이 연구는 이용자 정파성에 따른 포털 뉴스와 포털 뉴스 댓글에 대한 지각된 정파성의 차이와 이런 지각의 차이가 포털 뉴스 평가와 이용에 미치는 영향을 살펴보았다. 분석 결과, 보수 성향 이용자는 다음 뉴스와 댓글 의견에 더 강한 적대적 정파성을 지각하는 반면, 진보 성향 이용자는 네이버 뉴스와 댓글에 더 큰　적대적 지각을 하는 것으로 나타났다. 두 포털 뉴스에 대한 지각된 정파성은 해당 포털 뉴스에 대한 신뢰도 평가, 선택과 회피에 영향을 미쳤다. 특히 지각된 정파성의 영향력은 보수 이용자보다 진보 이용자 집단에서 더 크게 나타났다. 포털 뉴스 댓글에 대한 적대적 의견 지각도 두 포털 뉴스에 대한 신뢰, 제삼자 지각, 선택적 노출에 영향을 미쳤으나, 영향력의 크기에 있어서 두 정파 이용자 집단 간에 뚜렷한 차이는 발견되지 않았다. 본 연구의 결과는 정파 매체를 대상으로 발생하는 정파적 이용자의 내외집단(우호적, 적대적) 매체 구분과 그 효과가 뉴스를 직접 생산하지 않고 재매개만 하는 비정파 매체인 포털 뉴스에 대해서도 일어나고 있음을 보여준다. 이와 같은 현상을 일으키는 우리 언론환경과 포털 뉴스 시장의 특수성이 논의되었다.
　
It is peculiar in Korea that most news users heavily rely on two portal sites, Naver and Daum, to obtain and discuss the news. The two portal sites remediate news from other professional news organizations without showing open editorial favoritism toward one partisan media group over the other in the highly partisan media setting of Korea. However, the two portal sites are often criticized for partisan bias and lack of fairness in their gatekeeping, and also partisan users reportedly rely on different sites, with Daum attracting more progressive users than Naver. This study attempts to address the factors that cause bias perceptions toward the seemingly neutral news providers and the effects of those perceptions on portal news evaluations and uses. Based on the theoretical frameworks of hostile media perception and selective exposure, we examine how the perceived partisan slants toward the two portal sites influence evaluation and selective exposure regarding the two sites. We also look at whether the perceived opinion climates of user comments on the two sites exert similar influences on portal news evaluation and use. Given the differential perceptions and use of media between the progressive and conservative in Korea, this study compares the differences in the perceptions and uses of portal news between the two groups. Analyzing an online survey of 1060 Korean adults, the results show that conservative users perceived stronger hostile partisan bias toward news and user comments on Daum, whereas progressive users perceived stronger hostile partisan bias to news and comments offered by Naver. The perceived partisan bias of perceptually in-group (friendly) portal news influenced users’ trust and selective use of portal news more strongly among progressive users than among conservative users. The more partisan slants progressive users perceive from their friendly portal news, they were less likely to trust and use the friendly portal news. The same patterns were not found in conservative users. With respect to perceptually out-group(hostile) portal news, the effects of perceived partisan bias of the hostile portal news sites on trust and third person perception of the portal news were found to be stronger among progressive users than among conservative users. Also, the perceived hostile opinions of user comments from portal news sites were associated with trust, third person perception, and use of those sites, but the partisan group differences were found to be relatively small. In addition, the effect of perceived hostile opinions of user comments from hostile portal news sites on trust in the portal news was stronger among conservative users than among progressive users. The overall results suggest that, in the highly partisan media setting of Korea, partisan users distinguish between in-group(friendly) and out-group(hostile) portal news sites, although these sites only remediate news from other news organizations, and the distinctions affect partisan users" portal news attitudes and uses.