Problem when generating synthetic data

[brandmaier]

Creating synthetic data from Allison Horst's penguin data fails (https://raw.githubusercontent.com/bvreede/worcshop/master/data/penguins.csv) The error is caused because there is one column of strings. I assume this could be fixed by turning this column into a factor. However, there is a good chance that people will have strings in their data files, e.g., a comment column. Should we, by default, drop all string columns (while issuing a warning) before generating synthetic data?

[cjvanlissa]

I believe we should not - the modeling is done entirely by external functions; ranger() by default.

Perhaps we can do something to explain the process of the synthesizing better to people, so that they understand that it might break on the data type?

[brandmaier]

Alright, then let's not treat this as a bug. I like the approach that we outsource this responsibility. Still, how do we best help people to proceed from this point on? I think it's difficult for beginners to figure out how to fix the problem of "synthetic data could not be generated".

[cjvanlissa]

It's VERY difficult. We're also limited by resources, of course. I know that Marvin Wright would be open for a pull request that makes ranger suitable for a wider range of input/outcome variables, so we could try to make ranger itself more flexible. Another solution would be to wrap ranger with a function that preprocesses variable types using some sensible defaults.

[cjvanlissa]

In the meanwhile, I removed the error wrapping from the call to synthetic(). This means that if data synthesis fails - the entire function fails, so users are more aware of the problem.