Use the following information for the five questions below. A researcher is interested in whether birth order has an effect on the size of a child's vocabulary. A vocabulary test is given to 100 children, all age five and all the oldest in their families. Later, the same vocabulary test is administered to the 100 next oldest sibling of these children when they reach five years of age (so both children in each family take the same test at age five). In this study, the oldest child scored higher on the vocabulary test for 63 of the 100 pairs of children (while the younger child scored higher for 37 of the pairs). A researcher wants to determine if this is strong evidence that order of birth has an effect on vocabulary size, or if these data can be explained by chance. Note that 63 out of 100 is a proportion--so, we are testing the proportion of older children who score higher, The null would be that the proportion of older children who test higher is equal to a 50/50 chance which is what p? The alternative is then that the proportion of older children who test higher differs from this value (i.e. the 'effect' is not defined in terms of whether it is higher or lower) Question 21 What are the null and alternative hypotheses in this situation?

The figure to the right shows the results of a survey in which 1004 adults from Country A, 997 adults from Country B, 999 adults from Country C, 1000 adults from Country D, and 995 adults from Country E were asked whether national identity is strongly tied to birthplace. National Identity and Birthplace People from different countries who believe national identity is strongly tied to birthplace Country A 31% Country B 18% Country C 23% Country D 55% Country E 10% Construct a 95% confidence interval for the population proportion of adults who say national identity is strongly tied to birthplace for each country listed. The 95% confidence interval for the proportion of adults from Country A who say national identity is strongly tied to birthplace is (☐.) - (Round to three decimal places as needed.)

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A report described teens' attitudes about traditional media, such as TV, movies, and newspapers. In a representative sample of American teenage girls, 42% said newspapers were boring. In a representative sample of American teenage boys, 45% said newspapers were boring. Sample sizes were not given in the report. A button hyperlink to the SALT program that reads: Use SALT. (a) Suppose that the percentages reported had been based on a sample of 50 girls and 40 boys. Is there convincing evidence that the proportion of those who think that newspapers are boring is different for teenage girls and boys? Carry out a hypothesis test using ? = 0.05. (Use pgirls − pboys.) Find the test statistic. (Round your answer to two decimal places.) z = Find the P-value. (Round your answer to four decimal places.) P-value = State your conclusion. Reject H0. We do not have convincing evidence that the proportion of girls who say that newspapers are boring is different from the proportion of boys who…