Marginsplot

[Valerie Herz]

Dear All,
i am still struggling with marginsplot to portray my interaction Terms. I am running the following codes:
// run the regression model xtgls builtlastyear rprov existingboats c.c_rprov##c.c_existingboats standalone GDPgrowth2 leisure olympic texist i.year, panel(hetero) // get plausible/interesting values to plot summarize rprov existingboats margins, dydx(rprov) at(existingboats=(30(5)75)) vsquish // get the adjusted predictions margins, at(rprov=(1 2) existingboats=(30(5)70)) vsquish // plot the predictions marginsplot, noci x(rprov) recast(line) xlabel(30(5)75) But I do get such an Output: Delta-method
dy/dx Std. Err. z P>z [95% Conf. Interval]

rprov
_at
1 . (not estimable)
2 . (not estimable)
3 . (not estimable)
4 . (not estimable)
5 . (not estimable)
6 . (not estimable)
7 . (not estimable)
8 . (not estimable)
9 . (not estimable)
10 . (not estimable)

What does that mean?What am I doing wrong?
Any help would be greatly appreciated!!

[Marcos Almeida]

Welcome to the Stata Forum/ Statalist.

Please take some time to read the FAQ. There, you’ll learn how to best share command/ data/ output.

I’m afraid to say that your post, at least to me, is barely readable.

That said, hazarding a guess, maybe the issue is related to the bounds, when you selected - rprov - without informing it is a categorical variable.

[Valerie Herz]

Dear Marcos,
many thanks for your message. So sorry I did not use the command in my previous post so that it is readable for everyone.
That could be it, that I did not inform state that it is a categorical variable. How would I do that?
Hopefully my do- file is better readable now!

// run the regression model
xtgls builtlastyear rprov existingboats c.c_rprov##c.c_existingboats standalone GDPgrowth2 leisure olympic texist i.year, panel(hetero)

// get plausible/interesting values to plot
summarize rprov existingboats
margins, dydx(rprov) at(existingboats=(30(5)75)) vsquish

// get the adjusted predictions
margins, at(rprov=(1 2) existingboats=(30(5)70)) vsquish

// plot the predictions
marginsplot, noci x(rprov) recast(line) xlabel(30(5)75)

Output:
Delta-method dy/dx Std. Err. z P>z [95% Conf. Interval]

rprov _at
1 . (not estimable)
2 . (not estimable)
3 . (not estimable)
4 . (not estimable)
5 . (not estimable)
6 . (not estimable)
7 . (not estimable)
8 . (not estimable)
9 . (not estimable)
10 . (not estimable)

Again, any help is highly appreciated!

[Daniel Devine]

Hard to tell exactly what your variables are, but put it into the model as i.rprov instead of rprov and see what happens!

[Valerie Herz]

Thanks will try that. "builtlastyear" is my dependent variable, rprov is an independent variable and existingboats is the moderator.

[Marcos Almeida]

Valerie, as you may have realized, you could help us better to help you. Let me also remark that reading carefully the FAQ is a great starting point.

This being said, I will to make a few suggestions.

Since you didn't share data we could work on, I had to prepare an example by myself:

. webuse invest2

. gen highstock = stock > 311 & !missing(stock)

.  xtset company time
       panel variable:  company (strongly balanced)
        time variable:  time, 1 to 20
                delta:  1 unit

.  xtgls invest c.market##i.highstock, panels(hetero)

Cross-sectional time-series FGLS regression

Coefficients:  generalized least squares
Panels:        heteroskedastic
Correlation:   no autocorrelation

Estimated covariances      =         5          Number of obs     =        100
Estimated autocorrelations =         0          Number of groups  =          5
Estimated coefficients     =         4          Time periods      =         20
                                                Wald chi2(3)      =     441.11
                                                Prob > chi2       =     0.0000

------------------------------------------------------------------------------------
            invest |      Coef.   Std. Err.      z    P>|z|     [95% Conf. Interval]
-------------------+----------------------------------------------------------------
            market |   .1044449   .0100809    10.36   0.000     .0846867    .1242031
       1.highstock |  -52.95075   41.15659    -1.29   0.198    -133.6162    27.71469
                   |
highstock#c.market |
                1  |   .0903252    .017791     5.08   0.000     .0554555     .125195
                   |
             _cons |  -17.29815   10.23841    -1.69   0.091    -37.36506    2.768759
------------------------------------------------------------------------------------

. margins highstock, at(market=(200 (200) 6200)) vsquish

Adjusted predictions                            Number of obs     =        100

Expression   : Fitted values, predict()
1._at        : market          =         200
2._at        : market          =         400
3._at        : market          =         600
4._at        : market          =         800
5._at        : market          =        1000
6._at        : market          =        1200
7._at        : market          =        1400
8._at        : market          =        1600
9._at        : market          =        1800
10._at       : market          =        2000
11._at       : market          =        2200
12._at       : market          =        2400
13._at       : market          =        2600
14._at       : market          =        2800
15._at       : market          =        3000
16._at       : market          =        3200
17._at       : market          =        3400
18._at       : market          =        3600
19._at       : market          =        3800
20._at       : market          =        4000
21._at       : market          =        4200
22._at       : market          =        4400
23._at       : market          =        4600
24._at       : market          =        4800
25._at       : market          =        5000
26._at       : market          =        5200
27._at       : market          =        5400
28._at       : market          =        5600
29._at       : market          =        5800
30._at       : market          =        6000
31._at       : market          =        6200

-------------------------------------------------------------------------------
              |            Delta-method
              |     Margin   Std. Err.      z    P>|z|     [95% Conf. Interval]
--------------+----------------------------------------------------------------
_at#highstock |
         1 0  |   3.590824   8.748105     0.41   0.681    -13.55515    20.73679
         1 1  |  -31.29488   37.49927    -0.83   0.404    -104.7921    42.20235
         2 0  |    24.4798   7.507573     3.26   0.001     9.765226    39.19437
         2 1  |   7.659147   35.22134     0.22   0.828    -61.37341    76.69171
         3 0  |   45.36878   6.657924     6.81   0.000     32.31948    58.41807
         3 1  |   46.61317   33.04666     1.41   0.158     -18.1571    111.3834
         4 0  |   66.25775   6.357847    10.42   0.000      53.7966     78.7189
         4 1  |   85.56719   30.99697     2.76   0.006     24.81424    146.3201
         5 0  |   87.14673   6.681801    13.04   0.000     74.05064    100.2428
         5 1  |   124.5212   29.09871     4.28   0.000      67.4888    181.5536
         6 0  |   108.0357    7.54988    14.31   0.000     93.23821    122.8332
         6 1  |   163.4752   27.38336     5.97   0.000     109.8048    217.1456
         7 0  |   128.9247    8.80255    14.65   0.000      111.672    146.1774
         7 1  |   202.4293   25.88734     7.82   0.000      151.691    253.1675
         8 0  |   149.8137   10.30044    14.54   0.000     129.6252    170.0021
         8 1  |   241.3833   24.65059     9.79   0.000      193.069    289.6975
         9 0  |   170.7026    11.9517    14.28   0.000     147.2777    194.1275
         9 1  |   280.3373   23.71372    11.82   0.000     233.8593    326.8153
        10 0  |   191.5916     13.701    13.98   0.000     164.7381    218.4451
        10 1  |   319.2913   23.11322    13.81   0.000     273.9902    364.5924
        11 0  |   212.4806    15.5152    13.69   0.000     182.0713    242.8898
        11 1  |   358.2453    22.8756    15.66   0.000       313.41    403.0807
        12 0  |   233.3696   17.37399    13.43   0.000     199.3172     267.422
        12 1  |   397.1994   23.01211    17.26   0.000     352.0965    442.3023
        13 0  |   254.2585   19.26446    13.20   0.000     216.5009    292.0162
        13 1  |   436.1534   23.51622    18.55   0.000     390.0625    482.2443
        14 0  |   275.1475   21.17814    12.99   0.000     233.6391    316.6559
        14 1  |   475.1074   24.36513    19.50   0.000     427.3526    522.8622
        15 0  |   296.0365   23.10925    12.81   0.000     250.7432    341.3298
        15 1  |   514.0614   25.52447    20.14   0.000     464.0344    564.0885
        16 0  |   316.9255   25.05377    12.65   0.000      267.821      366.03
        16 1  |   553.0155    26.9542    20.52   0.000     500.1862    605.8447
        17 0  |   337.8144    27.0088    12.51   0.000     284.8782    390.7507
        17 1  |   591.9695   28.61383    20.69   0.000     535.8874    648.0516
        18 0  |   358.7034   28.97222    12.38   0.000     301.9189    415.4879
        18 1  |   630.9235    30.4658    20.71   0.000     571.2116    690.6354
        19 0  |   379.5924   30.94242    12.27   0.000     318.9464    440.2384
        19 1  |   669.8775   32.47723    20.63   0.000     606.2233    733.5317
        20 0  |   400.4814   32.91819    12.17   0.000     335.9629    464.9998
        20 1  |   708.8316   34.62034    20.47   0.000     640.9769    776.6862
        21 0  |   421.3703   34.89858    12.07   0.000     352.9704    489.7703
        21 1  |   747.7856   36.87216    20.28   0.000     675.5175    820.0537
        22 0  |   442.2593   36.88285    11.99   0.000     369.9702    514.5484
        22 1  |   786.7396   39.21399    20.06   0.000     709.8816    863.5976
        23 0  |   463.1483   38.87041    11.92   0.000     386.9637    539.3329
        23 1  |   825.6936   41.63063    19.83   0.000     744.0991    907.2881
        24 0  |   484.0373   40.86077    11.85   0.000     403.9516    564.1229
        24 1  |   864.6476   44.10978    19.60   0.000     778.1941    951.1012
        25 0  |   504.9262   42.85354    11.78   0.000     420.9348    588.9176
        25 1  |   903.6017   46.64149    19.37   0.000      812.186    995.0173
        26 0  |   525.8152   44.84841    11.72   0.000     437.9139    613.7165
        26 1  |   942.5557   49.21763    19.15   0.000     846.0909     1039.02
        27 0  |   546.7042    46.8451    11.67   0.000     454.8895    638.5189
        27 1  |   981.5097   51.83159    18.94   0.000     879.9217    1083.098
        28 0  |   567.5932    48.8434    11.62   0.000     471.8619    663.3245
        28 1  |   1020.464   54.47793    18.73   0.000      913.689    1127.239
        29 0  |   588.4821    50.8431    11.57   0.000     488.8315    688.1328
        29 1  |   1059.418   57.15213    18.54   0.000     947.4016    1171.434
        30 0  |   609.3711   52.84406    11.53   0.000     505.7987    712.9436
        30 1  |   1098.372   59.85048    18.35   0.000      981.067    1215.677
        31 0  |   630.2601   54.84613    11.49   0.000     522.7636    737.7565
        31 1  |   1137.326   62.56984    18.18   0.000     1014.691     1259.96
-------------------------------------------------------------------------------

. marginsplot

[Valerie Herz]

I finally managed to get results. THANK YOU!! so much!!

[Marcos Almeida]

Thank you for informing your query reached a satisfactory closure.