No matter how far in the past a person behaved greedily or immorally, information about her negative behaviors is hardly discounted at all. In contrast, recent positive behaviors are much more influential than behaviors that occurred a long time ago

Brandimarte, L., Vosgerau, J., & Acquisti, A. (2018). Differential discounting and present impact of past information. Journal of Experimental Psychology: General, 147(1), 74-92. http://dx.doi.org/10.1037/xge0000372

Abstract: How does information about a person’s past, accessed now, affect individuals’ impressions of that person? In 2 survey experiments and 2 experiments with actual incentives, we compare whether, when evaluating a person, information about that person’s past greedy or immoral behaviors is discounted similarly to information about her past generous or moral behaviors. We find that, no matter how far in the past a person behaved greedily or immorally, information about her negative behaviors is hardly discounted at all. In contrast, information about her past positive behaviors is discounted heavily: recent behaviors are much more influential than behaviors that occurred a long time ago. The lesser discounting of information about immoral and greedy behaviors is not caused by these behaviors being more influential, memorable, extreme, or attention-grabbing; rather, they are perceived as more diagnostic of a person’s character than past moral or generous behaviors. The phenomenon of differential discounting of past information has particular relevance in the digital age, where information about people’s past is easily retrieved. Our findings have significant implications for theories of impression formation and social information processing.