// Figure 9.1
use "C:\singer willett (2003)\teachers.dta", clear
label define censor 0 "Not censored" 1 "Censored"
label val censor censor
histogram t, by(censor, legend(off) note("")) freq xlabel(1 (1) 12) ylabel(0 (100) 500) ///
addlabels discrete xtitle("Years of teaching") name(figure91, replace)
// Table 10.1
generate event = !censor
qui ltable t event, noadjust saving(lifetable, replace)
preserve
use lifetable, clear
list t0 t1 start deaths lost hazard survival, sep(0) noobs
erase lifetable.dta
restore
// Figure 10.1
stset t, failure(event)
sts generate h = h
twoway scatter h t, msymbol(i) connect(l) ylabel(0 (.05) .15) xlabel(0 (1) 13) ///
sort xtitle("Years in teaching") ///
ytitle("Estimated hazard probability") ///
name(figure101a, replace) nodraw
ltable t event, noadjust notab graph noconf xlabel(0 (1) 13) ylabel(0 (.5) 1) ///
yline(.5) xline(7.6) ///
xtitle("Years in teaching") ///
ytitle("Proportion surviving") ///
name(figure101b, replace) nodraw
graph combine figure101a figure101b, col(1) name(figure101, replace) ysize(8)
// Figure 10.2
use "C:\singer willett (2003)\relapse_days.dta", clear
generate weeks = int(days / 7) + 1
generate event = !censor
stset weeks, failure(event)
sts generate h = h
twoway (scatter h weeks, connect(l) msymbol(i)), xlabel(0 (1) 12) ylabel(, format(%6.2f)) ///
ytitle("Estimated hazard probability") ///
xtitle("Weeks after release") ///
name(figure102a1, replace) nodraw
ltable weeks event, notable graph noconf ylabel(0 (.25) 1, format(%6.2f)) ///
xlabel(0(1)12) yline(0.5) ///
ytitle("Estimated survival probability") ///
xtitle("Weeks after release") ///
name(figure102a2, replace) nodraw
graph combine figure102a1 figure102a2, col(2) ///
title("{bf:A} Time to cocaine relapse", pos(11)) name(figure102a, replace) nodraw
use "C:\singer willett (2003)\firstsex.dta", clear
generate event = !censor
stset time, failure(event)
sts generate h = h
twoway (scatter h time, connect(l) msymbol(i) sort), xlabel(6 (1) 12) ylabel(, format(%6.2f)) ///
ytitle("Estimated hazard probability") ///
xtitle("Grade") ///
name(figure102b1, replace) nodraw
ltable time event, notable graph noconf ylabel(0 (.25) 1, format(%6.2f)) ///
xlabel(6 (1) 12) yline(0.5) ///
ytitle("Estimated survival probability") ///
xtitle("Grade") ///
name(figure102b2, replace) nodraw
graph combine figure102b1 figure102b2, col(2) ///
title("{bf:B} Age at first intercourse for males", pos(11)) name(figure102b, replace) nodraw
use "C:\singer willett (2003)\suicide_orig.dta", clear
generate event = !censor
stset time, failure(event)
sts generate h = h
twoway (scatter h time, connect(l) msymbol(i) sort), xlabel(5 (2) 21) ylabel(, format(%6.2f)) ///
ytitle("Estimated hazard probability") ///
xtitle("Age") ///
name(figure102c1, replace) nodraw
ltable time event, notable graph noconf ylabel(0 (.25) 1, format(%6.2f)) ///
xlabel(5 (2) 21) yline(0.5) ///
ytitle("Estimated survival probability") ///
xtitle("Age") ///
name(figure102c2, replace) nodraw
graph combine figure102c1 figure102c2, col(2) ///
title("{bf:C} Age at first suicide ideation", pos(11)) name(figure102c, replace) nodraw
use "C:\singer willett (2003)\congress_orig.dta", clear
generate event = !censor
stset time, failure(event)
sts generate h = h
twoway (scatter h time, connect(l) msymbol(i) sort), xlabel(0 (1) 8) ylabel(0 (.1) .3, format(%6.2f)) ///
ytitle("Estimated hazard probability") ///
xtitle("Terms in office") ///
name(figure102d1, replace) nodraw
ltable time event, notable graph noconf ylabel(0 (.25) 1, format(%6.2f)) ///
xlabel(0 (1) 8) yline(0.5) ///
ytitle("Estimated survival probability") ///
xtitle("Terms in office") ///
name(figure102d2, replace) nodraw
graph combine figure102d1 figure102d2, col(2) ///
title("{bf:D} Duration of congressional careers for females", pos(11)) name(figure102d, replace) nodraw
graph combine figure102a figure102b figure102c figure102d, row(4) ysize(11) name(figure102, replace)
// Table 10.2
use "C:\singer willett (2003)\teachers.dta", clear
generate event = !censor
qui ltable t event, noadjust saving(lifetable, replace)
preserve
use lifetable, clear
list t0 hazard sehazard survival sesurvival, noobs sep(0)
erase lifetable.dta
restore
// Figure 10.4
use "C:\singer willett (2003)\teachers.dta", clear
list id t censor if inlist(id, 20, 126, 129), noobs sep(0)
expand t
bysort id: generate period = _n // Period identifier
bysort id: generate event = !censor & _n == _N // Calculate outcome for
// discrete-time analysis
list id period event if inlist(id, 20, 126, 129), noobs sepby(id)
// Table 10.3
table period, c(sum event n event mean event)
Reference
Singer, Judith D., and John B. Willett. 2003.
Applied Longitudinal Data Analysis. Modeling Change and Event Occurrence. Oxford University Press. doi: 10.1093/acprof:oso/9780195152968.001.0001
