Problems 17 and 18 illustrate the use of the sign test to test hypotheses regarding a population proportion. The only requirement for the sign test is that our sample be obtained randomly. When dealing with nominal data, we can identify a characteristic of interest and then determine whether each individual in the sample possesses this characteristic. Under the null hypothesis in the sign test, we expect that half of the data will result in minus signs and half in plus signs. If we let a plus sign indicate the presence of the characteristic (and a minus sign indicate the absence), we expect half of our sample to possess the characteristic while the other half will not. Letting p represent the proportion of the population that possesses the characteristic, our null hypothesis will be H0: p = 0.5. Use the sign test for Problems 17 and 18, following the sign convention indicated previously.
18. Trusting the Press In a study of 2302 U.S. adults surveyed online by Harris Interactive 1243 respondents indicated that they tend to not trust the press. Using an = 0.05 level of significance, does this indicate that more than half of U.S. adults tend to not trust the press?
Step 1 of 5) Trusting the Press In a study of 2302 U.S. adults surveyed online by Harris Interactive 1243 respondents indicated that they tend to not trust the press. Using an = 0.05 level of significance, does this indicate that more than half of U.S. adults tend to not trust the press Why does the level of confidence represent the expected proportion of intervals that contain the parameter if a large number of different samples is obtained How is the margin of error determined In Other Words, The symbol { is read as “plus or minus.” It means “to add and subtract the quantity following the { symbol.”} In Other Words, A confidence interval is a range of numbers, such as 22–30. The level of confidence is the proportion of intervals that will contain the unknown parameter if repeated samples are obtained.
