via British Psychological Society: Expect better and you shall perceive it.

According to new work in the Journal of Personality and Social Psychology: Interpersonal Relations and Group Processes, in any given week, your perception is tied more to your expectations than to reality. Dr. Samantha Joel at Western University and her colleagues found that people who expected plenty of positive behavior from their partner perceived more of it. Those with low expectations, though, failed to recognize when their partner was making more of an effort.  >>read more via BPS