali, L., Carroll, W., & Johnson, C. The indirect impact of COVID-19 on child health Paediatrics and Child Health 2020 30 12 430 437 Ashikkali, L., Carroll, W., & Johnson, C. (2020). The indirect impact of COVID-19 on child health. Paediatrics and Child Health, 30(12), 430—437. doi: 10.1016/j.paed.2020.09.004
	Brunello, G., Sanz-de-Galdeano, A., & Terskaya, A. Not only in my genes: The effects of peers’ genotype on obesity Journal of Health Economics 2020 72 102349 19 Brunello, G., Sanz-de-Galdeano, A., & Terskaya, A. (2020). Not only in my genes: The effects of peers’ genotype on obesity. Journal of Health Economics, 72, 102349—19. doi: 10.1016/j.jhealeco.2020.102349
	Burke, M. A., & Heliland, F. Social dynamics of obesity Economic Inquiry 2007 45 3 571 591 Burke, M. A., & Heliland, F. (2007). Social dynamics of obesity. Economic Inquiry, 45(3), 571—591. doi: 10.1111/j.1465-7295.2007.00025.x
	Christakis, N. A., & Fowler, J. H. The spread of obesity in a large social network over 32 years The New England Journal of Medicine 2007 357 4 370 379 Christakis, N. A., & Fowler, J. H. (2007). The spread of obesity in a large social network over 32 years. The New England Journal of Medicine, 357(4), 370—379. doi: 10.1056/NEJMsa066082
	Cohen-Cole, E., & Fletcher, J. M. Is obesity contagious? Social networks vs environmental factors in the obesity epidemic. Journal of Health Economics 2008 27 5 1382 1387 Cohen-Cole, E., & Fletcher, J. M. (2008). Is obesity contagious? Social networks vs. environmental factors in the obesity epidemic. Journal of Health Economics, 27(5), 1382—1387.
	Coleman, J. S. (1961). The adolescent society: The social life of the teenager and its impact on education. The Free Press of Glencoe.
	Coleman, J. S. Social capital in the creation of human capital The American Journal of Sociology 1988 94 S95 S120 Coleman, J. S. (1988). Social capital in the creation of human capital. The American Journal of Sociology, 94, S95—S120. doi: 10.1086/228943
	Cunningham, S. A., Vaquera, E., Maturo, C. C., & Venkat Narayan, K. M. Is there evidence that friends influence body weight? A systematic review of empirical research Social Science & Medicine 2012 75 7 1175 1183 Cunningham, S. A., Vaquera, E., Maturo, C. C., & Venkat Narayan, K. M. (2012). Is there evidence that friends influence body weight? A systematic review of empirical research. Social Science & Medicine, 75(7), 1175—1183.
	Ejima, K., Aihara, K., & Nishiura, H. Modeling the obesity epidemic: Social contagion and its implications for control Theoretical Biology & Medical Modelling 2013 10 17 Ejima, K., Aihara, K., & Nishiura, H. (2013). Modeling the obesity epidemic: Social contagion and its implications for control. Theoretical Biology & Medical Modelling, 10, 17.
	Epple, D., & Romano, R. E. (2011). Peer effects in education: A survey of the theory and evidence. In J. Benhabib, A. Bisin, & M. O. Jackson (Eds. ), Handbook of Social Economics (Vol. 1, pp. 1053–1163). North-Holland.
	Festinger, L. A theory of social comparison processes Human Relationship 1954 7 7 117 140 Festinger, L. (1954). A theory of social comparison processes. Human Relationship, 7(7), 117—140.
	Fismen, A. S., Galler, M., Klepp, K. L., & et al. Weight status and mental well-being among adolescents: The mediating role of self-perceived body weight A cross-national survey. Journal of Adolescent Health 2022 71 2 187 195 Fismen, A. S., Galler, M., Klepp, K. L., & et al. (2022). Weight status and mental well-being among adolescents: The mediating role of self-perceived body weight. A cross-national survey. Journal of Adolescent Health, 71(2), 187—195.
	Fraser, B. (1986). Classroom environment. London: Croom Helm Ltd.
	Halliday, T. J., & Kwak, S. Weight gain in adolescents and their peers Economics and Human Biology 2009 7 2 181 190 Halliday, T. J., & Kwak, S. (2009). Weight gain in adolescents and their peers. Economics and Human Biology, 7(2), 181—190. doi: 10.1016/j.ehb.2009.05.002
	Haukoos, G. D., & Penick, J. E. The effects of classroom climate on college science students: A replication study Journal of Research in Science Teaching 1985 22 2 163 168 Haukoos, G. D., & Penick, J. E. (1985). The effects of classroom climate on college science students: A replication study. Journal of Research in Science Teaching, 22(2), 163—168. doi: 10.1002/tea.3660220207
	Have, M., Nielsen, J. H., Gejl, A. K., & et al. Rationale and design of a randomized controlled trial examining the effect of classroom-based physical activity on math achievement BMC Public Health 2016 16 304 Have, M., Nielsen, J. H., Gejl, A. K., & et al. (2016). Rationale and design of a randomized controlled trial examining the effect of classroom-based physical activity on math achievement. BMC Public Health, 16, 304. doi: 10.1186/s12889-016-2971-7
	Kelley, H. H. (1952). Two functions of reference groups. In G. E. Swanson, T. M. Newcomb, & E. L. Hartley (Eds). Readings in Social Psychology (2nd edition). New York: Holt, Rinehart & Winston.
	Leatherdale, S. T., & Papadakis, S. A multi-level examination of the association between older social models in the school environment and overweight and obesity among younger students Journal of Youth and Adolescence 2009 40 3 361 372 Leatherdale, S. T., & Papadakis, S. (2009). A multi-level examination of the association between older social models in the school environment and overweight and obesity among younger students. Journal of Youth and Adolescence, 40(3), 361—372.
	Lim, J., & Meer, J. How do peers influence BMI? Evidence from randomly assigned classrooms in South Korea Social Science & Medicine 2018 197 17 23 Lim, J., & Meer, J. (2018). How do peers influence BMI? Evidence from randomly assigned classrooms in South Korea. Social Science & Medicine, 197, 17—23.
	Manski, C. F. Identification of endogenous social effects: The reflection problem Review of Economic Studies 1993 60 3 531 542 Manski, C. F. (1993). Identification of endogenous social effects: The reflection problem. Review of Economic Studies, 60(3), 531—542. doi: 10.2307/2298123
	Manski, C. F. Economic analysis of social interactions The Journal of Economic Perspectives 2000 14 3 115 136 Manski, C. F. (2000). Economic analysis of social interactions. The Journal of Economic Perspectives, 14(3), 115—136. doi: 10.1257/jep.14.3.115
	Moffitt, R. (2000). Policy interventions, low-level equilibria and social interactions. In B. Durlauf (Eds. ). Social Dynamics (pp. 45-82). Washington DC.
	Mora, T., & Gil, J. Peer effects in adolescent BMI: Evidence from Spain Health Economics 2013 22 5 501 516 Mora, T., & Gil, J. (2013). Peer effects in adolescent BMI: Evidence from Spain. Health Economics, 22(5), 501—516. doi: 10.1002/hec.2817
	Nathanson, A. I., & Botta, R. A. Shaping the effects of television on adolescents’ body image disturbance: The role of parental mediation Communication Research 2003 30 3 304 331 Nathanson, A. I., & Botta, R. A. (2003). Shaping the effects of television on adolescents’ body image disturbance: The role of parental mediation. Communication Research, 30(3), 304—331. doi: 10.1177/0093650203030003003
	Nie, P., Sousa-Poza, A., & He, X. Peer effects on childhood and adolescent obesity in China China Economic Review 2015 35 47 69 Nie, P., Sousa-Poza, A., & He, X. (2015). Peer effects on childhood and adolescent obesity in China. China Economic Review, 35, 47—69. doi: 10.1016/j.chieco.2015.06.002
	Nugent, R., Levin, C., Hale, J., & Hutchinson, B. Economic effects of the double burden of malnutrition The Lancet (British Edition) 2020 395 10218 156 164 Nugent, R., Levin, C., Hale, J., & Hutchinson, B. (2020). Economic effects of the double burden of malnutrition. The Lancet (British Edition), 395(10218), 156—164.
	Paloyo, A. R. (2020). Peer effects in education: Recent empirical evidence. In S. Bradley & C. Green (Eds. ), The Economics of Education (Second Edition) (pp. 291–305). Academic Press.
	Sacerdote, B. (2011). Peer effects in education: How might they work, how big are they and how much do we know thus far? In E. A. Hanushek, S. Machin, & L. Woessmann (Eds. ), Handbook of the Economics of Education (Volume 3, pp. 249–277). Elsevier.
	Sánchez-López, M., Ruiz-Hermosa, A., Redondo-Tébar, A., & et al. Rationale and methods of the MOVI-da10! Study –a cluster-randomized controlled trial of the impact of classroom-based physical activity programs on children’s adiposity, cognition and motor competence BMC Public Health 2019 19 417 Sánchez-López, M., Ruiz-Hermosa, A., Redondo-Tébar, A., & et al. (2019). Rationale and methods of the MOVI-da10! Study –a cluster-randomized controlled trial of the impact of classroom-based physical activity programs on children’s adiposity, cognition and motor competence. BMC Public Health, 19, 417. doi: 10.1186/s12889-019-6742-0
	Vall-Roqué, H. H., Andrés, A., & Saldaña, C. The impact of COVID-19 lockdown on social network sites use, body image disturbances and self-esteem among adolescent and young women Progress in Neuro-Psychopharmacology and Biological Psychiatry 2021 110 110293 Vall-Roqué, H. H., Andrés, A., & Saldaña, C. (2021). The impact of COVID-19 lockdown on social network sites use, body image disturbances and self-esteem among adolescent and young women. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 110, 110293. doi: 10.1016/j.pnpbp.2021.110293
	World Bank. (2020). Obesity: Health and Economic Consequences of an Impending Global Challenge. Washington, DC.
	Trogdon, J. G., Nonnemaker, J., & Pais, J. Peer effects in adolescent overweight Journal of Health Economics 2008 27 5 1388 1399 Trogdon, J. G., Nonnemaker, J., & Pais, J. (2008). Peer effects in adolescent overweight. Journal of Health Economics, 27(5), 1388—1399. doi: 10.1016/j.jhealeco.2008.05.003
	WHO. (2017). The Double Burden of Malnutrition: Policy Brief. Department of Nutrition for Health and Development.
	Zhang, J., Tong, L., Lamberson, P. J., Durazo-Arvizu, R. A., Luke, A., & Shoham, D. A. Leveraging social influence to address overweight and obesity using agent-based models: The role of adolescent social networks Social Science & Medicine 2015 125 203 213 Zhang, J., Tong, L., Lamberson, P. J., Durazo-Arvizu, R. A., Luke, A., & Shoham, D. A. (2015). Leveraging social influence to address overweight and obesity using agent-based models: The role of adolescent social networks. Social Science & Medicine, 125, 203—213.

	班级平均BMI		班级超重肥胖率
	(1)	(2)	(3)	(4)
男生比例	2.973*	2.854**	0.181	0.167*
	(1.148)	(1.043)	(0.094)	(0.084)
农业户口学生比例	?0.594	?0.295	?0.065	?0.033
	(0.450)	(0.486)	(0.043)	(0.042)
平均父母最高受教育年限	0.030	0.114	?0.002	0.005
	(0.088)	(0.092)	(0.008)	(0.008)
平均家庭经济条件	0.475	0.308	0.074*	0.063
	(0.520)	(0.552)	(0.036)	(0.040)
班级规模	?0.018*	?0.011	?0.001*	?0.001
	(0.007)	(0.008)	(0.001)	(0.001)
班级排名	?0.035	?0.048	?0.005	?0.006
	(0.073)	(0.078)	(0.006)	(0.007)
班主任教龄	0.004	0.005	0.001	0.002
	(0.010)	(0.010)	(0.001)	(0.001)
学校层面特征		是		是
样本量	169	169	169	169
VIF均值	2.15	2.22	2.15	2.22

	个体BMI					个体BMI
	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
同伴平均BMI	0.674***	0.637***	0.688***	0.402***	0.400***
同伴平均BMI	(0.033)	(0.041)	(0.044)	(0.053)	(0.054)
同伴超重肥胖率						6.768***	6.279***	6.550***	3.588***	3.557***
同伴超重肥胖率						(0.502)	(0.590)	(0.628)	(0.641)	(0.653)
社会乘数	—	—	—	—	1.667	—	—	—	—	—
个体及家庭特征		是	是	是	是		是	是	是	是
情境效应			是	是	是			是	是	是
关联效应：相关群体				是	是				是	是
关联效应：共同环境					是					是
样本量	6875	6307	630	5725	5725	6875	6307	6307	5725	5725
R²	0.034	0.041	0.042	0.357	0.358	0.030	0.036	0.036	0.354	0.355

	个体BMI				个体BMI
	IV-2SLS	IV-GMM	IV-2SLS	IV-GMM	IV-2SLS	IV-GMM	IV-2SLS	IV-GMM
	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
同伴平均BMI	0.715***	0.719***	0.232**	0.237***
同伴平均BMI	(0.041)	(0.041)	(0.097)	(0.097)
同伴超重肥胖率					8.017***	8.157***	2.883**	2.949**
同伴超重肥胖率					(0.791)	(0.786)	(1.193)	(1.192)
社会乘数	—	—	1.302	1.311	—	—	—	—
第一阶段回归
基线时期同伴平均BMI	0.696***	0.696***	0.566***	0.566***	0.062***	0.062***	0.049***	0.049***
基线时期同伴平均BMI	(0.058)	(0.058)	(0.062)	(0.062)	(0.005)	(0.005)	(0.005)	(0.005)
同伴与祖辈同住比例	?0.065	?0.065	?0.087	?0.087	0.013	0.013	0.028	0.028
同伴与祖辈同住比例	(0.460)	(0.460)	(0.416)	(0.416)	(0.044)	(0.044)	(0.041)	(0.041)
个体及家庭特征	是	是	是	是	是	是	是	是
情境效应			是	是			是	是
关联效应		是	是				是	是
检验结果
内生性检验	6.359	6.359	2.864	2.864	11.093	11.093	0.202	0.202
p值	(0.012)	(0.012)	(0.091)	(0.091)	(0.001)	(0.001)	(0.653)	(0.653)
弱工具变量检验	3008.476	3008.476	1274.871	1274.871	2757.574	2757.574	1123.159	1123.159
过度识别检验	2.291	2.291	1.940	1.940	2.431	2.431	1.200	1.200
p值	(0.130)	(0.130)	(0.164)	(0.164)	(0.119)	(0.119)	(0.273)	(0.273)
样本量	6307	6307	5725	5725	6307	6307	5725	5725

	个体BMI			个体BMI
	(1)	(2)	(3)	(4)	(5)	(6)
同伴平均BMI	0.497***	0.386***	0.474***
同伴平均BMI	(0.064)	(0.064)	(0.064)
同伴超重肥胖率				4.661***	3.305***	4.584***
同伴超重肥胖率				(0.725)	(0.682)	(0.667)
错误感知自身体重	3.768*			0.073
错误感知自身体重	(1.720)			(0.148)
核心解释变量*错误感知自身体重	?0.208*			?2.278*
核心解释变量*错误感知自身体重	(0.089)			(0.900)
高估自身体重		5.711***			0.037
高估自身体重		(1.288)			(0.118)
核心解释变量*高估自身体重		?0.322***			?3.831***
核心解释变量*高估自身体重		(0.067)			(0.706)
低估自身体重			?0.746			0.073
低估自身体重			(3.433)			(0.265)
核心解释变量*低估自身体重			0.051			1.266
核心解释变量*低估自身体重			(0.177)			(1.610)
个体及家庭特征	是	是	是	是	是	是
情境效应	是	是	是	是	是	是
关联效应	是	是	是	是	是	是
样本量	5708	5708	5708	5708	5708	5708
R²	0.360	0.359	0.364	0.357	0.356	0.361

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[2]	Wenming Zhang, Jiasheng Chen. Obesity in Primary and Middle School Students： Inter-school Differences and Time-use Patterns [J]. Journal of East China Normal University(Educational Sciences), 2022, 40(2): 43-56.
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