The first place I would look is size of dataset and correlation effects from multiple self-reporters working for the same company. Big companies tend to pay mo

The first place I would look is size of dataset and correlation effects from multiple self-reporters working for the same company. Big companies tend to pay more in the software industry. Big companies also tend to have standardized on tabs or spaces internally to simplify the problem of merging code across developer teams. So if you find out that, hypothetically, Amazon, Microsoft, Google, and Facebook have all standardized internally on spaces, that alone could account for the data.