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set linesize 80
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# A fuel consumption study of Stata's auto dataset
We conduct a study of the fuel consumption of cars in Stata's auto dataset.
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sysuse auto, clear
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## Perform data transformation
We generate a variable, **fuel**, that measures the fuel consumption rate in the unit of
Gallons per 100 Miles.
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generate fuel = 100/mpg
label variable fuel "Fuel consumption (Gallons per 100 Miles)"
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## Examine the variables
We examine variables for possible errors in the data.
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describe fuel weight
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assert fuel > 0
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summarize weight
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The variable **weight** has minimum value <>, maximum
value <>, and range <>.
## Plot fuel consumption and vehicle weight
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scatter fuel weight, mcolor(blue%50)
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## Explore relationship between fuel consumption and vehicle weight - linear regression
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regress fuel weight
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matrix define eb = e(b)
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The regression shows that for every unit increase in weight, a
<> unit increase in fuel consumption is predicted.
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The regression shows that for every unit increase in weight, a
<> unit decrease in fuel consumption is predicted.
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