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“K23166” — 2015/1/28 — 9:35 — page 77 — #103
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6.6. EXAMPLES 77
> with(newds, plot(age, i1, ylim=c(0,40), type="n", cex.lab=1.2,
cex.axis=1.2))
> with(alcohol, points(age, i1, pch="a"))
> with(alcohol, lines(lowess(age, i1), lty=1, lwd=2))
> with(cocaine, points(age, i1, pch="c"))
> with(cocaine, lines(lowess(age, i1), lty=2, lwd=2))
> with(heroin, points(age, i1, pch="h"))
> with(heroin, lines(lowess(age, i1), lty=3, lwd=2))
> legend(44, 38, legend=c("alcohol", "cocaine", "heroin"), lty=1:3,
cex=1.4, lwd=2, pch=c("a", "c", "h"))
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