Variables	Definitions	Questions in the Survey
CARE	Care responsibility of the subject, i.e., does the subject have care responsibilities for children, parents, or grandparents?	Do you need to take care of your children? Do you need to take care of your elderly parent(s)? Do you need to take care of your grandparent(s)?
GENDER	Gender of the subject	What is your gender? Male Female
INCOME	Income level of the subject	What is your total household income? less than US$20,000 US$20,000–34,999 US$35,000–49,999 US$50,000–74,999 US$75,000–99,999 US$100,000–149,999 US$150,000 or higher
CONCERN	Concern level of the subject regarding COVID-19; equals one if the subject is very much concerned or concerned and zero otherwise	How concerned are you about the coronavirus (COVID-19) spread in the US right now? •Not concerned at all •Somewhat concerned •Concerned •Very much concerned
USE	The amount of time spent by a subject on any social media account, which is equal to one when the time spent is less than or equal to 1 h, two when the time spent is more than 1 h but less than or equal to 2 h, three when the time spent is more than 2 h but less than or equal to 3 h, and four when more than 3 h. In our analysis, this is equal to one when the usage level is larger than 2 h and zero otherwise.	On a typical day, how much time (minutes) in total do you spend on all the social media accounts you have (e.g., Facebook, Instagram, Snapchat, Twitter, Pinterest, LinkedIn)?
FATIGUE	Social media fatigue level of a subject. The three questions form one single factor. We used the factor scores of these three questions in the survey. (Items adopted from Bright et al., 2015).	Please rate your degree of agreement with the following statements regarding the amount of information available on social media (1 = strongly disagree, 5 = strongly agree). •I am likely to receive too much information when I am searching on social media. •I am frequently overwhelmed by the amount of information available on social media. •The amount of information available on social media makes me tense and overwhelmed.
ENTERTAINMENT, NETWORKING, COLLABORATION	Social media usage purposes of a subject. The nine questions form three factors. We labeled these factors as follows: ENTERTAINMENT, NETWORKING, and COLLABORATION, respectively. We used the factor score of these nine questions in the survey.	Please rate your degree of agreement with the following statements regarding the purpose of using social media (1 = strongly disagree, 5 = strongly agree). (1)to get to know people I would otherwise not meet at college. (2)to get acquainted with people who share my interests. (3)to do something fun (e.g., watch funny videos, read jokes) (4)to share information about the college campus with friends and classmates (5)to maintain close social relationships with friends and classmates at college (6)to collaborate with friends and classmates to create content for academic work (e.g., build presentations, write project reports) (7)to seek entertainment (8)to take a break from study and academic work (9)to access contents created by my friends and classmates at college (e.g., search and/or gather information from others about course assignments, projects)