Fundamental attribution error
In social psychology, the fundamental attribution error (FAE) [a] is a cognitive attribution bias in which observers underemphasize situational and environmental factors for the behavior of an actor while overemphasizing dispositional or personality factors.[1] In other words, observers tend to overattribute the behaviors of others to their personality (e.g., he is late because he's selfish) and underattribute them to the situation or context (e.g., he is late because he got stuck in traffic). Although personality traits and predispositions are considered to be observable facts in psychology, the fundamental attribution error is an error because it misinterprets their effects.
The group attribution error (GAE) is identical to the fundamental attribution error, where the bias is shown between members of different groups rather than different individuals.[2]
The ultimate attribution error is a derivative of the FAE and GAE relating to the actions of groups, with an additional layer of self-justification relating to whether the action of an individual is representative of the wider group.[3]
Origin
[edit]Etymology
[edit]The phrase was coined by Lee Ross[4] 10 years after an experiment by Edward E. Jones and Victor Harris in 1967.[5] Ross argued in a popular paper that the fundamental attribution error forms the conceptual bedrock for the field of social psychology. Jones wrote that he found Ross's phrase "overly provocative and somewhat misleading", and also joked: "Furthermore, I'm angry that I didn't think of it first."[6] Some psychologists, including Daniel Gilbert, have used the phrase "correspondence bias" for the fundamental attribution error.[6] Other psychologists have argued that the fundamental attribution error and correspondence bias are related but independent phenomena, with the former being a common explanation for the latter.[7]
1967 demonstration study
[edit]Jones and Harris hypothesized, based on the correspondent inference theory, that people would attribute apparently freely chosen behaviors to disposition and apparently chance-directed behaviors to situation. The hypothesis was confounded by the fundamental attribution error.[5]
Subjects in an experiment read essays for and against Fidel Castro. Then they were asked to rate the pro-Castro attitudes of the writers. When the subjects believed that the writers freely chose positions for or against Castro, they would normally rate the people who praised Castro as having a more positive attitude towards Castro. However, contradicting Jones and Harris' initial hypothesis, when the subjects were told that the writers' positions were determined by a coin toss, they still rated writers who spoke in favor of Castro as having, on average, a more positive attitude towards Castro than those who spoke against him. In other words, the subjects were unable to properly see the influence of the situational constraints placed upon the writers; they could not refrain from attributing sincere belief to the writers. The experimental group provided more internal attributions towards the writer.
Criticism
[edit]The hypothesis that people systematically overattribute behavior to traits (at least for other people's behavior) is contested. A 1986 study tested whether subjects over-, under-, or correctly estimated the empirical correlation among behaviors (i.e., traits, see trait theory).[8] They found that estimates of correlations among behaviors correlated strongly with empirically-observed correlations among these behaviors. Subjects were sensitive to even very small correlations, and their confidence in the association tracked how far they were discrepant (i.e., if they knew when they did not know), and was higher for the strongest relations. Subjects also showed awareness of the effect of aggregation over occasions and used reasonable strategies to arrive at decisions. Epstein concluded that "Far from being inveterate trait believers, as has been previously suggested, [subjects'] intuitions paralleled psychometric principles in several important respects when assessing relations between real-life behaviors."[8]
A 2006 meta-analysis found little support for a related bias, the actor–observer asymmetry, in which people attribute their own behavior more to the environment, but others' behavior to individual attributes.[9] The implications for the fundamental attribution error, the author explained, were mixed. He explained that the fundamental attribution error has two versions:
- Observers tend to explain an actor's behavior with dispositional rather than environmental explanations;
- Observers tend to draw conclusions about an actor's stable disposition based on the actor's behavior in a given situation.
The author of the meta-analysis concluded that the existing weight of evidence does not support the first form of the fundamental attribution error, but does not contradict the second.
Explanations
[edit]Several theories predict the fundamental attribution error, and thus both compete to explain it, and can be falsified if it does not occur. Some examples include:
- Just-world fallacy. The belief that people get what they deserve and deserve what they get, the concept of which was first theorized by Melvin J. Lerner in 1977.[10] Attributing failures to dispositional causes rather than situational causes—which are unchangeable and uncontrollable—satisfies our need to believe that the world is fair and that we have control over our lives. We are motivated to see a just world because this reduces our perceived threats,[11][12] gives us a sense of security, helps us find meaning in difficult and unsettling circumstances, and benefits us psychologically.[13] However, the just-world fallacy also results in a tendency for people to blame and disparage victims of an accident or a tragedy, such as rape[14][15] and domestic abuse,[16] to reassure themselves of their insusceptibility to such events. People may even blame the victim's faults in a "past life" to pursue justification for their bad outcome.[17][page needed]
- Salience of the actor. We tend to attribute an observed effect to potential causes that capture our attention. When we observe other people, the person is the primary reference point while the situation is overlooked as if it is nothing but mere background. As such, attributions for others' behavior are more likely to focus on the person we see, not the situational forces acting upon that person that we may not be aware of.[18][19][20] (When we observe ourselves, we are more aware of the forces acting upon us. Such a differential inward versus outward orientation[21] accounts for the actor–observer bias.)
- Lack of effortful adjustment. Sometimes, even though we are aware that the person's behavior is constrained by situational factors, we still commit the fundamental attribution error.[5] This is because we do not take into account behavioral and situational information simultaneously to characterize the dispositions of the actor.[22] Initially, we use the observed behavior to characterize the person by automaticity.[23][24][25][26][27] We need to make deliberate and conscious effort to adjust our inference by considering the situational constraints. Therefore, when situational information is not sufficiently taken into account for adjustment, the uncorrected dispositional inference creates the fundamental attribution error. This would also explain why people commit the fundamental attribution error to a greater degree when they're under cognitive load; i.e. when they have less motivation or energy for processing the situational information.[28]
- Culture. It has been suggested cultural differences occur in attribution error:[29] people from individualistic (Western) cultures are reportedly more prone to the error while people from collectivistic cultures are less prone.[30] Based on cartoon-figure presentations to Japanese and American subjects, it has been suggested that collectivist subjects may be more influenced by information from context (for instance being influenced more by surrounding faces in judging facial expressions[31]). In contrast to American children emphasizing dispositional factors to explain an event, Hindu children from India were also found to rely more on situational factors.[32] Alternatively, individualist subjects may favor processing of focal objects, rather than contexts.[33] Others suggest Western individualism is associated with viewing both oneself and others as independent agents, therefore focusing more on individuals rather than contextual details.[34]
Versus correspondence bias
[edit]The fundamental attribution error is commonly used interchangeably with "correspondence bias" (sometimes called "correspondence inference"), although this phrase refers to a judgment which does not necessarily constitute a bias, which arises when the inference drawn is incorrect, e.g., dispositional inference when the actual cause is situational. However, there has been debate about whether the two terms should be distinguished from each other. Three main differences between these two judgmental processes have been argued:
- They seem to be elicited under different circumstances, as both correspondent dispositional inferences and situational inferences can be elicited spontaneously.[35] Attributional processing, however, seems to only occur when the event is unexpected or conflicting with prior expectations. This notion is supported by a 1994 study, which found that different types of verbs invited different inferences and attributions.[36] Correspondence inferences were invited to a greater degree by interpretative action verbs (such as "to help") than state action or state verbs, thus suggesting that the two are produced under different circumstances.
- Correspondence inferences and causal attributions also differ in automaticity. Inferences can occur spontaneously if the behavior implies a situational or dispositional inference, while causal attributions occur much more slowly.[37]
- It has also been suggested that correspondence inferences and causal attributions are elicited by different mechanisms. It is generally agreed that correspondence inferences are formed by going through several stages. Firstly, the person must interpret the behavior, and then, if there is enough information to do so, add situational information and revise their inference. They may then further adjust their inferences by taking into account dispositional information as well.[28][38] Causal attributions however seem to be formed either by processing visual information using perceptual mechanisms, or by activating knowledge structures (e.g. schemas) or by systematic data analysis and processing.[39] Hence, due to the difference in theoretical structures, correspondence inferences are more strongly related to behavioral interpretation than causal attributions.
Based on the preceding differences between causal attribution and correspondence inference, some researchers argue that the fundamental attribution error should be considered as the tendency to make dispositional rather than situational explanations for behavior, whereas the correspondence bias should be considered as the tendency to draw correspondent dispositional inferences from behavior.[40][41] With such distinct definitions between the two, some cross-cultural studies also found that cultural differences of correspondence bias are not equivalent to those of fundamental attribution error. While the latter has been found to be more prevalent in individualistic cultures than collectivistic cultures, correspondence bias occurs across cultures,[42][43][44] suggesting differences between the two phrases. Further, disposition correspondent inferences made to explain the behavior of nonhuman actors (e.g., robots) do not necessarily constitute an attributional error because there is little meaningful distinction between the interior dispositions and observable actions of machine agents.[45]
Environmental Factors
[edit]The fundamental attribution error is a multifaceted topic with many backgrounds of study. Some studies have looked deeper into the impacts of external environmental factors on this error, these are some of the factors researchers have found:
- Contextual Influences: The context in which automation is used plays a crucial role. Situational factors, such as the presence of guidelines or prior knowledge about the system, can shape responsibility judgments. The more control one believes they have in a situation the more likely they are to attribute responsibility to themselves.[46]
- Cultural Values: Values such as individualism versus collectivism, can lead to different cognitive approaches, which in turn affects how judgements are made.[47] Cultural backgrounds may have an influence on casual attribution, those raised in different cultural contexts could have varying perspectives on the causes of behavior and performance.[48]
- Feedback Mechanisms: When individuals receive feedback on their judgments, it often serves to confirm their initial biases, leading them to continue attributing behaviors of others to internal factors rather than considering situational influences. This feedback process could create a reinforcing loop, where individuals grow more confident in their internal attributions and less likely to incorporate external factors that may offer a more accurate explanation of behavior.[49]
See also
[edit]Cognitive biases
[edit]Notes
[edit]- ^ Also known as correspondence bias or attribution effect.
References
[edit]- ^ Gawronski, Bertram (2007). "Fundamental Attribution Error".
- ^ Bandinelli, Pier Lluca; Palma, Carlo (2012). "Subthreshold thoughts disorder: a continuum with paranoid delusions? The role of attributional heuristic biases in maintaining self-esteem". In Minati, G.; Abram, M.; Pessa, E. (eds.). Methods, Models, Simulations And Approaches Towards A General Theory Of Change. World Scientific Publishing Company Pte Limited. pp. 587–602. doi:10.1142/9789814383332_0042. ISBN 978-981-4383-32-5.
Fundamental attribution error (Ross, 1977 [33]), is the tendency for explanations of other individuals' behaviors to overemphasize the influence of their personality and underemphasize the influence of their situation (see also actor-observer bias). However, this is coupled with the opposite tendency for the self in that explanations for our own behaviors overemphasize the influence of our situation and underemphasize the influence of our own personality. The group attribution error (Allison and Messick, 1985 [1]) is a group-serving, attributional bias identical to the fundamental attribution error except that it occurs between members of different groups rather than different individuals. Group members are more likely to attribute a fellow group member's actions to their arbitrary circumstances, while attributing a non-group member's actions to something in that group's inherent disposition.
- ^ Bandinelli, Pier Lluca; Palma, Carlo (2012). "Subthreshold thoughts disorder: a continuum with paranoid delusions? The role of attributional heuristic biases in maintaining self-esteem". In Minati, G.; Abram, M.; Pessa, E. (eds.). Methods, Models, Simulations And Approaches Towards A General Theory Of Change. World Scientific Publishing Company Pte Limited. pp. 587–602. doi:10.1142/9789814383332_0042. ISBN 978-981-4383-32-5.
The negativity effect (Regan et al., 1974 [31]; Vonk, 1993 [39]), is an attributional bias that occurs when subjects are asked what they think caused actions of other people whom they dislike. Under these conditions, the positivity effect is reversed and people rate the positive behavior of those they dislike to the situation and their negative behavior to something in their inherent disposition. The negativity effect is sometimes called the ultimate attribution error because of its clear role in racial prejudice. Studies have also found that people assign more weight to negative information in descriptions of others. The positivity effect (Taylor and Koivumaki, 1976 [35]) refers to the tendency for people to attribute the positive behavior of other people whom they like to their disposition, while attributing negative behavior to their situation. It is thus an attributional bias. The opposite effect is called the negativity effect in which the opposite bias in attribution is found when subjects rate others whom they specifically dislike.
- ^ Ross, L. (1977). "The intuitive psychologist and his shortcomings: Distortions in the attribution process". In Berkowitz, L. (ed.). Advances in experimental social psychology. Vol. 10. New York: Academic Press. pp. 173–220. ISBN 978-0-12-015210-0.
- ^ a b c Jones, E. E.; Harris, V. A. (1967). "The attribution of attitudes". Journal of Experimental Social Psychology. 3 (1): 1–24. doi:10.1016/0022-1031(67)90034-0.
- ^ a b Gilbert, D. T. (1998). "Speeding with Ned: A personal view of the correspondence bias" (PDF). In Darley, J. M.; Cooper, J. (eds.). Attribution and social interaction: The legacy of E. E. Jones (PDF). Washington, DC: APA Press. Archived from the original (PDF) on 2011-07-09.
- ^ Gawronski, Bertram (2004). "Theory-based bias correction in dispositional inference: The fundamental attribution error is dead, long live the correspondence bias" (PDF). European Review of Social Psychology. 15 (1): 183–217. doi:10.1080/10463280440000026. S2CID 39233496. Archived from the original on 2016-06-01.
- ^ a b Epstein, Seymour; Teraspulsky, Laurie (1986). "Perception of cross-situational consistency". Journal of Personality and Social Psychology. 50 (6): 1152–1160. doi:10.1037/0022-3514.50.6.1152. PMID 3723332.
- ^ Malle, Bertram F. (2006). "The actor-observer asymmetry in attribution: A (surprising) meta-analysis". Psychological Bulletin. 132 (6): 895–919. doi:10.1037/0033-2909.132.6.895. ISSN 1939-1455. PMID 17073526.
- ^ Lerner, M. J.; Miller, D. T. (1977). "Just-world research and the attribution process: Looking back and ahead". Psychological Bulletin. 85 (5): 1030–1051. doi:10.1037/0033-2909.85.5.1030.
- ^ Burger, J. M. (1981). "Motivational biases in the attribution of responsibility for an accident: A meta-analysis of the defensive-attribution hypothesis". Psychological Bulletin. 90 (3): 496–512. doi:10.1037/0033-2909.90.3.496. S2CID 51912839.
- ^ Walster, E (1966). "Assignment of responsibility for an accident". Journal of Personality and Social Psychology. 3 (1): 73–79. doi:10.1037/h0022733. PMID 5902079. S2CID 26708943.
- ^ Gilbert, D. T.; Malone, P. S. (1995). "The correspondence bias" (PDF). Psychological Bulletin. 117 (1): 21–38. doi:10.1037/0033-2909.117.1.21. PMID 7870861. Archived from the original (PDF) on 2005-12-11.
- ^ Abrams, D.; Viki, G. T.; Masser, B.; Bohner, G. (2003). "Perceptions of stranger and acquaintance rape: The role of benevolent and hostile sexism in victim blame and rape proclivity". Journal of Personality and Social Psychology. 84 (1): 111–125. doi:10.1037/0022-3514.84.1.111. PMID 12518974. S2CID 45655502.
- ^ Bell, S. T.; Kuriloff, P. J.; Lottes, I. (1994). "Understanding attributions of blame in stranger-rape and date-rape situations: An examinations of gender, race, identification, and students' social perceptions of rape victims". Journal of Applied Social Psychology. 24 (19): 1719–1734. doi:10.1111/j.1559-1816.1994.tb01571.x. S2CID 144894634.
- ^ Summers, G.; Feldman, N. S. (1984). "Blaming the victim versus blaming the perpetrator: An attributional analysis of spouse abuse". Journal of Social and Clinical Psychology. 2 (4): 339–347. doi:10.1521/jscp.1984.2.4.339.
- ^ Woogler, R. J. (1988). Other lives, other selves: A Jungian psychotherapist discovers past lives. New York, Bantam.
- ^ Lassiter, F. D.; Geers, A. L.; Munhall, P. J.; Ploutz-Snyder, R. J.; Breitenbecher, D. L. (2002). "Illusory causation: Why it occurs". Psychological Science. 13 (4): 299–305. doi:10.1111/j.0956-7976.2002..x. PMID 12137131. S2CID 1807297.
- ^ Robinson, J.; McArthur, L. Z. (1982). "Impact of salient vocal qualities on causal attribution for a speaker's behavior". Journal of Personality and Social Psychology. 43 (2): 236–247. doi:10.1037/0022-3514.43.2.236.
- ^ Smith, E. R.; Miller, F. D. (1979). "Salience and the cognitive appraisal in emotion". Journal of Personality and Social Psychology. 48 (4): 813–838. doi:10.1037/0022-3514.48.4.813. PMID 3886875.
- ^ Storms, M. D. (1973). "Videotape and the attribution process: Reversing actors' and observers' points of view". Journal of Personality and Social Psychology. 27 (2): 165–175. doi:10.1037/h0034782. PMID 4723963. S2CID 17120868.
- ^ Gilbert, D. T. (2002). Inferential correction. In T. Gilovich, D. W. Griffin, & D. Kahneman (Eds.), Heuristics and biases: The psychology of intuitive judgment. Cambridge University Press.
- ^ Carlston, D. E.; Skowronski, J. J. (1994). "Savings in the relearning of trait information as evidence for spontaneous inference generation". Journal of Personality and Social Psychology. 66 (5): 840–880. doi:10.1037/0022-3514.66.5.840.
- ^ Moskowitz, G. B. (1993). "Individual differences in social categorization: The influence of personal need for structure on spontaneous trait inferences". Journal of Personality and Social Psychology. 65: 132–142. doi:10.1037/0022-3514.65.1.132.
- ^ Newman, L. S. (1993). "How individuals interpret behavior: Idiocentrism and spontaneous trait inference". Social Cognition. 11 (2): 243–269. doi:10.1521/soco.1993.11.2.243.
- ^ Uleman, J. S. (1987). "Consciousness and control: The case of spontaneous trait inferences". Personality and Social Psychology Bulletin. 13 (3): 337–354. doi:10.1177/0146167287133004. S2CID 145734862.
- ^ Winter, L.; Uleman, J. S. (1984). "When are social judgements made? Evidence for the spontaneousness of trait inferences". Journal of Personality and Social Psychology. 47 (2): 237–252. doi:10.1037/0022-3514.47.2.237. PMID 6481615. S2CID 9307725.
- ^ a b Gilbert, D. T. (1989). Thinking lightly about others: Automatic components of the social inference process. In J. S. Uleman & J. A. Bargh (Eds.), Unintended thought (pp. 189–211). New York, Guilford Press.
- ^ Lagdridge, Darren; Trevor Butt (September 2004). "The fundamental attribution error: A phenomenological critique". British Journal of Social Psychology. 43 (3): 357–369. doi:10.1348/0144666042037962. PMID 15479535.
- ^ Miller, J. G. (1984). "Culture and the development of everyday social explanation" (PDF). Journal of Personality and Social Psychology. 46 (5): 961–978. doi:10.1037/0022-3514.46.5.961. PMID 6737211. Archived from the original (PDF) on 2021-09-25. Retrieved 2019-09-24.
- ^ Masuda, T.; Ellsworth, P. C.; Mesquita, B.; Leu, J.; Tanida, S.; van de Veerdonk, E. (2008). "Placing the face in context: Cultural differences in the perception of facial emotion". Journal of Personality and Social Psychology. 94 (3): 365–381. doi:10.1037/0022-3514.94.3.365. PMID 18284287.
- ^ "Fundamental Attribution Error Theory in Psychology". 2023-06-15. Retrieved 2024-10-26.
- ^ Masuda, T.; Nisbett, R. E. (2001). "Attending holistically vs. analytically: Comparing the context sensitivity of Japanese and Americans". Journal of Personality and Social Psychology. 81 (5): 922–934. doi:10.1037/0022-3514.81.5.922. PMID 11708567. S2CID 8850771.
- ^ Markus, H. R.; Kitayama, S. (1991). "Culture and the self: Implications for cognition, emotion, and motivation". Psychological Review. 98 (2): 224–253. CiteSeerX 10.1.1.320.1159. doi:10.1037/0033-295X.98.2.224.
- ^ Hamilton, D. L. (1988). Causal attributions viewed from an information-processing perspective. In D. Bar-Tal & A. W. Kruglanski (Eds.) The social psychology of knowledge. (Pp. 369-385.) Cambridge, England, Cambridge University Press.
- ^ Semin, G. R.; Marsman, J. G. (1994). "Multiple inference-inviting properties" of interpersonal verbs: Event instigation, dispositional inference and implicit causality". Journal of Personality and Social Psychology. 67 (5): 836–849. doi:10.1037/0022-3514.67.5.836.
- ^ Smith, E. R.; Miller, F. D. (1983). "Mediation among attributional inferences and comprehension processes: Initial findings and a general method". Journal of Personality and Social Psychology. 44 (3): 492–505. doi:10.1037/0022-3514.44.3.492.
- ^ Krull, D. S.; Dill, J. C. (1996). "Thinking first and responding fast: Flexibility in social inference processes". Personality and Social Psychology Bulletin. 22 (9): 949–959. doi:10.1177/0146167296229008. S2CID 144727564.
- ^ Anderson, C. A., Krull, D. S., & Weiner, B. (1996). Explanations: Processes and consequences. In E. T. Higgins & A. W. Kruglanski (Eds.), Social psychology: Handbook of basic principles (pp. 221–296). New York, Guilford.
- ^ Hamilton, D. L. (1998). Dispositional and attributional inferences in person perception. In J. M. Darley & J. Cooper (Eds.), Attribution and social interaction (pp. 99-114). Washington, DC, American Psychological Association.
- ^ Krull, Douglas S. (2001). "On partitioning the fundamental attribution error: Dispositionalism and the correspondence bias". In Moskowitz, Gordon B. (ed.). Cognitive Social Psychology: The Princeton Symposium on the Legacy and Future of Social Cognition. Mahwah, New Jersey, USA: Psychology Press. pp. 211–227. ISBN 978-1135664251.
- ^ Masuda, T., & Kitayama, S. (1996). Culture-specificity of correspondence bias: Dispositional inference in Japan. Paper presented at the 13th Congress of the International Association for Cross-Cultural Psychology, Montreal, Quebec, Canada.
- ^ Choi, I.; Nisbett, R. E. (1998). "Situational salience and cultural differences in the correspondence bias and actor-observer bias" (PDF). Personality and Social Psychology Bulletin. 24 (9): 949–960. doi:10.1177/0146167298249003. hdl:2027.42/68364. S2CID 145811653.
- ^ Krull, D. S.; Loy, M. H.; Lin, J.; Wang, C. F.; Chen, S.; Zhao, X. (1999). "The fundamental attribution error: Correspondence bias in individualist and collectivist cultures". Personality and Social Psychology Bulletin. 25 (10): 1208–1219. doi:10.1177/0146167299258003. S2CID 143073366.
- ^ Edwards, Autumn; Edwards, Chad (January 4, 2022). "Does the Correspondence Bias Apply to Social Robots?: Dispositional and Situational Attributions of Human Versus Robot Behavior". Frontiers in Robotics and AI. 8: 404. doi:10.3389/frobt.2021.788242. PMC 8764179. PMID 35059443.
- ^ Douer, Nir; Meyer, Joachim (March 2022). "Judging One's Own or Another Person's Responsibility in Interactions With Automation". Human Factors: The Journal of the Human Factors and Ergonomics Society. 64 (2): 359–371. doi:10.1177/0018720820940516. ISSN 0018-7208. PMC 8943263. PMID 32749166.
- ^ Ma-Kellams, Christine (Jan. 31, 2020). "Cultural Variation and Similarities in Cognitive Thinking Styles Versus Judgment Biases: A Review of Environmental Factors and Evolutionary Forces". Review of General Psychology. 24 (3): 238–253. doi:10.1177/1089268019901270. ISSN 1089-2680.
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(help) - ^ Wang, Hui; Hall, Nathan C. (2018-12-17). "A Systematic Review of Teachers' Causal Attributions: Prevalence, Correlates, and Consequences". Frontiers in Psychology. 9: 2305. doi:10.3389/fpsyg.2018.02305. ISSN 1664-1078. PMC 6304350. PMID 30618897.
- ^ Funder, David C. (1987). "Errors and mistakes: Evaluating the accuracy of social judgment". Psychological Bulletin. 101 (1): 75–90. doi:10.1037/0033-2909.101.1.75. ISSN 0033-2909. PMID 3562704.
Further reading
[edit]- Heider, Fritz. (1958). The Psychology of Interpersonal Relations. New York, John Wiley & Sons. ISBN 0-471-36833-4.
- Gleitman, H., Fridlund, A., & Reisberg D. (1999). Psychology webBOOK: Psychology Fifth Edition / Basic Psychology Fifth Edition. W. W. Norton and Company. Accessed online 18 April 2006.