Population Proportion#
2003, Free Response, #5
A random sample of 200 students was selected from a large college in the United States. Each selected student was asked to give his or her opinion about the following statement.
“The most important quality of a person who aspires to be the President of the United States is a knowledge of foreign affairs.”
Each response was recorded in one of five categories. The gender of each selected student was noted. The data are summarized in the table below.
Is there sufficient evidence to indicate that the response is dependent on gender? Provide statistical evidence to support your conclusion.
2009, Free Response Form B, #3
A French study was conducted in the 1990s to compare the effectiveness of using an instrument called a cardiopump with the effectiveness of using traditional cardiopulmonary resuscitation (CPR) in saving lives of heart attack victims. Heart attack patients in participating cities were treated with either a cardiopump or CPR, depending on whether the individual’s heart attack occurred on an even-numbered or an odd-numbered day of the month. Before the start of the study, a coin was tossed to determine which treatment, a cardiopump or CPR, was given on the even-numbered days. The other treatment was given on the odd-numbered days. In total, 754 patients were treated with a cardiopump, and 37 survived at least one year; while 746 patients were treated with CPR, and 15 survived at least one year.
The conditions for inference are satisfied in the study. State the conditions and indicate how they are satisfied.
Perform a statistical test to determine whether the survival rate for patients treated with a cardiopump is significantly higher than the survival rate for patients treated with CPR.
2012, Free Response, #4
A survey organization conducted telephone interviews in December 2008 in which 1,009 randomly selected adults in the United States responded to the following question.
At the present time, do you think television commercials are an effective way to promote a new product?
Of the 1,009 adults surveyed, 676 responded “yes.” In December 2007, 622 of 1,020 randomly selected adults in the United States had responded “yes” to the same question. Do the data provide convincing evidence that the proportion of adults in the United States who would respond “yes” to the question changed from December 2007 to December 2008?