How to Cite
Peña V. A., & Gómez-Mejía A. (2020). Effect of heuristic anchoring and adjustment, and optimism bias, in stock market forecasts. Revista Finanzas y Política Económica, 11(2), 389-409. Retrieved from


Stock market forecasting is an important and challenging process that influences investment decisions. This paper presents an experimental design that aims to measure the influence of the anchoring and adjustment heuristic and optimism bias in these forecasts. The study was conducted using information from the S&P MILA Pacific Alliance Select financial index; this was presented to 670 students from the cities of Concepción (Chile), Cali (Colombia), and Lima (Peru). Data was collected and presented through an instrument that asked participants to make a forecast judgment of the said financial index, based on the presented graphics, representing a year, a month, a week, and the last closing value of the index. Thus, it was possible to measure the influence of the anchor and adjustment heuristic in order to establish whether the presence of an initial value affected the financial forecast. Similarly, the study sought to determine whether the judgment issued was biased toward an optimistic or pessimistic position, thereby proving the presence of an error or expectation bias, known as optimism bias. The results were analyzed using the least squares method, and the data panel confirmed that the anchoring and adjustment heuristic influences the forecast of the financial index used in the study. Similarly, the presence of optimism bias in the cognitive process of forecasting in finance was inferred.


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1. Aguiar, F. (2004). Teoría de la decisión e incertidumbre: modelos normativos y descriptivos. Empiria:
Revista de Metodología de Ciencias Sociales, (8), 139-160.

2. Amir, E., & Ganzach, Y. (1998). Overreaction and underreaction in analysts’ forecasts. Journal of Economic
Behavior & Organization, 37(3), 333-347.

3. Ariely, D., Loewenstein, G., & Prelec, D. (2003). «Coherent Arbitrariness»: Stable Demand Curves
Without Stable Preferences. The Quarterly Journal of Economics, 118(1), 73-106.

4. Armor, D. A., & Taylor, S. E. (2002). When predictions fail: The dilemma of unrealistic optimism. In
Gilovich, T., Griffin, D. W., & Kahneman, D. (eds.). Heuristics and biases: The psychology of intuitive judgment.
(pp. 334-347). New York: Cambridge University Press.

5. Barber, B. M., & Odean, T. (2001). Boys will be boys: Gender, overconfidence, and common stock investment.
Quarterly Journal of Economics, 116(1), 261-292.

6. Barberis, N., & Thaler, R. (2003). A survey of behavioral finance. Handbook of the Economic of Finance,

7. Ben-David, I., & Hirshleifer, D. (2012). Are investors really reluctant to realize their losses? Trading responses
to past returns and the disposition effect. Review of Financial Studies. 25(8), 2485-2532.

8. Blankenship, K. L., Wegener, D. T., Petty, R. E., Detweiler-Bedell, B., & Macy, C. L. (2008). Elaboration
and consequences of anchored estimates: An attitudinal perspective on numerical anchoring. Journal of
Experimental Social Psychology, 44(6), 1465-1476.

9. Buehler, R., Griffin, D., & Ross, M. (1994). Exploring the «planning fallacy»: Why people underestimate
their task completion times. Journal of Personality and Social Psychology, 67(3), 366-381.

10. Cadet, B., & Chasseigne, G. (2009). Psychologie du jugement et de la décision: Des modèles aux applications.
(A. Editore, Ed.) (1st ed). Paris: De Boeck Universite.

11. Campbell, S. D., & Sharpe, S. A. (2009). Anchoring bias in consensus forecasts and its effect on
market prices. Journal of Financial and Quantitative Analysis, 44(2), 369-390.

12. Caputo, A. (2014). Relevant information, personality traits and anchoring effect. International Journal of
Management and Decision Making, 13(1), 62-76.

13. Cen, L., Hilary, G., & Wei, K. C. J. (2013). The role of anchoring bias in the equity market: Evidence
from analysts’ earnings forecasts and stock returns. Journal of Financial and Quantitative Analysis, 48(1),

14. Chambers, J. R., & Windschitl, P. D. (2004). Biases in Social Comparative Judgments: The Role of
Nonmotivated Factors in Above-Average and Comparative-Optimism Effects. Psychological Bulletin,
130(5), 813-838.

15. Chang, E. C., Lin, T. C., Luo, Y., & Ren, J. (2019). Ex-day returns of stock distributions: An anchoring
explanation. Management Science.

16. Chapman, G. B., & Johnson, E. J. (1999). Anchoring, activation, and the construction of values.
Organizational Behavior and Human Decision Processes, 79(2), 115-153.

17. Chapman, G. B., & Johnson, E. J. (2002). Incorporating the Irrelevant: Anchors in Judgments of Belief
and Value. In Gilovich, T., Griffin, D. W., & Kahneman, D. (eds.). Heuristics and Biases: The Psychology of
Intuitive Judgment (pp. 120-138). New York: Cambridge University Press.

18. Cowles, A., & Jones, H. E. (1937). Some A Posteriori Probabilities in Stock Market Action. Econometrica,
5(3), 280-294.

19. Daniel, K., Hirshleifer, D., & Teoh, S. H. (2002). Investor psychology in capital markets: evidence
and policy implication. Journal of Monetary Economics, 49(1), 139-209.

20. De Bondt, W. F. M., & Thaler, R. (1985). Does the Stock Market Overreact? Journal of Finance, 40(3),

21. Duclos, R. (2014). The psychology of investment behavior: (De)biasing financial decision-making one
graph at a time. Journal of Consumer Psychology, 25(2), 317-325.

22. Ductor, L., & Leiva-Leon, D. (2016). Dynamics of global business cycle interdependence. Journal of
International Economics, 102, 110-127.

23. Einhorn, H. J., & Hogarth, R. M. (1981). Behavioral Decision Theory: Processed of Judgment and Choice.
Annual Review of Psychology, 32, 53-88.

24. Englich, B., & Soder, K. (2009). Moody experts—How mood and expertise influence judgmental anchoring.
Judgment and Decision Making, 4(1), 41-50.

25. Epley, N., & Gilovich, T. (2001). Putting adjustment back in the anchoring and adjustment heuristic:
Differential Processing of Self-Generated and Experimenter-Provided Anchors. Psychological Science,
12(5), 391-396.

26. Epley, N., & Gilovich, T. (2006). The Anchoring-and- Adjustment Heuristic Why the Adjustments.
Psychological Science, 17(4), 311-318.

27. Fama, E. (1997). Market Efficiency, Long-Term Returns, and Behavioral Finance. Journal of Financial
Economics, 49(3), 283-306.

28. Fama, E. F. (1970). Efficient Capital Markets: A Review of Theory and Empirical Work. The Journal of
Finance, 25(2), 383.

29. Festinger, L. (1957). A Theory of Cognitive Dissonance. Stanford University Press.

30. Fisher, K. L., & Statman, M. (2000). Cognitive Biases in Market Forecasts. The Journal of Portfolio
Management, 27(1), 72-81.

31. Forbes, W., Hudson, R., Skerratt, L., & Soufian, M. (2015). Which heuristics can aid financial-decisionmaking?
International Review of Financial Analysis, 42, 199-210.

32. Galinsky, A. D., & Mussweiler, T. (2001). First offers as anchors: The role of perspective-taking
and negotiator focus. Journal of Personality and Social Psychology, 81(4), 657-669.

33. George, T. J., & Hwang, C. Y. (2004). The 52-week high and momentum investing. Journal of Finance,
59(5), 2145-2176.

34. Gigerenzer, G., & Gaissmaier, W. (2011). Heuristic decision making. Annual Review of Psychology, 62(1),

35. Giordani, P., & Söderlind, P. (2006). Is there evidence of pessimism and doubt in subjective distributions?
Implications for the equity premium puzzle. Journal of Economic Dynamics and Control, 30(6), 1027-1043.

36. Griffin, D., & Tversky, A. (1992). The weighing of evidence and the determinats of confidence. Cognitive
Psychology, 24, 411-435.

37. Hastie, R., & Dawes, R. M. (2010). Rational Choice in an Uncertain World: The Psychology of Judgement
and Decision Making. SAGE Publications.

38. Helweg-Larsen, M., & Shepperd, J. A. (2001). Do Moderators of the Optimistic Bias Affect Personal or
Target Risk Estimates? A Review of the Literature. Personality and Social Psychology Review, 5(1), 74-95.

39. Hilary, G., & Hsu, C. (2011). Endogenous overconfidence in managerial forecasts. Journal of Accounting
and Economics, 51(3), 300-313.

40. Hirshleifer, D. (2015). Behavioral Finance. Annual Review of Financial Economics, 7(1), 133-159.

41. Hysenbelli, D., Rubaltelli, E., & Rumiati, R. (2013). Others’ opinions count, but not all of them: anchoring
to ingroup versus outgroup members’ behavior in charitable giving. Judgment and Decision Making, 8(6),

42. Jefferson, A., Bortolotti, L., & Kuzmanovic, B. (2017). What is unrealistic optimism? Consciousness and
Cognition, 50, 3-11.

43. Kahneman, D. (2003). Maps of Bounded Rationality: Psychology for Behavioral Economics. American
Economic Review, 93(5), 1449-1475.

44. Kahneman, D. (2011). Thinking, Fast and Slow. New York: Farrar, Straus and Giroux.

45. Kahneman, D., Knetsch, J. L., & Thaler, R. H. (1991). Anomalies: The endowment effect, loss aversion,
and status quo bias. The Journal of Economic Perspectives, 5(1), 193-206.

46. Kahneman, D., & Riepe, M. W. (1998). Aspects of Investor Psychology. The Journal of Portfolio Management,
24(4), 52-65.

47. Kahneman, D., Slovic, P., & Tversky, A. (1982). Judgement Under Uncertainty: Heuristics and Biases.
Cambridge University Press.

48. Kahneman, D., & Tversky, A. (1973). On the psychology of prediction. Psychological Review, 80(4), 237-

49. Kahneman, D., & Tversky, A. (1979). Prospect Theory: An Analysis of Decision under Risk. Econometrica,
47(2), 263.

50. Kaustia, M., Alho, E., & Puttonen, V. (2008). How Much Does Expertise Reduce Behavioral Biases? The
Case of Anchoring Effects in Stock Return Estimates. Financial Management, 37(3), 391-412.

51. Kendall, M. G., & Hill, A. B. (1953). The analysis of economic time-series-Part I: Prices. Journal of the
Royal Statistical Society Series A, 116(1), 11.

52. Kinari, Y. (2016). Properties of expectation biases: Optimism and overconfidence. Journal of Behavioral
and Experimental Finance, 10(1), 32-49.

53. Krch, D. (2011). Cognitive Processing. In J. S. Kreutzer, J. DeLuca, & B. Caplan (eds.). Encyclopedia of
Clinical Neuropsychology. (p. 627). New York, NY: Springer New York.

54. Langer, E. J. (1975). The illusion of control. Journal of Personality and Social Psychology, 32(2), 311-328.

55. Levin, I. P., Schneider, S. L., & Gaeth, G. J. (1998). All Frames Are Not Created Equal: A Typology and
Critical Analysis of Framing Effects. Organizational Behavior and Human Decision Processes, 76(2), 149-188.

56. Liao, L.-C., Chou, R. Y., & Chiu, B. (2013). Anchoring effect on foreign institutional investors’ momentum
trading behavior: Evidence from the Taiwan stock market. The North American Journal of Economics and
Finance, 26, 72-91.

57. Locke, J. (1796). An Essay Concerning Human Understanding. The Philosophical Review. 3(5), 601-605.

58. Lovallo, D., & Kahneman, D. (2003). Delusions of Success: How Optimism Undermines Executives’
Decisions. Harvard Business Review. 81(7), 56-63, 117.

59. Lucas, R. E. J. (1978). Asset Prices in an Exchange Economy. Econometrica, 46(6), 1429-1445.

60. Lucey, M. E., & O’Connor, F. A. (2016). Mind the gap: Psychological barriers in gold and silver prices.
Finance Research Letters, 17, 135-140.

61. March, J. G. (1978). Bounded Rationality, Ambiguity, and the Engineering of Choice. The Bell Journal of
Economics, 9(2), 587.

62. Marsden, A., Veeraraghavan, M., & Ye, M. (2008). Heuristics of Representativeness, Anchoring and
Adjustment, and Leniency: Impact on Earnings’ Forecasts by Australian Analysts. Quarterly Journal of
Finance & Accounting, 47(2), 83-102.

63. McElroy, T., & Dowd, K. (2007). Susceptibility to anchoring effects: How openness-to-experience influences
responses to anchoring cues. Judgment and Decision Making, 2(1), 48-53.

64. Mintzberg, H., Raisinghani, D., & Theoret, A. (1976). The Structure of «Unstructured» Decision Processes.
Administrative Science Quarterly, 21(2), 246.

65. Montier, J. (2013). Behavioural Investing: A Practitioner’s Guide to Applying Behavioural Finance. Chichester,
England: John Wiley & Sons.

66. Mullainathan, S., & Thaler, R. (2000). Behavioral Economics. the National Bureau of Economic Research
(Vol. 3). Cambridge, MA.

67. Mussweiler, T., Strack, F., & Pfeiffer, T. (2000). Overcoming the Inevitable Anchoring Effect: Considering
the Opposite Compensates for Selective Accessibility. Personality and Social Psychology Bulletin, 26(9),

68. Newell, B. R., & Bröder, A. (2008). Cognitive processes, models and metaphors in decision research.
Judgment and Decision Making, 3(3), 195-204.

69. Northcraft, G. B., & Neale, M. A. (1987). Experts, amateurs, and real estate: An anchoring-and-adjustment
perspective on property pricing decisions. Organizational Behavior and Human Decision Processes, 39(1),

70. Odean, T. (1998). Are Investors Reluctant to Realize Their Losses? The Journal of Finance, 53(5), 1775-

71. Pachur, T., & Bröder, A. (2013). Judgment: a cognitive processing perspective. Wiley Interdisciplinary
Reviews: Cognitive Science, 4(6), 665-681.

72. Plous, S. (1989). Thinking the Unthinkable: The Effects of Anchoring on Likelihood Estimates of Nuclear
War. Journal of Applied Social Psychology, 19(1), 67-91.

73. Pompian, M. M. (2012). Behavioral Finance and Wealth Management : How to Build Optimal Portfolios That
Account for Investor Biases (2.a ed.). Chichester, England: John Wiley & Sons.

74. Puri, M., & Robinson, D. (2007). Optimism and economic choice. Journal of Financial Economics, 86(1),

75. Rau, R. (2011). Market Inefficiency. In Baker, H. K., & Nofsinger, J. R. (eds.). Behavioral Finance: Investors,
Corporations, and Markets (pp. 331-349). Hoboken, New Jersey: John Wiley & Sons.

76. Ricciardi, V. (2008). The Psychology of Risk: The Behavioral Finance Perspective. In Fabozzi, F. J. (ed.).
The Handbook of Finance. Vol. 2. Investment Management and Financial Management. (pp. 85-111). London:
John Wiley & Sons.

77. Ricciardi, V., & Simon, H. K. (2000). What is Behavioral Finance? Business, Education & Technology
Journal, 2(2), 1-9.

78. Ritter, J. R. (2003). Behavioral finance. Pacific-Basin Finance Journal, 11(4), 429-437.

79. S&P Global. (2019). S&P MILA Indices Methodology.

80. Samuelson, W., & Zeckhauser, R. (1988). Status quo bias in decision making. Journal of Risk and Uncertainty,
1(1), 7-59.

81. Schwert, G. W. (2003). Anomalies and Market Efficiency. Handbook of the Economics of Finance, 1, 939-

82. Sharot, T. (2011). The optimism bias. Current Biology, 21(23), R941-R945.

83. Sharot, T., Riccardi, A. M., Raio, C. M., & Phelps, E. A. (2007). Neural mechanisms mediating optimism
bias. Nature, 450(November), 102-105.

84. Shefrin, H., & Statman, M. (2000). Behavioral Portfolio Theory. The Journal of Financial and Quantitative
Analysis, 35(2), 127.

85. Shepperd, J. A., Carroll, P., Grace, J., & Terry, M. (2002). Exploring the Causes of Comparative Optimism.
Psychologica Belgica, 42, 65-98.

86. Shiller, R. J. (2003). From Efficient Markets Theory to Behavioral Finance The 1980s and Excess Volatility.
Journal of Economic Perspectives, 17(1), 83-104.

87. Shin, H., & Park, S. (2018). Do foreign investors mitigate anchoring bias in stock market? Evidence
based on post-earnings announcement drift. Pacific-Basin Finance Journal, 48(December 2016), 224-240.

88. Simon, H. A. (1955). A Behavioral Model of Rational Choice. The Quarterly Journal of Economics, 69(1),

89. Simon, H. A. (1957). Models of man; social and rational. Operations Research (Vol. 5). Oxford, England: Wiley.

90. Simon, H. A. (1972). Theories of Bounded Rationality. In Decision and Organization: A volume in honor
of Jacob Marschak (pp. 161-176). North-Holland Publishing Company.

91. Slovic, P., & Lichtenstein, S. (1971). Comparison of Bayesian and regression approaches to the study
of information processing in judgment. Organizational Behavior and Human Performance, 6(6), 649-744.

92. Slovic, Paul. (1972). Psychological Study of Human Judgment: Implications for Investment Decision Making.
Journal of Finance, 27(4), 779-799.

93. Staněk, R. (2017). Home bias in sport betting : Evidence from Czech betting market. Judgment and Decision
Making, 12(2), 168-172.

94. Thaler, R. (1980). Toward a positive theory of consumer choice. Journal of Economic Behavior and
Organization, 1(1), 39-60.

95. Thaler, R., & Sunstein, C. (2008). Nudge: Improving Decisions about Health, Wealth, and Happiness (revised).
Penguin UK.

96. Thompson, S. C., Armstrong, W., & Thomas, C. (1998). Illusions of Control, Underestimations,
and Accuracy: A Control Heuristic Explanation. Psychological Bulletin, 123(2), 143-161.

97. Tversky, A., & Kahneman, D. (1974). Judgment under Uncertainty: Heuristics and Biases. Science,
185(4157), 1124-1131.

98. Tversky, A., & Kahneman, D. (1981). The framing of decisions and the psychology of choice. Science,
211(4481), 453-458.

99. Tversky, A., & Kahneman, D. (1992). Advances in Prospect Theory: Cumulative Representation of
Uncertainty. Journal of Risk & Uncertainty, 5(4), 297-323.

100. Von Neumann, J., & Morgenstern, O. (1944). Theory of Games and Economic Behavior. Princeton University

101. Wansink, B., Kent, R. J., & Hoch, S. J. (1998). An Anchoring and Adjustment Model of Purchase Quantity
Decisions. Journal of Marketing Research, 35(1), 71.

102. Weinstein, N. D. (1980). Unrealistic optimism about future life events. Journal of Personality and Social
Psychology, 39(5), 806-820.

103. Westerhoff, F. (2003). Anchoring and Psychological Barriers in Foreign Exchange Markets. Journal of
Behavioral Finance, 4(2), 65-70.

104. Wilke, A., & Mata, R. (2012). Cognitive Bias. In Encyclopedia of human behavior (pp. 531-535). London:
Academic Press.

105. Working, H. (1934). A Random-Difference Series for Use in the Analysis of Time Series. Journal of the
American Statistical Association, 29(185), 11-24.
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