I agree that there is too much information here to stay anonymous from your boss.
Instead, you could generate the histogram of the entire sample set, perhaps curve fit, so it's not obvious for small sample sizes, how many people contributed. Then you put a little red "You are here" dot on the histogram so they see how they compare. This robs the employer of any data they can use to see who partook in the experiment, while still giving the same information back to the employee.
Instead, you could generate the histogram of the entire sample set, perhaps curve fit, so it's not obvious for small sample sizes, how many people contributed. Then you put a little red "You are here" dot on the histogram so they see how they compare. This robs the employer of any data they can use to see who partook in the experiment, while still giving the same information back to the employee.