The Energy Information Administration gathers data on residential energy consumption and expenditures and publishes its findings in "Residential Energy Consumption Survey: Consumption and Expenditures." Suppose that we want to decide whether a difference exists in mean annual energy consumption by households among the four U.S. regions. The data contains last year's energy consumptions for households in the four U.S. regions.

Northeast Midwest South West 15 17 11 10 10 12 7 12 13 BT 9 8 14 13 13 13 15 9 12