Social Desirability and the Willingness to Provide Social Media Accounts in Surveys. The Case of Environmental Attitudes

[EN] This paper contributes to the research on combining public opinion surveys and social media data by a) analyzing the effects of social desirability on the willingness to provide social media account information in surveys, and b) evaluating the congruence of opinions expressed in the survey and on social media. We analyze these questions by considering the willingness to make a sacrifice for the environment, i.e., the willingness to pay higher taxes and higher prices. Our results show that Facebook users who oppose environmental measures are less likely to share their account information in the survey, whereas this effect could not be found among Twitter users. Considering the congruence of opinions expressed in the survey and on Twitter, we find similar tendencies both at the aggregate and the individual level.