Based on the situation presented above in which Paula has a strong belief that alcohol calms her nerves, it can be deduced that the decision made by her is influenced by her expectation. She believes and expects that if she drinks her nerves calm down.
I believe Paula is more influenced with expectations with her decisions. She is expecting to see that drinking will help her relax and calm her nerves. Of course there are many other ways to do this, but this is the point where she is already addicted to alcohol and will say pretty much anything to have some more.
