The New York Times reported that "from 2001 to 2003, World Health Organization surveys measured the prevalence of serious mental disorders in the populations of various countries." A comparison was made between eight developed and seven lessdeveloped countries.

a. Find the mean rate of mental illness for the eight developed countries.

b. Is the mean for the developed countries higher or lower than the mean for the seven less-developed countries, which is 3.0%?

c. To compare rates of mental illness for developed and less-developed countries, is it better to report means or medians? Explain.

d. Explain why the rate of mental illness for all people in the seven less-developed countries combined is not necessarily 3.0%.

e. Find the standard deviation for rate of mental illness in the eight developed countries.

f. Is the standard deviation for the eight developed countries higher or lower than that for the seven less-developed countries, which is 2.1%?

g. The article mentions that "embarrassment about disclosing mental illness varies" from country to country; in some places, like Nigeria, women are reluctant to admit being depressed. Does this result in bias due to a nonrepresentative sample, or bias in the assessment of a variable's values?