[U] User's Guide

[ U ] 1.3 What’s new 179. Concerning fractional polynomial regression:a. Existing commands fracpoly and mfp have a new syntax. They are now prefix commands,so you type fracpoly, . . .: estimation command and mfp, . . .: estimation command. Oldsyntax continues to be understood.b. Option adjust() used by fracpoly, mfp, and fracgen is renamed center(). The old optioncontinues to be understood.c. fracpoly now works with intreg; see [R] intreg.d. mfp now works with intreg; see [R] intreg.See [R] fracpoly and [R] mfp.10. Concerning the existing estimates command:a. estimates save has new option append, which allows results to be appended to an existingfile. See [R] estimates save.b. estimates use and estimates describe using have new option number(#), which specifiesthe results to be used or described. See [R] estimates save and [R] estimates describe.c. estimates table now supports factor variables and time-series–operated variables and sosupports the new options vsquish, noomitted, baselevels, allbaselevels, and noemptycells;see [R] estimates table.11. Concerning existing estimation command ivregress:a. New postestimation command estat endogenous for use with ivregress 2sls andivregress gmm performs tests of whether endogenous regressors can be treated as exogenous;see [R] ivregress postestimation.b. New option perfect for use with ivregress 2sls and ivregress gmm allows perfectinstruments; it skips checking whether endogenous regressors are collinear with excludedinstruments (see [R] ivregress).12. Concerning regress:a. Existing postestimation command dfbeta now names the variables it creates differently.Variables are now named dfbeta # rather than DFname. The old naming convention isrestored under version control.b. New option notable suppresses display of the coefficient table.See [R] regress.13. Constraints are now allowed by existing estimation commands blogit, bprobit, logistic,logit, ologit, oprobit, and probit. New option collinear specifies not to omit collinearvariables from the model.14. New option nocnsreport for use on estimation commands suppresses display of constraints. See[R] estimation options.15. Existing command pcorr can now calculate semipartial correlation coefficients; see [R] pcorr.16. Existing command pwcorr has new option listwise to omit observations in which any ofthe variables contain missing and thus mimic correlate’s treatment of missing values, whilemaintaining access to all of pwcorr’s other features; see [R] correlate.17. Existing estimation command glm now allows option ml in family(nbinomial ml) to allowestimation via maximum likelihood; see [R] glm.