Before the Great Recession, job-creating cities in the Sunbelt, like Las Vegas, Phoenix, and Orlando saw their populations, income levels, and housing prices surge. Las Vegas, however, offered something that often eluded these other cities: upward mobility for the working class. For example, hard-working hotel maids were able to prosper during the boom times. According to the Bureau of Labor Statistics, the average hourly rate for hotel maids was $14.25 in Las Vegas, versus $9.25 in Phoenix and $8.84 in Orlando (The Wall Street Journal, July 20, 2009). Suppose the following summary statistics and ANOVA table were produced for α = 0.05 from a sample of hourly wages of 25 hotel maids in each city.
a. At the 5% significance level, do mean hourly rates for hotel maids differ between the three cities?
b. If differences exist, use Tukeyâs method to determine which citiesâ mean hourly rates differ at the 5% significance level.
SUMMARY Groups Count Average Las Vegas 25 13.91 Phoenix 25 8.82 Orlando 25 8.83 Source of Variation df MS p-value Between Groups 430.87 2 215.44 202.90 2.58E-30 Within Groups 76.44 72 1.06 Total 507.31 74
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