I'm not sure I totally agree with this. Since this is the only field we are working in, we are susceptible to bias, because we are not being exposed to inside workings of other professions, and the fact that we are more likely to remember psychologists that were this way to us (i.e., the availability heuristic/fallacy) The base rate of occurrence of being a "pompous jerk" is important here. It's probably not any higher in this profession versus the general populations.
Perhaps you're right, perhaps the heuristic is at play here. However, in my own personal experience (and generally agreed upon by other psych friends of mine), there is an apparent difference between the psych persona and those of other majors. Psych individuals tend to be really nice people or complete asses - and they seem to accumulate in the latter category in rather large quantities. Of course, the base rate in my case is only reflective of psychology pools at three different universities that I've been affiliated with. My comparison group would be people from classes I've taken that weren't a part of my major and non-psych work environments that I've been exposed to- people seemed to be a nicer lot on the whole.
Second, when one spends all their time researching an area, and becoming the "expert," it can be hard not to get defensive when that view is challenged.....leading to behavior that can be construed as pompous or arrogant.
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