You could also have a look at "Rating: how difficult is it?" article, which is not exclusively on dislike behaviour, but it's a comparison of different rating systems, including negative rating.
Sawens, P. (2010) ‘Facebook dislike button: Why it will never happen’, The Next Web URL (consulted August 2014): http://thenextweb.com/socialmedia/2010/10/10/facebook-dislike-button-why-it-will-never-happen/.
Gerlitz, C and Helmond, A. (2013) ‘The Like Economy: Social Buttons and the Data Intensive Web’, Media & Society, pre-peer-reviewed version, URL (consulted October 2014): http://www.annehelmond.nl/wordpress/wp-content/uploads/2013/02/LikeEconomy-PrePeerReview.pdf.
like/dislike user behaviours strongly depends on the category of items under discussion. For example Chang and Sun studied a prediction model of likes of friends' checkins on social network in the following paper:
Location3: How Users Share and Respond to Location-Based Data on Social
Fifth International AAAI Conference on Weblogs and Social Media