What is more important for the admission of masters program? For the admission in Masters Program, what is more important, ranking/reputation* of the University or the strength of the research group in the field (say, Machine Learning) you wish to apply ?

I have been told that the advisor and the research group is the most important criteria for PhD admission . So, I researched about research groups in various Universities. I found out that, sometimes a less prestigious university had a great research group in a particular field and a few times reputed university had a weak research group.  So, I am confused whether the prestige of a university matter more than a strong research group in


Industry (Job after masters )
Research (Apply for a PhD after the masters


For example, UT Austin has a strong reputation in computer science. However, it seems to me that their machine learning groupis small.  So, in situations like this what should a master's applicant do ? Go for UT Austin because of its reputation or decline the offer because of lack of strong research group in ML. 

*The ranking/reputation here is the US news Grad Schools ranking in the field of computer science.
For a purely course-based Masters, in which you do not do research, the research strength of the university obviously won't matter very much.

For a Masters in which you do research and create a thesis, however, the strength of the research group is likely to significantly outweigh the reputation of the school.  This is because the most valuable thing that you can have when applying either for a Ph.D. or an industrial job is a strong recommendation letter from a respected colleague.

If all I know about a student is that they got a Masters from MIT or Berkeley, well, a lot of students get such degrees, and some are excellent while others are worthless outside of the structured environment of the classroom.  On the other hand, if the student comes from Mid-Ranked U with a strong personal recommendation from somebody whose work I know and respect, then they are likely a much better prospect than the unknown from a high-ranked university.