Question: Marriage age 2003. The scatterplot suggests a decrease in the difference in ages at first marriage for men and women since 1975. We want to examine the regression to see if this decrease is significant.
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a) Write appropriate hypotheses.
b) Here are the residuals plot and a histogram of the residuals. Do you think the conditions for inference are satisfied? Explain.
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c) Test the hypothesis and state your conclusion about the trend in age at first marriage.