help lincom dialog: lincom
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Title
[R] lincom -- Linear combinations of estimators
Syntax
lincom exp [, options]
options description
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eform generic label; exp(b); the default
or odds ratio
hr hazard ratio
shr subhazard ratio
irr incidence-rate ratio
rrr relative-risk ratio
level(#) set confidence level; default is level(95)
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where exp is any linear combination of coefficients that is valid syntax
for test; see [R] test. exp must not contain an equal sign.
Menu
Statistics > Postestimation > Linear combinations of estimates
Description
lincom computes point estimates, standard errors, t or z statistics,
p-values, and confidence intervals for linear combinations of
coefficients after any estimation command. Results can optionally be
displayed as odds ratios, hazard ratios, incidence-rate ratios, or
relative-risk ratios.
lincom can be used with svy estimation results; see [SVY] svy
postestimation.
Options
eform, or, hr, shr, irr, and rrr all report coefficient estimates as
exp(b) rather than b. Standard errors and confidence intervals are
similarly transformed. or is the default after logistic. The only
difference in these options is how the output is labeled.
Option Label Explanation Example commands
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eform exp(b) Generic label
or Odds Ratio Odds ratio logistic, logit
hr Haz. Ratio Hazard ratio stcox, streg
shr SHR Subhazard ratio stcrreg
irr IRR Incidence-rate ratio poisson
rrr RRR Relative rate ratio mlogit
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exp may not contain any additive constants when you use the eform,
or, hr, irr, or rrr option.
level(#) specifies the confidence level, as a percentage, for confidence
intervals. The default is level(95) or as set by set level.
Examples
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. webuse regress
. regress y x1 x2 x3
. lincom x2-x1
. lincom 3*x1 + 500*x3
. lincom 3*x1 + 500*x3 - 12
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. webuse lbw
. logit low age lwt i.race smoke ptl ht ui
. lincom 2.race+smoke, or
. logistic low age lwt i.race smoke ptl ht ui
. lincom 2.race+smoke
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. webuse sysdsn1
. mlogit insure age male nonwhite i.site
. lincom [Prepaid]male + [Prepaid]nonwhite
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Saved results
lincom saves the following in r():
Scalars
r(estimate) point estimate
r(se) estimate of standard error
r(df) degrees of freedom
Also see
Manual: [R] lincom
Help: [R] nlcom, [R] test, [R] testnl
