The annual data science skills and salary survey from O’Reilly is now freely available from their website. The survey uses responses from 800 participants from over 50 countries.

Inside are comparisons of the different tools used by data science practitioners and the corresponding salary they can expect to earn. The data is also cut by geographic location, career level, academic record, and industry type amongst others.

A lot of the key findings are expected: R, Python, and SQL are the most widely used tools; top USA salaries are in California. But some results are more surprising: Spark has emerged as a popular tool in 2014; the ‘Entertainment’ industry boasts the highest median salary for data scientists.

Highlights in this edition include a cluster analysis of the tools used, which showed the emergence of a new cluster around Max OS X, MySQL, and D3. There is also salary regression model which puts a dollar weight on geographic, demographic, and company predictors to give an in-sample R2 of over 50%.

A shame the number of respondents is so low but all in all a good read to give a directional sense of the state of play in 2014 and what might be up and coming in 2015.