Final answer:
Speakers should ask for a show of hands when the audience is comfortable providing a public commitment without embarrassment. This method provides quick feedback but may not accurately reflect participants' true opinions. Scientific polls are more accurate but need to account for social influences and respondent knowledge.
Step-by-step explanation:
Speakers should ask for a show of hands when they are sure that most listeners will be eager and unembarrassed to make a public commitment. This approach is used to gauge the views of an audience on a particular question in an informal way. It is not intended to embarrass listeners or test their knowledge, and while it might offer some insights, it is not as reliable as scientific polling when it comes to gathering statistical data.
Considering the examples given, like a local radio station gauging the preferences of its listeners, or assessing whether students fear public speaking, asking for a show of hands can provide immediate, albeit rough, feedback. However, this method is susceptible to social pressure and may not reflect the true opinions of respondents if they feel uncomfortable openly expressing their views.
Scientific polls, which use random and representative samples, have lower margins of error and are designed by statisticians and social scientists. These types of polls can provide a more accurate picture of public opinion but must still account for factors like social pressure and respondents' knowledge on the topic.