Abstract: The labor market grapples with significant challenges associated with information asymmetry Job seekers heavily rely on diverse channels to obtain essential information，which is crucial in their job search process These channels can be broadly classified into two categories：formal channels，such as employment agencies，job fairs，and advertisements，and informal channels，including referrals from acquaintances and social networks Extant researches indicate that job seekers often favor informal channels due to their cost advantages However，with the rapid advancement and widespread accessibility of Internet technology in the digital era，online searches have emerged as a new and costeffective channel for information acquisition Hence，it is imperative to investigate the extent to which the structural changes in search costs，attributed to internet usage，influence job seekers preference for informal channels and whether Internetbased job searching offers a more effective means of mitigating information asymmetry compared to informal channels
This paper，focusing on information asymmetry，categorizes the information influencing job search channel selection into three dimensions：basic job information，job seeker capabilities，and job deeplevel information By analyzing data from the Chinese General Social Survey and the China Migrants Dynamic Survey，it examines the impact of Internet usage on job seekers preference for informal channels The findings suggest that while Internet usage generally facilitates the substitution of online channels for informal ones in job search，informal channels remain the predominant mode of job searching Further analysis reveals that this substitution effect and its limitations primarily stem from two factors：first，online channels provide cost advantages in offering basic job information，such as pay levels，resulting in significantly higher hourly wages compared to informal channels However，online channels still struggle to address information asymmetry regarding job seeker capabilities and the job environment，thereby limiting the scope of this substitution effect Consequently，only job seekers with higher education，indicating strong capabilities，tend to prefer online channels over informal ones Additionally，job seekers securing employment through online channels demonstrate a greater tendency to switch jobs compared to those utilizing informal channels，indicating relatively poorer searchmatching outcomes Thus，while online channels exhibit a substitution effect for informal channels，their impact remains limited 
This paper contributes to three key aspects：Firstly，it examines the role of Internet usage in job search scenarios，thereby enriching empirical research on the impact of internet usage on the labor market Secondly，it distinguishes between various dimensions of information asymmetry while elucidating the presence and limitations of substitution effects within this framework Finally，this research enhances the understanding of digital technologys impact on the labor markets overall efficiency Based on the conclusions of this paper，online channels exhibit a significant substitution effect on informal channels，indicating that the use of the Internet has，to some extent，mitigated the information cost disadvantage of traditional formal channels and enhanced the overall operating efficiency of the labor market

Key words: job search, asymmetric information, Internet use, informal channel, online channel

摘要： 本文基于中国综合社会调查和中国流动人口动态监测调查数据，研究了互联网使用对求职者工作搜寻渠道选择的影响。研究发现，互联网使用总体上促成了网络渠道对熟人推荐这一非正式渠道的替代，但后者仍是更为主要的工作搜寻方式。进一步的分析表明，这种替代效应的存在与有限性来源于两方面。一方面，互联网渠道在工薪水平等职位基本信息维度上更具优势，通过网络渠道获取的工作，其小时工资显著高于非正式渠道。另一方面，网络渠道无法有效解决求职者能力信息及岗位深层次信息的信息不对称问题。所以，只有拥有高学历这一强能力信号的求职者更倾向于利用网络渠道取代非正式渠道；相比于非正式渠道，通过网络渠道获得工作的求职者会有更强烈的换工作意愿，反映出相对更差的搜寻匹配效果。

关键词: 工作搜寻, 信息不对称, 互联网使用, 非正式渠道, 网络渠道