When independent observers listened to the tapes of the conversation they found that when women were talking to men who thought they were very attractive, the women exhibited more of the behaviours stereotypically associated with attractive people: they talked more animatedly and seemed to be enjoying the chat more. What was happening was that the women conformed to the stereotype the men projected on them. So people really do sense how they are viewed by others and change their behaviour to match this expectation.
Now this experiment just happened to be carried out by manipulating the stereotype of attractiveness but the same rule applies to many different areas of life. Think of any of the standard stereotypes about class, race and nationality. Each of these create expectations in other people's minds, expectations that are difficult for us to avoid playing up to.
via How Other People’s Unspoken Expectations Control Us | PsyBlog.
This is powerful because it shows another mechanism in which people who think negatively or suspiciously of somebody/something affects how that someone acta/reacts towards them. Does this mean I need to expect people would be kind and giving towards me? I don’t know , maybe. Read the whole thing to see how they setup the experiment.