The Perception Of Opportunity Equality Affects Outcome Evaluation:Behavior And ERP Evidence

Social equality is an essential ingredient in human society.Numerous empirical studies have shown that people generally have an unfair aversion tendency and are willing to sacrifice their own interests to maintain fairness.Social equality consists of two dimensions: outcome equality and opportunity equality.However,previous studies on social equality have exclusively focused on the area of outcome equality,especially concerned the effect of outcome equality on outcome evaluation.The only empirical research in opportunity equity area have explored the mechanism of opportunity equality itself in the social non-competitive text;however,it remains unclear whether opportunity equality affects outcome evaluation.Two experimental researches were performed to explore the event-related potential(ERP)responses to the effect of opportunity on outcome evaluation in the social competitive text and social non-competitive text,respectively.In the two studies,the adopted two-person choice game was used.Study 1 investigated the effect of opportunity equality on outcome evaluation in the non-competitive situation,by using the rule “the people who tossed the heads of the coins would get money” in the “two-person toss-a-coin game”.Study 1 included two experiments: experiment 1a and experiment 1b.Experiment 1a measured people’s fairness perception and pleasantness perception on the opportunity number to toss a coin from the behavior level.Based on experiment 1a,experiment 1b defined less opportunity,equal opportunity,and more opportunity as disadvantageous opportunity unequal,opportunity equal,and advantageous opportunity unequal;and further investigated the ERP characters of the three types of opportunity equality during outcome evaluation in competitive situation.On the basis of study 1,study 2 further investigated the behavioral and cognitive mechanisms of opportunity equality during outcome evaluation in the competitive situation,by using the rule “the people who tossed a larger dice score would get money” in the “two-person toss-a-dice game”.These two studies consistently showed that:(1)At the behavioral level,for fairness perception,participants regarded the opportunity as fair when their opportunity number to toss the coin(dice)was the same as the partner,while they regarded the opportunity as unfair when their opportunity number was less or more than the partner;and participants’ fairness ratings for equal opportunity was the highest,the ratings for more opportunity was the lowest,and the ratings for less opportunity was the middle.For pleasantness perception,participants were pleasant when they had equal or more opportunity,while they were unpleasant when they had less opportunity;and participants’ pleasantness ratings for equal and more opportunity were significant higher than the ratings for less opportunity.(2)At the cognitive level,for FRN component,larger FRN amplitudes were elicited by the monetary outcome in the disadvantageous opportunity unequal condition than in the other two conditions.For P300 component,larger P300 amplitudes were elicited by opportunity inequality conditions than by opportunity equality condition when participants receive a win outcome.(3)The FRN amplitudes were significant positively correlated with the fairness and pleasantness feelings elicited in each opportunity condition,while the P3 amplitudes were not significant correlated with the behavior ratings in each opportunity condition.In conclusion,no matter the social context is non-competitive or competitive,(1)People’s preference for opportunity equality was based on themselves’ material interest,and people’s aversion for opportunity inequality only referred to disadvantageous opportunity unequal aversion.(2)The degree of opportunity equity would modulate FRN and P300,which were elicited during outcome evaluation.Notbly,both FRN and P300 could selectively reflect the opportunity equality degree.For FRN,larger FRN amplitudes were elicited in the disadvantageous opportunity unequal condition,suggesting that FRN reflects whether the actual outcome violated opportunity equality expectancy or not during the early stage of outcome evaluation.Moreover,the positive correlations between FRN amplitudes and subjective ratings(fairness ratings and pleasantness ratings)were found,suggesting that FRN was not related to the opportunity equality expectancy,but also related to the pleasantness inducing by the opportunity equality degree.For P300,larger P300 amplitudes were elicited by opportunity inequality conditions when participants faced a win feedback,suggesting that P300 could encode the conflict between social equality norms and self-interest during the early stage of outcome evaluation.