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#
# Verify that scale can be fixed at a value
# coefs will differ slightly due to different iteration paths
tol <- survreg.control()$rel.tolerance
# Intercept only models
fit1 <- survreg(Surv(time,status) ~ 1, lung)
fit2 <- survreg(Surv(time,status) ~ 1, lung, scale=fit1$scale)
all.equal(fit1$coef, fit2$coef, tolerance= tol)
all.equal(fit1$loglik, fit2$loglik, tolerance= tol)
# multiple covariates
fit1 <- survreg(Surv(time,status) ~ age + ph.karno, lung)
fit2 <- survreg(Surv(time,status) ~ age + ph.karno, lung,
scale=fit1$scale)
all.equal(fit1$coef, fit2$coef, tolerance=tol)
all.equal(fit1$loglik[2], fit2$loglik[2], tolerance=tol)
# penalized models
fit1 <- survreg(Surv(time, status) ~ pspline(age), lung)
fit2 <- survreg(Surv(time, status) ~ pspline(age), lung, scale=fit1$scale)
all.equal(fit1$coef, fit2$coef, tolerance=tol)
all.equal(fit1$loglik[2], fit2$loglik[2], tolerance=tol)
rm(fit1, fit2, tol)
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