Concept explainers
The article “Performance Test Conducted for a Gas Air-Conditioning System” (American Society of Heating, Refrigerating, and Air Conditioning Engineering [1969]: 54) reported the following data on maximum outdoor temperature (x) and hours of chiller operation per day (y) for a 3-ton residential gas air-conditioning system:
Suppose that the system is actually a prototype model, and the manufacturer does not wish to produce this model unless the data strongly indicate that when maximum outdoor temperature is 82°F. The true average number of hours of chiller operation is less than 12. The appropriate hypotheses are then
H0: α + β(82) = 12 versus Ha: α + β(82) < 12
Use the statistic
which has a t distribution based on (n – 2) df when H0 is true, to test the hypotheses at significance level 0.01.
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Introduction to Statistics and Data Analysis
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