What is it called when you notice things are more common when you have one eg a type of car you own appears more common around town since you own it?

Answer 1

I believe this can be classed as a type of cognitive bias. I think the one that most likely explains what is happening here is the "availability heuristic" where the "vividness and emotional impact" of a particular issue (i.e. you just got a new car which is usually a pretty exciting and emotionally charged event) biases your mind to giving it more weight than it actually deserves. Before you owned that car, there was no particular reason (unless we are talking about a particularly exotic one, such as a Lamborghini) for you to give it any more attention than any other run-of-the-mill car. But now that you own one, you see it everywhere because of the emotionally charged state of your mind / perception with respect to this car. For more information on cognitive psychology see here: http://www.answers.com/topic/cognitive-psychology