* Chapter 6: Descriptive Statistics using Stata .

* Import data .
insheet using "C:\temp\autism.csv", comma clear

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* Descriptive Summary #1 .
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tab age

tab sicdegp age

summarize vsae, detail

table age, contents(mean vsae min vsae max vsae)

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* Generate Figure 6.1 .
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tsset childid age

xtline vsae if sicdegp == 1, overlay legend(off) title(SICD Group 1)

graph save "C:\temp\figure61_part1.gph", replace

xtline vsae if sicdegp == 2, overlay legend(off) title(SICD Group 2)

graph save "C:\temp\figure61_part2.gph", replace

xtline vsae if sicdegp == 3, overlay legend(off) title(SICD Group 3)

graph save "C:\temp\figure61_part3.gph", replace

graph combine "C:\temp\figure61_part1.gph"  "C:\temp\figure61_part2.gph"  "C:\temp\figure61_part3.gph", cols(3)

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* Generate Figure 6.2 .
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twoway (lowess vsae age if sicdegp == 1) (scatter vsae age if sicdegp == 1), legend(off) xtitle(age) ytitle(vsae) title(SICD Group 1)

graph save "C:\temp\figure62_part1.gph", replace

twoway (lowess vsae age if sicdegp == 2) (scatter vsae age if sicdegp == 2), legend(off) xtitle(age) ytitle(vsae) title(SICD Group 2)

graph save "C:\temp\figure62_part2.gph", replace

twoway (lowess vsae age if sicdegp == 3) (scatter vsae age if sicdegp == 3), legend(off) xtitle(age) ytitle(vsae) title(SICD Group 3)

graph save "C:\temp\figure62_part3.gph", replace

graph combine "C:\temp\figure62_part1.gph"  "C:\temp\figure62_part2.gph"  "C:\temp\figure62_part3.gph", cols(3)