Use of embedded quotation marks within locals in Stata

Proper use of single and double quotation marks is essential when working in Stata, especially when writing loops where locals can be a huge time and memory saver. The use of single and double quotation marks is rather straightforward (using ` and ‘ for single, and ” for double quotation marks). You can rather easily define a local, e.g. based on the average of a variable

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Using Stata to randomise vignettes in NetQuestionnaire

One huge disadvantage of NetQuestionnaire (NetQ) is that randomisation is only possible for the order of sub-items of questions. There is, however, a way to use Stata to make anything random (e.g. the order of questions, content of questions). Below, I describe a way how to generate randomly sets of vignettes. At the end of the do-file, text is saved to an Excel-file). Merged with an address-list, this information can be imported to NetQ, and used in questions using the NetQ-variables. Continue reading

Why doesn’t this do-file run through …?

Quite often a do-file is written to run on various data-files that all seem to be the same. Say, you have done it for one year of a data-set and want to repeat the same for the subsequent years that you have data. Now, a check whether the data actually has some data (given your selection) is often a good idea, here is how I did it in a recent project:

assert `r(N)'>1

I am using the saved return local variable r(N) that STATA automatically generates after count. This is a need feature that you should consider for many other commands (try return list after your favourite command).

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