The Development Of The Anchoring Effect On Decision Making

Anchoring effect was used to refer to the phenomena of estimation bias that the judgment and decision making result or target value approached excessively to the anchor, i.e. the initial information or initial value. It was a heuristic bias found in exploring decision making behavior and process in the descriptive paradigm of decision making research. The study of anchoring effects was of great significant to understand the negative influence of the heuristic strategy in decision making and seeking effective ways to reduce the decision making bias. Past researches on anchoring effects were mainly focused on uncovering and examining the anchoring effects on the economic field. There were deficiencies on the systematic comparative research on decision making characteristics across different material contents and different types of anchors, as well as the mechanisms and the developmental characteristic of anchoring effects.The present research was designed to examine the differentiation of the developmental characteristics of the judgmental anchoring on external, internal and dual anchors, using two types of materials, empirical knowledge and figure estimate, with subjects of junior, senior high school students and college students.The present research consists of three parts:Study 1 was to examine the decision making characteristics to the anchoring questions of three types of anchors, external, internal and objective internal-external anchors, in the developmental views, with experimental materials of general knowledge, everyday common knowledge and real social occurrences as anchoring questions. Study 1 consists of 5 experiments. Experiment 1 adopted classical two step paradigm to compare the magnitude of the external anchoring effects and the developmental characteristics by manipulating the familiarity of the material and the high-low anchor values, as well as to compare the difference of magnitude of the anchoring effects initiated by high and low anchor values under different familiarity conditions. Experiment 2 adopted the one step paradigm of internal anchoring questions to examine the adjusting magnitude of estimate value from internal anchor and the variation of age characteristics, and to examine the satisfactory principle of the adjustment mechanism. Experiment 3 was based on the combination of the one step paradigm of internal anchoring questions and the classical two step paradigm, with the procedure of "answering internal questions+classical two step paradigm", by manipulating the rationality of the internal anchor to examine the relations between objective internal and external anchors in decision makings, and the differentiation of decision making under dual anchors across different age groups. Experiment 4 used real social events as external anchoring questions, by manipulating the anchor values with or without supporting information to the decision making and the high-low anchor values to examine the magnitude of the external anchoring effect and the characteristics across age groups, and to analyze the influence of the supporting information of the anchor value to the decision making. Experiment 5 used the eye-movement technique, with materials of common knowledge backed by positive or negative information, presenting the background information and the decision making questions in four step overlaying, to examine the eye-movement characteristics of decision making under the positive and negative information supported external anchoring questions, to test and analyze the influence of the anchor value to the decision making process and its mechanism.Study 2 was to examine the decision making characteristics of the figure estimation in external, internal and objective internal-external anchors from the developmental point of view, with random scattered star figures as experiment material. It consists of 3 experiments. Experiment 1 was designed to examine the magnitude of external anchoring effect and its developmental characteristics with experimental procedure of "target figure presentation+classical two step paradigm". Experiment 2 was designed to examine the decision making value adjustment range from the internal anchor and the differences across age groups, and further to examine the satisfactory principle in decision making, with experimental procedure of "internal anchor figure learning+target figure presentation+one step internal anchor". Experiment 3 was designed to examine the combined influence of objective internal and external anchors to decision making, the relations between the internal and external anchors, and the developmental characteristics, by manipulating the rationality of the internal anchor with the experimental procedure of "internal anchor learning+target figure presentation+classical two step paradigm".Study 3 was to examine the influence of time pressure and processing fluency to the anchoring effects with general knowledge questions and common judgment questions. It consists of 2 experiments. Experiment 1 was designed to examine the characteristics and differences of anchoring effects in the conditions of with or without time pressure under three types of anchors, internal, external and dual anchors, by manipulating variance of time pressure. Experiment 2 was designed to examine the characteristics and differences of anchoring effects, as well as the influence of metacognitive difficulty to the external anchoring effect in the conditions of processing fluency and non-fluency, by manipulating font style and grayscale of the common judgment anchoring questions.The research found that:(1)Empirical knowledge questions could easily activate the empirical system and heuristic strategy in decision making as it closely related to common everyday knowledge, therefore, it generated greater degree of anchoring bias. The physical attributes and the estimation tasks of the figure materials could arouse the perceptive and logical reasoning abilities of the decision maker, and strengthen the analytical process in decision making. And the presentation of questions provides the available real sources. All of these partly weakened the anchoring effects.(2)External anchor aroused greater bias than other anchors, and there were no differences between age groups. Both internal and dual anchor effects had the tendency of fading with the increase of the age. It indicated that in the anchoring questions of various types, more components of effortful thinking initiated, more extent of analytical process getting involved. Therefore, the activation of anchoring heuristic would be suppressed to a certain extent.(3)There were two interrelated mechanisms of accessibility and adjustment in decision making process of the dual anchors. The relations of the dual anchors and their predominance depend on the materials and the types of questions, and finally they influence the ultimate decisions.(4)There were age difference in decision making across different materials and different types of anchor values. It appeared the tendency that the size of anchoring effect decreased with the increase of age in adolescence. But it also showed the variation unstability.(5)The anchoring effect was generated by the focus and the process to the anchor value.(6)The dual-process theory could well explain the content effect, type effect and age effect of the anchoring questions and their influential factors.