So, now that graduate school is just around the corner, I'm left with the daunting task of picking a school and research group that I'd like to work with. This question may sound silly, but all other things being equal, but what age would people recommend a research advisor be? The more I think about it, the more important it seems to be. On the one hand, I could join a newly-formed research group where the professor is 8 or 9 years older than me, someone who is about as old as a sibling. On the other extreme, I could work with an endowed chair who's older than my grandfather. It seems to me that there are advantages and disadvantages with the different age groups. Does anyone have any suggestions, ideas, or experiences?