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= Stata Predict = = Stata predict =

'''`predict`''' is a post-estimation command that calculates predicted probabilities.
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Once a model has been fit (any of [[Stata/Logistic|logistic]], [[Stata/Logit|logit]], or [[Stata/Regress|OLS]]), use `predict` to predict a positive outcome. To obtain the predicted outcome propensity from a [[Stata/Logistic|logistic]] model, try:
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logistic dependent independent
predict dependent_propensity if e(sample)
. webuse nhanes2

. gen goodhealth = inrange(hlthstat,1,3)

. logistic goodhealth i.agegrp i.sex weight

Logistic regression Number of obs = 10,351
                                                       LR chi2(7) = 1132.40
                                                       Prob > chi2 = 0.0000
Log likelihood = -5056.9403 Pseudo R2 = 0.1007

------------------------------------------------------------------------------
  goodhealth | Odds ratio Std. err. z P>|z| [95% conf. interval]
-------------+----------------------------------------------------------------
      agegrp |
      30–39 | .7793651 .0902187 -2.15 0.031 .6211643 .9778571
      40–49 | .3560292 .0380841 -9.65 0.000 .288691 .4390742
      50–59 | .2226468 .0225284 -14.85 0.000 .1825947 .2714844
      60–69 | .1394634 .0122928 -22.35 0.000 .1173362 .1657633
        70+ | .104361 .010635 -22.18 0.000 .0854664 .1274327
             |
         sex |
     Female | .8600342 .0451549 -2.87 0.004 .7759337 .9532501
      weight | .9929544 .0017037 -4.12 0.000 .9896208 .9962992
       _cons | 21.95965 3.387447 20.03 0.000 16.23009 29.71186
------------------------------------------------------------------------------
Note: _cons estimates baseline odds.

. predict propensity, pr

. mean propensity, over(strata)

Mean estimation Number of obs = 10,351

---------------------------------------------------------------------
                    | Mean Std. err. [95% conf. interval]
--------------------+------------------------------------------------
c.propensity@strata |
                 1 | .7425612 .0069563 .7289254 .756197
                 2 | .7738034 .01002 .7541622 .7934446
                 3 | .7501458 .0071763 .7360789 .7642126
                 4 | .7842088 .0063844 .7716941 .7967236
                 5 | .7810146 .0084046 .76454 .7974892
                 6 | .7666114 .007752 .7514159 .7818069
                 7 | .7350987 .0062277 .7228913 .7473061
                 8 | .7491121 .0075689 .7342755 .7639487
                 9 | .7983793 .0081168 .7824689 .8142897
                10 | .7807851 .008437 .764247 .7973231
                11 | .7720709 .0079622 .7564634 .7876784
                12 | .7804427 .007765 .7652219 .7956636
                13 | .766857 .0072942 .7525591 .781155
                14 | .7760337 .0066241 .7630492 .7890181
                15 | .7515905 .0068979 .7380693 .7651116
                16 | .7879491 .0072613 .7737155 .8021827
                17 | .7700296 .0065947 .7571028 .7829564
                18 | .7512391 .0070538 .7374124 .7650659
                20 | .7732079 .0080411 .7574459 .78897
                21 | .765017 .0091615 .7470587 .7829753
                22 | .7578301 .007664 .7428073 .772853
                23 | .784183 .0073184 .7698376 .7985285
                24 | .7476354 .0065429 .7348101 .7604606
                25 | .7650576 .008138 .7491056 .7810097
                26 | .7680721 .0084251 .7515573 .7845869
                27 | .7783377 .0081194 .7624221 .7942533
                28 | .7741337 .0081387 .7581803 .7900871
                29 | .7287702 .0061495 .7167159 .7408244
                30 | .7629903 .0068803 .7495037 .7764769
                31 | .7853215 .0078016 .7700289 .8006141
                32 | .8055108 .0065239 .7927226 .818299
---------------------------------------------------------------------
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This can also be used to generate out-of-sample predicted propensities.

{{{
. sample 30
(7,246 observations deleted)

. logistic goodhealth i.agegrp i.sex weight
[snip]

. clear

. webuse nhanes2

. predict propensity, pr

. mean propensity, over(strata)

Mean estimation Number of obs = 10,351

---------------------------------------------------------------------
                    | Mean Std. err. [95% conf. interval]
--------------------+------------------------------------------------
c.propensity@strata |
                 1 | .746138 .0069755 .7324646 .7598114
                 2 | .777912 .0100163 .7582781 .797546
                 3 | .7535636 .0071896 .7394706 .7676566
                 4 | .7876387 .0063554 .7751809 .8000965
                 5 | .783574 .0083246 .7672562 .7998919
                 6 | .7702981 .00772 .7551653 .7854308
                 7 | .7386229 .006259 .7263541 .7508918
                 8 | .7525448 .0075756 .7376952 .7673943
                 9 | .8018701 .0080247 .7861401 .8176002
                10 | .7841906 .0084246 .7676768 .8007044
                11 | .7752522 .0079553 .7596582 .7908461
                12 | .783474 .0077902 .7682037 .7987444
                13 | .7702269 .0072267 .7560612 .7843925
                14 | .7799459 .0065436 .7671192 .7927726
                15 | .7551355 .006916 .7415788 .7686922
                16 | .7911832 .0072553 .7769613 .805405
                17 | .7745866 .0065169 .7618122 .787361
                18 | .755422 .0070323 .7416373 .7692067
                20 | .7769737 .0080169 .7612591 .7926883
                21 | .7683972 .0091782 .7504062 .7863882
                22 | .7622266 .00758 .7473683 .777085
                23 | .7876735 .0073226 .7733199 .8020272
                24 | .7515857 .0065253 .7387948 .7643765
                25 | .7694184 .0081019 .7535371 .7852996
                26 | .7710772 .0084184 .7545756 .7875788
                27 | .7820861 .0080883 .7662315 .7979407
                28 | .7769497 .0082211 .7608347 .7930646
                29 | .7323046 .006182 .7201866 .7444226
                30 | .7661599 .0068439 .7527445 .7795753
                31 | .7889444 .00777 .7737137 .8041751
                32 | .8079336 .0065227 .7951478 .8207193
---------------------------------------------------------------------
}}}

To obtain the predicted probabilities of each outcome from a [[Stata/Mlogit|mlogit]] or [[Stata/Ologit|ologit]] model, try:

{{{
. use https://www3.nd.edu/~rwilliam/statafiles/mroz.dta

. ologit lfstatus kidslt6 kidsge6 age educ exper nwifeinc
[snip]

. predict lfstatus_pr1, pr outcome(0)

. predict lfstatus_pr1, pr outcome(1)

. predict lfstatus_pr2, pr outcome(2)
}}}

----



== See also ==

[[https://www.stata.com/manuals/rpredict.pdf|Stata manual for predict]]

Stata predict

predict is a post-estimation command that calculates predicted probabilities.


Usage

To obtain the predicted outcome propensity from a logistic model, try:

. webuse nhanes2

. gen goodhealth = inrange(hlthstat,1,3)

. logistic goodhealth i.agegrp i.sex weight

Logistic regression                                    Number of obs =  10,351
                                                       LR chi2(7)    = 1132.40
                                                       Prob > chi2   =  0.0000
Log likelihood = -5056.9403                            Pseudo R2     =  0.1007

------------------------------------------------------------------------------
  goodhealth | Odds ratio   Std. err.      z    P>|z|     [95% conf. interval]
-------------+----------------------------------------------------------------
      agegrp |
      30–39  |   .7793651   .0902187    -2.15   0.031     .6211643    .9778571
      40–49  |   .3560292   .0380841    -9.65   0.000      .288691    .4390742
      50–59  |   .2226468   .0225284   -14.85   0.000     .1825947    .2714844
      60–69  |   .1394634   .0122928   -22.35   0.000     .1173362    .1657633
        70+  |    .104361    .010635   -22.18   0.000     .0854664    .1274327
             |
         sex |
     Female  |   .8600342   .0451549    -2.87   0.004     .7759337    .9532501
      weight |   .9929544   .0017037    -4.12   0.000     .9896208    .9962992
       _cons |   21.95965   3.387447    20.03   0.000     16.23009    29.71186
------------------------------------------------------------------------------
Note: _cons estimates baseline odds.

. predict propensity, pr

. mean propensity, over(strata)

Mean estimation                                Number of obs = 10,351

---------------------------------------------------------------------
                    |       Mean   Std. err.     [95% conf. interval]
--------------------+------------------------------------------------
c.propensity@strata |
                 1  |   .7425612   .0069563      .7289254     .756197
                 2  |   .7738034     .01002      .7541622    .7934446
                 3  |   .7501458   .0071763      .7360789    .7642126
                 4  |   .7842088   .0063844      .7716941    .7967236
                 5  |   .7810146   .0084046        .76454    .7974892
                 6  |   .7666114    .007752      .7514159    .7818069
                 7  |   .7350987   .0062277      .7228913    .7473061
                 8  |   .7491121   .0075689      .7342755    .7639487
                 9  |   .7983793   .0081168      .7824689    .8142897
                10  |   .7807851    .008437       .764247    .7973231
                11  |   .7720709   .0079622      .7564634    .7876784
                12  |   .7804427    .007765      .7652219    .7956636
                13  |    .766857   .0072942      .7525591     .781155
                14  |   .7760337   .0066241      .7630492    .7890181
                15  |   .7515905   .0068979      .7380693    .7651116
                16  |   .7879491   .0072613      .7737155    .8021827
                17  |   .7700296   .0065947      .7571028    .7829564
                18  |   .7512391   .0070538      .7374124    .7650659
                20  |   .7732079   .0080411      .7574459      .78897
                21  |    .765017   .0091615      .7470587    .7829753
                22  |   .7578301    .007664      .7428073     .772853
                23  |    .784183   .0073184      .7698376    .7985285
                24  |   .7476354   .0065429      .7348101    .7604606
                25  |   .7650576    .008138      .7491056    .7810097
                26  |   .7680721   .0084251      .7515573    .7845869
                27  |   .7783377   .0081194      .7624221    .7942533
                28  |   .7741337   .0081387      .7581803    .7900871
                29  |   .7287702   .0061495      .7167159    .7408244
                30  |   .7629903   .0068803      .7495037    .7764769
                31  |   .7853215   .0078016      .7700289    .8006141
                32  |   .8055108   .0065239      .7927226     .818299
---------------------------------------------------------------------

This can also be used to generate out-of-sample predicted propensities.

. sample 30
(7,246 observations deleted)

. logistic goodhealth i.agegrp i.sex weight
[snip]

. clear

. webuse nhanes2

. predict propensity, pr

. mean propensity, over(strata)

Mean estimation                                Number of obs = 10,351

---------------------------------------------------------------------
                    |       Mean   Std. err.     [95% conf. interval]
--------------------+------------------------------------------------
c.propensity@strata |
                 1  |    .746138   .0069755      .7324646    .7598114
                 2  |    .777912   .0100163      .7582781     .797546
                 3  |   .7535636   .0071896      .7394706    .7676566
                 4  |   .7876387   .0063554      .7751809    .8000965
                 5  |    .783574   .0083246      .7672562    .7998919
                 6  |   .7702981     .00772      .7551653    .7854308
                 7  |   .7386229    .006259      .7263541    .7508918
                 8  |   .7525448   .0075756      .7376952    .7673943
                 9  |   .8018701   .0080247      .7861401    .8176002
                10  |   .7841906   .0084246      .7676768    .8007044
                11  |   .7752522   .0079553      .7596582    .7908461
                12  |    .783474   .0077902      .7682037    .7987444
                13  |   .7702269   .0072267      .7560612    .7843925
                14  |   .7799459   .0065436      .7671192    .7927726
                15  |   .7551355    .006916      .7415788    .7686922
                16  |   .7911832   .0072553      .7769613     .805405
                17  |   .7745866   .0065169      .7618122     .787361
                18  |    .755422   .0070323      .7416373    .7692067
                20  |   .7769737   .0080169      .7612591    .7926883
                21  |   .7683972   .0091782      .7504062    .7863882
                22  |   .7622266     .00758      .7473683     .777085
                23  |   .7876735   .0073226      .7733199    .8020272
                24  |   .7515857   .0065253      .7387948    .7643765
                25  |   .7694184   .0081019      .7535371    .7852996
                26  |   .7710772   .0084184      .7545756    .7875788
                27  |   .7820861   .0080883      .7662315    .7979407
                28  |   .7769497   .0082211      .7608347    .7930646
                29  |   .7323046    .006182      .7201866    .7444226
                30  |   .7661599   .0068439      .7527445    .7795753
                31  |   .7889444     .00777      .7737137    .8041751
                32  |   .8079336   .0065227      .7951478    .8207193
---------------------------------------------------------------------

To obtain the predicted probabilities of each outcome from a mlogit or ologit model, try:

. use https://www3.nd.edu/~rwilliam/statafiles/mroz.dta

. ologit lfstatus kidslt6 kidsge6 age educ exper nwifeinc
[snip]

. predict lfstatus_pr1, pr outcome(0)

. predict lfstatus_pr1, pr outcome(1)

. predict lfstatus_pr2, pr outcome(2)


See also

Stata manual for predict


CategoryRicottone

Stata/Predict (last edited 2025-04-04 02:56:21 by DominicRicottone)