Stata Margins
The margins command reports expected values from a model.
Contents
Usage
Adapted from here:
. webuse nhanes2l
(Second National Health and Nutrition Examination Survey)
. regress bpsystol i.hlthstat##i.diabetes
Source | SS df MS Number of obs = 10,335
-------------+---------------------------------- F(9, 10325) = 86.92
Model | 396524.045 9 44058.2272 Prob > F = 0.0000
Residual | 5233449.31 10,325 506.871604 R-squared = 0.0704
-------------+---------------------------------- Adj R-squared = 0.0696
Total | 5629973.35 10,334 544.800982 Root MSE = 22.514
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bpsystol | Coefficient Std. err. t P>|t| [95% conf. interval]
--------------------+----------------------------------------------------------------
hlthstat |
Very good | 2.636051 .6417076 4.11 0.000 1.37818 3.893922
Good | 7.648725 .6272209 12.19 0.000 6.419251 8.8782
Fair | 13.50647 .7408272 18.23 0.000 12.0543 14.95863
Poor | 14.77223 1.032484 14.31 0.000 12.74837 16.7961
|
diabetes |
Diabetic | 5.780232 4.618696 1.25 0.211 -3.273308 14.83377
|
hlthstat#diabetes |
Very good#Diabetic | 17.43339 5.726714 3.04 0.002 6.207924 28.65886
Good#Diabetic | 4.023894 5.032308 0.80 0.424 -5.840404 13.88819
Fair#Diabetic | 7.316062 4.97969 1.47 0.142 -2.445096 17.07722
Poor#Diabetic | 3.445358 5.09316 0.68 0.499 -6.538222 13.42894
|
_cons | 124.2614 .4611975 269.43 0.000 123.3574 125.1655
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. margins i.hlthstat#i.diabetes
Adjusted predictions Number of obs = 10,335
Model VCE: OLS
Expression: Linear prediction, predict()
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| Delta-method
| Margin std. err. t P>|t| [95% conf. interval]
------------------------+----------------------------------------------------------------
hlthstat#diabetes |
Excellent#Not diabetic | 124.2614 .4611975 269.43 0.000 123.3574 125.1655
Excellent#Diabetic | 130.0417 4.595612 28.30 0.000 121.0334 139.05
Very good#Not diabetic | 126.8975 .4461899 284.40 0.000 126.0229 127.7721
Very good#Diabetic | 150.1111 3.356161 44.73 0.000 143.5324 156.6898
Good#Not diabetic | 131.9102 .4250916 310.31 0.000 131.0769 132.7434
Good#Diabetic | 141.7143 1.952195 72.59 0.000 137.8876 145.541
Fair#Not diabetic | 137.7679 .5797601 237.63 0.000 136.6315 138.9043
Fair#Diabetic | 150.8642 1.768852 85.29 0.000 147.3969 154.3315
Poor#Not diabetic | 139.0337 .9237528 150.51 0.000 137.2229 140.8444
Poor#Diabetic | 148.2593 1.93768 76.51 0.000 144.461 152.0575
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