Using loops to run (and export) many regressions / Usando loops para correr (y exportar) múltiples regresiones
español The use of loops becomes essential when needing to perform repetitive calculations. Looping has many advantages, for example, when needing to do corrections in all the calculations specifications. So here are some interesting features that you would like to do when implementing a loop to run many regressions, and export their outputs: Choose the appropriate method for the regression according to the type of dependent variable. For instance, you might want to estimate the model using OLS (regress) when the dependent variable is continuous and or a probit or a logit model when it is discrete (a dummy variable). Progressively add explanatory variables to the model and export all the output in a single table. This can be done using outreg2 ‘s replace and append options, but if you want instead to write a single command line inside a loop you will have to make the appropriate changes. So assume that you want to estimate a number of econometric models that are quite similar in terms of the explanatory variables that are incorporated, but differ between them in terms of the dependent variables, for example : Model 1: outcome1=b1*x1+b2*x2+b3*X3+b4*X4+e Model 2: outcome2=b1*x1+b2*x2+b3*X3+b4*X4+e In addition you also want to progressively add sets of explanatory variables. So for instance you…
Importing text files into Excel Part II / Importar archivos de texto al Excel Parte II
español For those who find useful to transfer the output of their statistics and regressions to Excel, here is another macro that might be useful. As in the last case, imagine that you are dealing with many tables of statistics and regressions that you have computed with Stata, and you will find useful to take them all to Excel. Such a thing might be useful for visualization, comparing statistics (robustness checks), formatting the tables for presentations or publications, elaborating further graphics, and so on. Building on the macro presented in the previous post, this time I built another one to deal with importing multiple files simultaneously. To see how it works, imagine, as an example, that you have 5 key variables that you are analysing and for each of them you have produced 4 tables (corresponding, for example to different estimation methods) and exported each respectively to a text file. That gives a total of 20 tables to be imported from Excel. First, it might be useful to organize the text files information in a table in Excel as shown in the table below: Using the information in the previous table, the multipletextload macro will : i. Generate a new…