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In simple language, a hypothesis is an educated guess of where the bottleneck might be.

Hypotheses exist because they save time.

It is usually not economically feasible to run thorough investigations for every single aspect of business. Consultants usually “guess”… or should I say… hypothesize where they can find the insights and drill down there.

There are 4 secret rules of thumb that I will be giving you. These are very easy-to-apply tips which many candidates miss.

  • No.1: Hypotheses need to follow the frameworks chosen
  • No.2: Hypotheses should be top down
  • No.3: Always have a hypothesis. It does not have to be right all the time.
  • No.4: Hypotheses should be based on the information provided.

Most of the insights above are applicable for candidate-driven and mixed cases. For pure interviewer-led cases, the game is a little bit different. Since you do not set up the approach and direct the flow, hypotheses are needed mostly when the interviewer explicitly asks a “hypothesis” questions.

Some common forms of “hypothesis questions” are:

  • Why do you think that happens?
  • What are some hypotheses you can think of that explain abc?
  • What are some possible reasons for xyz?

For these questions, my list of tips for you is a little bit different.

  • No.1: You need more than one hypothesis. Now the job is to list them out, not to use them.
  • No.2: Your proposed hypotheses should be structured and MECE. Please refer to our video on the concept of MECE for more details.
  • No.3: This is a modified version of No.3 we mentioned above. Hypotheses in interviewer-led cases do not necessarily need to be true. As long as they can explain the facts, then it’s considered good.
  • No.4: This is exactly the same as the candidate-led version. Hypotheses should reflect the data you have! This is the universal rule of thumb for any hypothesis.

So exactly how many of the difficult concepts left will you have to learn to ace a Case Interview?

Check out our exclusive Case Interview End-to-End Secrets Program for everything you need to impress your Interviewer! 

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  • Thao Lee

    Thanks for your insightful article!
    I sometimes feel difficult to distinguish between hypothesis and fact-based conclusion. Hope you will explain this difference more in your next video.

  • Lynn Phan

    I enjoyed this video, the instructions as well as other posts from your website, very clear and not too difficult to follow.

  • Kelley

    I actually feel more confident when you say there’s nothing wrong with a wrong hypothesis, I was always nervous about that

  • Amy

    great video and instruction, just think that the way you present your rule of thumb are not very MECE 😛 (btw thanks for the MECE video too!)

  • Amy

    Great video! Just think that the way you present the rule of thumb is not very MECE 😛 (btw thanks for the MECE video too!)