st: economic interpretation mfx!!

["Augusto Pallavicini" <agupalla@hotmail.com>]

Hi all, I need help with the interpretation of the output of the marginal 
effects after tobit... I know this is conditional...

here is what I think...

One more level of education increases the expected amount willing to pay by 
61.2% and one more level of income by 29.2%, ceteris paribus. Then, having a 
positive opinion about wind energy (dummy opinion2) raises the expected 
amount willing to pay by 208.7% whereas being concern about the environment 
(dummy statement2) does it by 148.2%, ceteris paribus

Are these conclusions correct? Do I need to do something else with the 
dummies to find out the mg effect (because I think it's wrong)?

Thanks in advance

Below is the output

mfx compute, predict(e(0,.))

Marginal effects after tobit
     y  = E(pay|pay>0) (predict, e(0,.))
        =   4.332974
------------------------------------------------------------------------------
variable |          dy/dx         Std. Err.     z       P>|z|        [ 
95% C.I.   ]      X
---------+--------------------------------------------------------------------
educat~n |     .612348      .33726    1.82   0.069  -.048671  1.27337 
2.84058
 income |      .2918185      .17118    1.70   0.088  -.043688  .627325 
3.50725
 gender*|    -.1665404      .63723   -0.26   0.794   -1.4155  1.08242 
.521739
    age |       -.0552524      .40434   -0.14   0.891  -.847737  .737232 
3.52174
coastal*|     -.8215083      .63314   -1.30   0.194  -2.06245  .419432 
.623188
   bill |          .0053813      .01494    0.36   0.719  -.023894  .034657 
55.0435
children*|     .5257885      .83808    0.63   0.530  -1.11681  2.16839 
.623188
opinio~2*|   2.087348       .6481    3.22   0.001   .817098   3.3576 
.869565
statem~2*|   1.481657      .62187    2.38   0.017   .262813   2.7005 
.797101
------------------------------------------------------------------------------
(*) dy/dx is for discrete change of dummy variable from 0 to 1




AP 

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