Will a merger strategy increase profits? These questions are answered by some process of judging likelihood. The standard principles used in economic to model probability judgement in economic are concepts of statistical sampling, which are concerned probabilities in the face of new evidence. However, it requires a separation between previously judged probabilities and evaluations of new evidence. However, ( consumers) people often overestimate the probability who previously attached to events which later happened. This leads to "secondguessing". For example, Monday morning quarterbacking and may be partly responsible for lawsuits against stockbrokers who lost money for their clients. ( The clients think the brokers should have known). For example, anybody has tried to learn from a computer distance learning manual has seen the classroom learning of knowledge in action. Another example for making probability judgements is called "representativeness": People judge conditional probabilities like P(hypothesis /data) or P( example/class) by how well the data represents the hypothesis or the example represents the class. Representativeness is an economical shortcut that delivers reasonable judgements with minimal effort in many cases. For example, in judging whether a certain student ( University customer) described in a profile is, say, a psychology major or computer science major, the student decides how well the profile matches the psychology or computer science career to the student generally. So, University can read the student profile to predict whether the student will choose to study psychology subject more prefer or computer subject more prefer to predict whose computer or psychology student numbers more accurate in the year. Many studies show how this sort of feature-matching can lead people to underweigh the "base rate", in this example, the overall frequency of the two majors. Another byproduct of representativeness is the "law of small numbers": Small samples are though to represent the properties of the statistical process that generated them ( as if the law of large numbers, which guarantees that a large sample of independent draws does represent the process, is in a hurry to work). Field and experimental studies with basketball shooting and betting on games that people believe that there is positive attitude that players experience the "hot hand", when there is no evidence that such an effect exists.