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syntax [anything(name=detail)]
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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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The following explains why Gallons per 100 Mile is a better measurement than
Miles per Gallon. Going from a 10 Miles per Gallon car to a 20 Miles per Gallon
car saves 5 Gallons per 100 Miles when Miles per Gallon increases 10. Going
from a 20 Miles per Gallon car to a 40 Miles per Gallon car *only* saves 2.5 Gallons
per 100 Miles when Miles per Gallon increases 20.
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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
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## Produce an HTML table from regression results
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_coef_table, markdown
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## Produce a table from **estimates table**
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quietly regress fuel weight gear turn
estimates store model1
quietly regress fuel weight gear turn foreign
estimates store model2
estimates table model1 model2, b(%7.4f) stats(N r2_a) star
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estimates table model1 model2, varlabel b(%7.4f) stats(N r2_a) star markdown
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## Produce a table from community-contributed **esttab**
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cap erase esttab_ex.html
eststo clear
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eststo : quietly regress fuel weight gear turn
eststo : quietly regress fuel weight gear turn foreign
esttab using esttab_ex.html, label ///
width(80%) nogaps ///
mtitles("Model 1" "Model 2") ///
title(Regression table using -esttab-)
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~~~~~
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cap erase esttab_ex.html
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The community-contributed **esttab** is available on the Boston College Statistical
Software Components (SSC) archive; see [ssc install](https://www.stata.com/support/ssc-installation/)
for details.