People consistently overestimate the probability that their offer will be accepted in final offer arbitration. Ignoring the law of small numbers Extrapolating from limited experience leads to errors of judgement. Extreme average values on any metric are much more likely in smaller groups. Confirmatory evidence bias People ignore evidence that contradicts their beliefs. They attempt to confirm their current beliefs, not challenge them.
Expectation influences observation.
This is closely related to the overconfidence bias, by curtailing the search space for solutions. Each side tends to have only one method of negotiating that they assume will work. Cause and effect biases Reordering the sequence in which evidence is viewed affects the causes determined. Fixed-size pie bias People assume that their interests are exact opposites of the other party. They assume they have no common interests, which leads to less than optimal resolution on issues where no incompatibility exists.