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Anonymous A
on Apr 15, 2020
Global
I want to receive updates regarding this question via email.

How to validate the final number in market sizing question

Wondering once a market size is estimated in a stand alone market sizing question, what are the typical ways to validate the final number? ie. you can compare a country's market size to global market size. What if you don't have any benchmark number you can compare to on top of your head? Appreciate your thoughts here.

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Coach
on Apr 15, 2020
150+ interviews | 6+ years experience | Bain, Kearney & Accenture | Exited startup| London Business School

Hi there,

In addition to what is already mentioned (sense checking and comparing to another industry) it would be good to reflect on the assumptions made / variables use. Specifically, look at how sensitive some of these might be. In other words, if you were to do the same sizing but you would assume a sales price of e.g. $90 vs $100, how would it affect the outcome? 

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Emily
Coach
on Apr 15, 2020
9 years in MBB Southeast Asia & China| 8 years as MBB interviewer | Free intro call

Hi there,

Other than global market size, depending on the exact question, you can try to compare in other ways that come a bit closer to your life. E.g.

- Compare to another industry you roughly know in the country, and see intuitively whether it makes sense (should the estimated market be bigger or smaller than this benchmark industry?)

- If the estimate is for B2C business, compare that number to the population and check the per capita number, does it make sense?

Try to see if you can use some of the common sense understanding in life to sense check. Even if you couldn't find a good benchmark, don't worry too much. You are tested more for whether you can think logically in a systematic approach. If you get that accomplished, but just make a wrong assumption because you are not familiar with certain industry, you would still get the most credit.

Best,

Emily

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Clara
Coach
on Apr 15, 2020
McKinsey | Awarded professor at Master in Management @ IE | MBA at MIT |+180 students coached | Integrated FIT Guide aut

Hello!

This validations are very very common, specially as you come to the end of a case.

Usually you can leverage the following -take for instance that you were calculating a cost and you want to stress-test the number):

  • Benchmark with historical client´s data: looking at changes from the past is always going to give you hints
  • Benchmark against competitors in the cost´s breakdown
  •  

Hope it helps!

Cheers,

Clara

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Deleted user
on Apr 30, 2020

Hey,

look through your assumptions and try to make a comparison with a similar industry.

Develop your business judgement, whether it all makes sense.

Hope it helps,

André

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Antonello
Coach
on Apr 30, 2020
McKinsey | NASA | top 10 FT MBA professor for consulting interviews | 6+ years of coaching

Hi, 
it depends on the question and on the remaining time for the case. Usually, common sense is enough, otherwise, you can try to quickly set up a different approach to the case (e.g. bottom up if you did a top down)

Best,

Antonello

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Luca
Coach
on Apr 30, 2020
BCG |NASA | SDA Bocconi & Cattolica partner | GMAT expert 780/800 score | 200+ students coached

Hello,

THere are different ways that are strictly correlated with the specific case. FOr example, once that you have calculate the volume of american sneakers market, you could divide your number by the American population to get the "Expenditure per capita" KPI.

Feel free to text me a specific example if you want to discuss it.

Best,
Luca

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