Do you need to ask the interviewer if each of your assumptions sound reasonable and wait for a yes before you use them? For eg if you assume 80% of the population can afford this product and give a reason why, then you ask if they are ok with this assumption and only proceed if you get a green signal? Or should you do the full market sizing just stating your assumptions and rationale without waiting for a green signal on whether they are reasonable?
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Top answer
Ian
on Aug 16, 2021
Coach
Ex-BCG | NYU Stern | MBB, Tech, & Strategy Coach | 5,000+ Sessions | 500+ Offers | 1,000+ Candidates | 100+ Countries
Hi there,
You should not do this.
One of the main points of market sizing is to assess whether you can approach the problem and make reasonable assumptions on your own.
The interviewer will not help you here and it's up to you to make reasonable assumptions, assess them, and drive the market sizing forward based on what you know about the world!
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Deleted user
on Aug 20, 2021
Hello,
Don't ask the interviewers or wait for a green light - proceed with the full market sizing stating your assumptions and rationale. If needed, the interviewer will stop and correct you, but usually they won't because they care more about your thought process and rationale than the actual numbers you come up with.
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