I applied through college or university. The process took 2 months. I interviewed at Ipsos
Interview
3 rounds of interview - Group interview, case, and case interview. These were mainly with the team manager
After the 3 rounds of interview, I met with the department head for a get to know you session
Simple and easy, mainly focuses on regression, basic stats, and basics of coding language like python and sql. Not very technical in nature. Good to just learn multiple linear regression and excel skills just in case.
Multiple rounds of behavioral interviews and one case interview with members of the team. The interviews do not require prep in advance but it is good to know case study frameworks
I applied online. I interviewed at Ipsos (Londres, Inglaterra)
Interview
It was Straightforward and consisted of 2 stages. First stage was an introductory telephone interview and 2nd was an in person interview with an activity that I had completed beforehand.