I suspect the Dunning Kruger effect is a name for something that happens to most everyone...some more often than others, I guess....
I think madame Palin exhibits traits more like personality disorder of some kind.
Here is something very interesting on Psychopathy (bolded for emphasis, by me):
http://www.sott.net/articles/show/148141-The-Trick-of-the-Psychopath-s-Trade-Make-Us-Believe-that-Evil-Comes-from-Others from a very long interview on the book "Political Ponerology, A science on the nature of evil adjusted for political purposes by Andrzej Łobaczewski"
<snip>
Other recent studies lead to similar results and conclusions: that psychopaths have great difficulty processing verbal and nonverbal affective (emotional) material, that they tend to confuse the emotional significance of events, and most importantly, that these deficits show up in brain scans. Psychopaths exhibit unusual inter-hemispheric distribution of processing resources, have difficulty in appreciating the subtle meanings and nuances of language such as proverbs, metaphors, and so forth, have poor olfactory discrimination, possibly because of orbito-frontal dysfunction, and may have what appears to be a sub-clinical form of thought disorder characterized by a lack of cohesion and coherence in speech. All of these cognitive and affective anomalies cannot be explained by any of the other models of psychopathy, and they can be detected with brain scans.
I've also read other books and articles on Psychopathy and have seen other experts (like Dr Micheal Hare)talk about the coherence and cohesion problems in speech.
Not sure which of the Cluster B disorders she has, but here are diagnostic criteria for the two that seem to fit her best: Anti-Social Personality disorder (Psychopathy) and Narcissistic Personality Disorder.
http://www.behavenet.com/capsules/disorders/prsnltydsrdr.htmDiagnostic criteria for 301.7 Antisocial Personality Disorder
A. There is a pervasive pattern of disregard for and violation of the rights of others occurring since age 15 years, as indicated by three (or more) of the following:
(1) failure to conform to social norms with respect to lawful behaviors as indicated by repeatedly performing acts that are grounds for arrest
(2) deceitfulness, as indicated by repeated lying, use of aliases, or conning others for personal profit or pleasure
(3) impulsivity or failure to plan ahead
(4) irritability and aggressiveness, as indicated by repeated physical fights or assaults
(5) reckless disregard for safety of self or others
(6) consistent irresponsibility, as indicated by repeated failure to sustain consistent work behavior or honor financial obligations
(7) lack of remorse, as indicated by being indifferent to or rationalizing having hurt, mistreated, or stolen from another
Diagnostic criteria for 301.81 Narcissistic Personality Disorder
A pervasive pattern of grandiosity (in fantasy or behavior), need for admiration, and lack of empathy, beginning by early adulthood and present in a variety of contexts, as indicated by five (or more) of the following:
(1) has a grandiose sense of self-importance (e.g., exaggerates achievements and talents, expects to be recognized as superior without commensurate achievements)
(2) is preoccupied with fantasies of unlimited success, power, brilliance, beauty, or ideal love
(3) believes that he or she is "special" and unique and can only be understood by, or should associate with, other special or high-status people (or institutions)
(4) requires excessive admiration
(5) has a sense of entitlement, i.e., unreasonable expectations of especially favorable treatment or automatic compliance with his or her expectations
(6) is interpersonally exploitative, i.e., takes advantage of others to achieve his or her own ends
(7) lacks empathy: is unwilling to recognize or identify with the feelings and needs of others
(8) is often envious of others or believes that others are envious of him or her
(9) shows arrogant, haughty behaviors or attitudes
Added on edit:
website for the book I mention at the top. Wooo, very good (especially if you're a psych. wonk...but even if not, it's still pretty damn good)!
http://www.ponerology.com/psychopaths_3.html