Gallup found in 2013 that 58% of Americans worry a great deal or a fair amount about global warming, up from 55% in 2012. Results for this Gallup poll were based on telephone interviews conducted March 7-10, 2013, with a random sample of 1022 adults, aged 18 and older, living in the United States. Does the increase from 2012 to 2013 show a significant increase in concern?
a) Write appropriate hypotheses.
b) Check the assumptions and conditions.
c) Perform the test and find the P-value.
d) State your conclusion.
e) Do you think this difference is meaningful? Explain.