The output of a solar panel (photovoltaic) system depends on its size. A manufacturer states that the average daily production of its 1.5 kW system is 6.6 kilowatt hours (kWh) for Perth conditions. A consumer group monitored this 1.5 kW system in 20 different Perth homes and measured the average daily production by the systems in these homes over a one month period during October. The data is provided here.
(a)
Analyse the consumer group’s data to test if the manufacturer’s claim of an average of 6.6 kWh per day is reasonable. State appropriate hypotheses, assumptions and decision rule at α = 0.10. What conclusions would you report to the consumer group? Hint: You will need to find Descriptive Statistics first.)
(b)
If 48 homes in the central Australian city of Alice Springs had this system installed and similar data was
collected, in order to assess whether average daily production in Alice Springs exceeded 6.6 kWh,
(i)
what would the alternate hypothesis be?
(ii)
What would be the critical value(s) for the test at α = 0.01? Be sure to justify your choice of distribution.
(iii)
State the assumption(s) for the test.
(iv)
If the Alice Springs data was collected on the same day as the Perth data, would these two sets of data be independent? Why?
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