Fears of Missing Out (FOMO) is a form of anxiety that arises when someone uses social media. The FOMO scale has three components, namely Sense of Self/Self Esteem, Social Interaction/Extroversion, and Social Anxiety. The purpose of this study is to determine the number of dimensions that precisely measure the FOMO level of social media users. Factor analysis testing conducted on the FOMO Scale is exploratory factor analysis. Exploratory factor analysis is performed to determine the number of components that are most appropriate on the FOMO scale. This study involved 211 respondents who filled out the survey through Google Form. A total of 5 respondents were involved in the process of testing the Indonesian version of the FOMO scale measuring instrument and 2 respondents did not complete the demographic data. Therefore, 204 eligible respondents were used in the analysis process, namely undergraduate students and the frequency of social media checking in a day with an age range of 18-28 iyears. The results of the analysis show that the items on the Fear of Missing Out Scale are grouped into 3 components according to each component definitions.

Identity formation is an adolescent developmental task that continues throughout life. Its process cannot be separated from the role of the significant person for adolescents, including siblings. Therefore, this study aims to examine the identification process (modeling and de-identification) as a mediator in the relationship between sibling relationships in identity formations commitment, in-depth exploration, and reconsideration of commitment.  Four hundred adolescents aged 12-21 years participated in this study. The Indonesian version of the Utrecht-Management of Identity Commitments Scale (U-MICS), the Sibling Relationship Questionnaire (SRQ), and the Sibling Influence Scale (SIS) were used to measure identity formation, sibling relationship quality, and identification process. Data analysis was performed using regression analysis and the Sobel test. The results showed that the identification process could be a mediator between the quality of sibling relationships and identity formation. Also, the differences in quality among siblings lead adolescents to take different paths of the identification process, modeling, or de-identification, which impact the process of identity formation differences.  Adolescents involved in modeling can learn and imitate older siblings to achieve an optimal identity. On the other hand, adolescents involved in de-identification find it more difficult and experience more challenges in achieving an optimal identity