I'm a CS undergrad from an average state school applying to statistics programs this fall. Earlier my interests were more focused on AI/NLP/speech, so I volunteered at a EE professor's speech processing lab for several semesters; it was mostly mundane work like data collection (including designing a web interface for users to listen to/evaluate speech samples etc.), nothing really considered "research" in the field. Recently I've been self-studying some real analysis/stochastic processes/Bayesian statistics and reading more theoretical work, and decided statistics PhD is probably a better fit for me.
Does it still make sense to have a LOR from my EE professor? BTW he is senior and established in the speech processing field; due to how busy he is I've interacted more with his grad students. I asked him in person and he said he's happy to write me a letter.
I'm also taking Real Analysis 1 this semester, and I've been wondering if I should visit my analysis professor's office hours more and get a LOR from him instead. He's a young tenure-track assistant prof doing work in dynamical systems. (I've self studied through measure theory so Analysis 1 will be an easy A for me; I'm taking it b/c it seems many statistics PhD programs require analysis on transcripts) The problem here is of course he may not know me for very long by November/December.