This study used nationally representative longitudinal data in South Korea to examine how joint changes in adolescents' (N = 7324; M_age ≈ 11 years) cooperative and competitive attitudes from sixth to ninth grade relate to mental health and achievement in 10th grade. The parallel process model showed that both cooperative and competitive attitudes declined over time. Higher cooperative attitudes at baseline indicated higher competitive attitudes, and a faster decline in cooperative attitudes indicated a faster decline in competitive attitudes. The intercept of cooperative attitudes was positively related to mental health but negatively related to achievement. Opposite patterns were found for the intercept of competitive attitudes. These findings highlight the usefulness of considering the co-development of cooperative and competitive attitudes.

中文翻译：

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青少年合作和竞争态度的共同发展：它如何预测心理健康和学业成绩

本研究使用韩国具有全国代表性的纵向数据来检查青少年的关节变化（N  = 7324；M_年龄 ≈ 11 年）从六年级到九年级的合作和竞争态度与十年级的心理健康和成就有关。并行过程模型表明，合作和竞争态度都随着时间的推移而下降。基线较高的合作态度表明竞争态度较高，合作态度下降较快表明竞争态度下降较快。合作态度的截距与心理健康呈正相关，但与成就呈负相关。截取竞争态度时发现了相反的模式。这些发现强调了考虑合作和竞争态度的共同发展的有用性。