Is it okay for me to show some other publication's data for data comparison reasons without prior permission if I properly reference/cite their work? Suppose publication Smith (2016) had a study that investigated whether professors liked apples, and found that they did.

Now suppose that I wish to have my own study that investigated whether students also liked apples, and to what degree would this be compared to professors.

Would it be necessary for me to ask Smith for permission to show their numbers when I am making the statistical comparison between my data and Smith (2016) data?

If I reference Smith (2016) when presenting my work, do not claim the data on professors to be my own, and use the same inventory of questions (which Smith (2016) themselves used from another source), I would assume that this would not be considered plagiarism and I would not have to receive permission, but I wasn't entirely sure.

In other words, is it okay for me to show some other publication's data for data comparison reasons without prior permission if I properly reference/cite their work?

*This project, as it stands, only has intentions for conference presentations and not publication if that changes anything.
Utilization of data sets (acquired from other academic resources) is fairly common; specially when you need to compare your analytical method with the other one's in view of performance, precision, etc. In such case, people often try to use a pre-assessed data set of their own or some other study. All you need to do is referencing the used data set, carefully.

Answer to question #11, here, says:


  Data cannot be copyrighted, so you are free to use data to create any figure you like *[or any analysis you need]*. The source of the data must be properly acknowledged