Randomly select a group of people to listen to a speaker's administrative ethics speech to a large group of highly attentive listeners  Then randomly select another group of people to listen to the same content of the speaker's speech to a small group of less attentive listeners
A person's evaluation of the quality of a speaker's speech will be affected by the reaction of others to the speech
 The former group believes that the speaker is thoughtful and confident; The latter group believed that his expression was vague and lengthy