{smcl} {* *! version 1.1.13 04jun2007}{...} {hline} help for {cmd:confa} postestimation{right:author: {browse "http://stas.kolenikov.name/":Stas Kolenikov}} {right:also see: {help confa}, {help bollenstine}} {hline} {title:Postestimation tools for confa} {pstd}The following commands are available after {help confa}:{p_end} {synoptset 17}{...} {p2coldent :command}description{p_end} {synoptline} {synopt :{helpb confa_estat##fit:estat fitindices}}fit indices{p_end} {synopt :{helpb confa_estat##fit:estat aic}}AIC{p_end} {synopt :{helpb confa_estat##fit:estat bic}}BIC{p_end} {synopt :{helpb confa_estat##corr:estat correlate}}correlations of factors and measurement errors{p_end} {synopt :{helpb confa_estat##predict:predict}}factor scores{p_end} {synoptline} {p2colreset}{...} {title:Special interest postestimation commands} {pstd}These commands provide some additional post-estimation output. {marker corr}{...} {pstd}{opt estat }{cmdab:corr:elate} transforms the covariance parameters into correlations for factor covariances and measurement error covariances. The delta method standard errors are given; for correlations close to plus or minus 1, the confidence intervals may extend beyond the range of admissible values. Additional options are allowed:{p_end} {phang2}{cmd:level(}{it:#}{cmd:)} specifies the CI level{p_end} {phang2}{cmd:bound} provides an alternative CI based on Fisher's {it:z}-transform (arctanh) of the correlation coefficient. It guarantees that the end points of the interval are in (-1,1) range, which may not produce desirable results for Heywood cases.{p_end} {marker fit}{...} {pstd}{opt estat aic} and {opt estat bic} compute the Akaike and Schwarz Bayesian information criteria. {pstd}{opt estat }{cmdab:fit:indices} computes, prints, and saves into {cmd:r()} results a number of traditional fit indices. The following options of {cmd: estat fitindices} request specific indices: {synoptset 17}{...} {p2coldent :option}fit index{p_end} {synoptline} {synopt :{opt aic}}AIC, Akaike information criteria{p_end} {synopt :{opt bic}}BIC, Schwarz Bayesian information criteria{p_end} {synopt :{opt rmsea}}RMSEA, root mean squared error of approximation{p_end} {synopt :{opt rmsr}}RMSR, root mean square residual{p_end} {synopt :{opt tli}}TLI, Tucker-Lewis index{p_end} {synopt :{opt cfi}}CFI, comparative fit index{p_end} {synopt :{opt _all}}all of the above indices, the default{p_end} {synoptline} {p2colreset}{...} {marker predict}{...} {title:Syntax for predict} {p 8 19 2} {cmd:predict} {dtype} {it:{help newvarlist}} {ifin} [{cmd:,} {it:scoring_method}] {cmd:predict} can be used to create factor scores following {cmd:confa}. The number of variables in {it:newvarlist} must be the same as the number of factors in the model specification; all factors are predicted at once by the relevant matrix formula, anyway. The following methods are supported: {synoptset 17}{...} {p2coldent :option}factor scoring method{p_end} {synoptline} {synopt :{cmdab:reg:ression}}regression, or empirical Bayes, score{p_end} {synopt :{cmdab:emp:iricalbayes}}alias for {cmd:regression}{p_end} {synopt :{cmdab:eb:ayes}}alias for {cmd:regression}{p_end} {synopt :{opt mle}}MLE, or Bartlett score{p_end} {synopt :{cmdab:bart:lett}}MLE, or Bartlett score, alias for {cmd:mle}{p_end} {synoptline} {p2colreset}{...} {marker bs}{...} {title:Bollen-Stine bootstrap} {phang}{cmd:bollenstine, }{cmdab:r:eps(}{it:#}{cmd:) } {cmdab:sav:ing(}{it:filename}{cmd:) } {cmdab:confaopt:ions(...) } {it:bootstrap_options} {p_end} {p}{cmd:bollenstine} performs Bollen and Stine (1992) bootstrap. The original data are rotated to conform to the fitted structure. By default, {cmd:bollenstine} re-estimates the model with rotated data, and uses the estimates as starting values in each bootstrap iterations. It also rejects samples where convergence was not achieved (implemented through {cmd:reject( e(converged) == 0)} option supplied to {helpb bootstrap}). {p}The following options are supported: {phang}{cmdab:r:eps(}{it:#}{cmd:)} specifies the number of bootstrap replications. The default is 200.{p_end} {phang}{cmdab:sav:ing(}{it:filename}{cmd:)} specifies the file where the simulation results (the parameter estimates and the fit statistics) are to be stored. The default is a temporary file that will be deleted as soon as {cmd:bollenstine} finishes.{p_end} {phang}{cmdab:confaopt:ions(...)} allows to transfer options to {helpb confa}. Some bootstrap replications produce non-convergent samples that may never converge, so in order to speed up computations, it might make sense to limit the number of iterations, say with {cmd:confaoptions( iter(20) )}.{p_end} {phang}{bf}All non-standard model options, like unitvar or correlated, must be specified with bollenstine to produce correct results!{sf} {phang}All other options are assumed to be {it:bootstrap_options} and passed through to {helpb bootstrap}. {title:Example} {phang2}{cmd:. use http://web.missouri.edu/~kolenikovs/stata/hs-cfa.dta, clear}{p_end} {phang2}{cmd:. confa (vis: x1 x2 x3) (text: x4 x5 x6) (math: x7 x8 x9), from(iv) corr(x7:x8)}{p_end} {phang2}{cmd:. estat fit}{p_end} {phang2}{cmd:. estat corr}{p_end} {phang2}{cmd:. estat corr, bound}{p_end} {phang2}{cmd:. predict fa1-fa3, reg}{p_end} {phang2}{cmd:. predict fb1-fb3, bart}{p_end} {title:Also see} {psee}Online: {helpb confa}, {helpb bollenstine}.{p_end} {title:References} {phang}{bind:}Bollen, K. and Stine, R. (1992) Bootstrapping Goodness of Fit Measures in Structural Equation Models. {it:Sociological Methods and Research}, {bf:21}, 205--229. {p_end} {title:Contact} Stas Kolenikov, kolenikovs {it:at} missouri.edu