A survey conducted by the Gallup organization in 1999 asked American adults whether they are satisfied with their physical attractiveness or wish they could be more attractive. The survey found that 71% of women and 81% of men responded that they were satisfied with their attractiveness.
a. Could this study have involved random sampling, random assignment, or both? Explain your answer.
b. Produce a (well-labeled) segmented bar graph to display these results.
c. State the relevant null and alternative hypotheses for testing whether these proportions diff er significantly.
d. What additional information do you need in order to conduct a test of these hypotheses?