What do you think about getting all of the three degrees from the same college? especially if you want to have a career in academia?
Depends on the college.
You definitely won’t be getting a job at that same college. It’s typically frowned upon to do that.
^I think “definitely” is a strong word, and it depends on the field and the university. A couple of months ago someone asked a related question about EE/CS, and I happened to peek at the educational histories of professors in the EE/CS department at MIT. An astonishing number of them had also gotten their PhDs at MIT, and many of them got master’s and bachelor’s degrees there as well. At my current university there are also several professors who got their master’s and PhD (and also postdoc!) here and are still working here as research faculty. My alma mater PhD department also frequently hired their own graduates, although it was less common that those graduates got BAs at Columbia.
The general theory I have (supported by backgrounds of some professors I know) is that the strength and quality of your department matters, as well as the fit. For example, Stanford is one of the top undergrad institutions in the country AND one of the top 5 programs in my field. If a psychology student went to Stanford for her BA and then stayed there for her MA/PhD, particularly if she was doing certain types of research (like stereotyping and prejudice, which are big there), nobody would look down on her when she went on the job market: Stanford is an excellent place! Another example of that is Michigan; actually, it’s pretty common in the Michigan psych department for people to get their MAs and PhDs there, sometimes also their BAs, and stay (or leave for a postdoc or a few years on the tenure-track and come back). At the top programs in the field, no one is going to question why you stayed - it’s self-evident.
Also, top programs tend to hire a lot of their own.
The same is more or less true for fit. Let’s say that you went to UCSB (a top 30-40 program in my field, and still excellent), and you started working with a specific professor I’m thinking of - who is a huge name in the field - doing stigma research, and decided to stay on for your PhD to continue that work. If your work fit in/complemented that professor’s work very nicely, again, no one would question why you decided to stay there.
Where getting all three degrees from the same university begins to hurt you is if it’s not clear why you stayed there, or rather, if it doesn’t seem like there was a GOOD reason for you to do so. If your undergrad psych department is mid-ranked in the field, people will wonder whether you just stayed because it was comfortable. Or, if you stay in your BA department but it’s clear that your research isn’t really a good fit with what they’re doing there, people will wonder why the heck you decided to stay when you could’ve left and worked with someone else.
The disadvantage that staying at one place puts you at is that your network is smaller than it would otherwise be. I got my BA and my PhD at two different places, and my postdoc is at a third place, so I have networks at two large research universities and my mentors from my small LACs - all of whom remember me and think about me and pass on information and job ads when they come across their desk, and who I can draw upon for recommendations or advice. You also learn different perspectives - fields are practiced differently in different departments, and it’s good to have a diversity of experiences to form your own philosophies and approaches in your science. The thing that you can do to mitigate the questions/concerns is build a wide network. If you stay in your BA department, your mentor can help you do that - network with people at other departments, collaborate across universities, go to lots of conferences, participate in enrichment programs, do a year-long exchange with another university, do a dissertation fellowship at a different university…there are lots of options for building networks across institutions even if you stay in the same department.
So the tl;dr version is
-It’s not a bad idea if your department is a top-ranked one or if you are a good fit with a faculty member there.
-It’s a bad idea if your department is not well-ranked and/or if you don’t have a good fit with a faculty member at that department.
-Also, check your field and the norms within it. A good way to do that is look at the top 5-10 programs in the field and see how much intradepartmental breeding there is (e.g., the number of faculty who have just stayed there forever). My bet is that this goes down as the ranking of the department goes down.
-Lastly, ask yourself what kind of department you want to be teaching and doing research in. The prestige and reputation of your department, and the size of your network, is far more important if you want to be a well-respected researcher at an R1 university winning grants left and right. It’s (somewhat) less important if you would love to teach at a regional comprehensive university or a small non-elite teaching college. (The elite LACs care just as much about prestige as the R1s, though.)