How to check the data is generated by machine or human? I have a bunch of data points (about 300 samples in total), each sample is a number from 1 to 3 (from {1, 2, 3}).
These numbers are supposed to come from a survey. Are there any statistical methods to determine whether these sample are generated by human graders, or are they machine generated?

If you have labelled instances (i.e. you know if a sample is generated by machine or by human) you can train a machine learning classifier to find the pattern which separates the two classes.
Not sure if you would count a ML method as "statistical method".
