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McKinsey PST Speed Training – How to read faster

By Don Truong May 30, 2017UncategorizedNo Comments

McKinsey PST Speed Training – How to read faster

By Don Truong | Uncategorized | No Comments


This program is developed based on a research by Princeton University as a general guide to increase reading speed of any kind. Of many speed reading programs we have tested, this is the most structured and effective, even in the consulting and Problem Solving Test context. The result is just amazingly positive. You can expect to at least double your reading speed after just a few hours of intense practice.

We adopt this program and tailor it to further suit your purpose of training for the McKinsey PST.

Refer to the video for an overview of our rigorous study plan. This document is an important piece of the SPEED part of that overall study plan.

Check out at the end of this post to download the full pdf version of McKinsey PST Speed Training – Fast Reading guide!

Why is it possible to vastly increase reading speed?

The simple reason is that your brain can comprehend at much faster speed, something at least 2 to 3 times your normal reading speed. The only bottle neck holding your back is just your eyes.

Don’t believe it?

Just go into this video (or any other one) and double the playing speed (Youtube lets you do that). You can still comprehend just fine. In fact, you can even triple it, but at that speed, your ears (not your brain) can’t keep up.

By default, your ears can sustain a higher speed than your eyes, but the eyes have higher ceiling.

The point I am making here is that, by training just your eyes, you can vastly increase your reading speed, just because your brain has much more unused power.

Three loopholes limiting the performance of your eyes

Problem A) Your eyes read by making a series of “photo shoots”, instead of a smooth continuous “video”

Each of those “photo snapshot” has the size of about 2 – 3 cm, so get over a typical text line, you would need about 5 – 10 shots depending on text size and reading distance. This tendency is not efficient and slows you down a lot.

To demonstrate this, close one eye, put a finger on it, and try to read a normal text. You can literally feel the “shot” motion your eye makes, just like a camera.

Problem B) You subconsciously engages in back-skipping and regression

Your eyes don’t progress in one direction moving forward all the time. Once in a while it goes back and “double check” on whether you misread anything. This whole process happens at automatically without you noticing it. It’s on the subconscious level. This costs you about 20 – 30% of the reading time. And generally this tendency is unnecessary.

Problem C) Each “snapshot” your eyes make is not in “landscape” setting, but rather in a square one.

Your eyes have great horizontal peripheral vision span, almost up to 180-degree (to test this, looking straight forward, then put both your hands on about the same horizontal surface with your eyes, and slowly moving them horizontally away from your view … you can still see your hands when it is almost behind you). Ironically, you only use 2 – 3 cm of that vision span while you read.

Now comes the training content

You will (1) learn technique, (2) learn to apply techniques with speed through conditioning, (3) then learn to test yourself with reading for comprehension.

These are separate, and your adaptation to the sequencing depends on keeping them separate. Do NOT worry about comprehension. Or in other words, don’t worry about your brain. For sure it is capable of comprehending everything your eyes throw at it. At beginning steps of the training program, just pressure your eyes into the habit which allow it to read fast. In that process, you will lose the attention to the content of the text itself. That’s why it may seem like you lost comprehension with speed reading. But be certain that comprehension will come back easily, once your eyes developed the habit.

The adaptive sequence is: technique -> technique with speed -> comprehensive reading

As a general rule, you will need to practice technique at a way higher speed of your ultimate target reading speed. For example, if you currently read at 300 wpm (words per minute) and your target reading speed is 900 wpm, you will need to practice technique at 1,800 words-per-minute, or 6 pages per minute (10 seconds per page).

We will cover two main techniques:

Technique 1: Trackers and Pacers (to address A and B above)

Technique 2: Perceptual Expansion (to address C)

Step 1: Determining your current Speed

You would want to know your progress after this training. So please, determine your current reading speed, try this 100-word McKinsey-style paragraph, take out a watch, and time yourselves (in exact seconds). Please do not read faster than normal. Make sure you read with comprehension.


Set …

Go …

Paragraph #1:

A smart home will be akin to a human central nervous system. A central platform, or “brain,” will be at the core of such smart home. Individual homebots of different computing power will radiate out from this platform and perform a wide variety of tasks, including supervising other bots. Homebots can be as diverse as their roles: big, small, invisible (such as the software that runs systems or products), shared, and personal. Some homebots will be companions or assistants, others wealth planners and accountants. We will have homebots as coaches, window washers, and household managers, etc., all throughout our home.

Now to make the measurement more accurate, try another paragraph, everything else stays the same.Note down your time (in seconds).

Turn to the next page when you are ready

Paragraph #2:

That level of home improvement presents significant opportunities, threats, and changes for appliances and devices that have been part of our home life for generations. The new home will be built on a foundation of platforms and ecosystems, whose producers will need to establish new levels of trust with their customers. Competition will take place not just for the consumers who inhabit the smart home, but for the interactions between consumers and homebots that increasingly will shape buying behavior. It’s not too early for a wide range of players to start laying the groundwork for success in this futuristic home…

Now to be really sure, try another one on the next page.Note down your time (in seconds) this time.

We are ready when you are …

Paragraph #3:

Platforms will provide the foundation to integrate different devices while providing a consistent interface for the consumer. Frontrunners include Amazon, Apple, Google, and Samsung; start-ups at various points in the development cycle will be part of the mix, as well. The winners will deliver omnipresence through ubiquitous connectivity and go-anywhere hardware, as well as integration, with bots collaborating among each other and linking to third parties’ products and services. If the recent past is any indication, it’s likely that multiple platform standards will evolve. That will present complexities both for consumers and businesses but will foster new, niche opportunities, as well.

Ok, three takes. This gotta be a fair measurement. Now please calculate the number of the three trials. Then take 6,000 divided by that number (in seconds), you have your wpm. How was your performance? 

Step 2: Learn and apply the Technique #1 – Trackers & Pacers

The end goal of this Technique #1 (Trackers & Pacers) is to fix Problem A and B. The tracker and pacer you use will help you transition from a somewhat unorganized series of “photo shoots” to a nice and smooth video-like motion.

So, try that paragraph #1 again, but this time with a much faster speed. Try to finish the paragraph under 6 seconds. That makes one line less than 1 second. The ideal speed for this drill is 0.5 second per line.

Again like I said above, we are trying to push your eyes even above your desired reading speed. This is to really make sure that your eyes get proper push out of its comfort zone.

Ok? 6 seconds for this… Go!

For the rest of the training, it is critical to study in the perfect format in order to best grasp the technique. Click the button below to download the PDF document to your own device!

McKinsey PST Speed Training – Fast Reading Guide

Market Sizing Example

By Don Truong August 24, 2016Case InterviewOne Comment

Market Sizing Example

By Don Truong | Case Interview | One Comment

Market-sizing Case Example

In the Market-sizing & Guesstimate article, we talked about the two types of problems in general and the 4 overall steps to solve them. I did an end-to-end demonstration of that 4-step approach in a video, too. Now, since this is a HUGE topic with so much demand, how do I add even more insights to help you best prepare for it in case interviews?

Turns out that, most of the time, you will see market-sizing questions in consulting case interviews, not guesstimate ones. So let’s do another article that deep dive into just Market-sizing. I write this in the spirit that you already grasp the basic 4-step approach in the previous article. So if you haven’t done so, please go to that MS-Guesstimate article. There’s a very nice video there to enhance your learning.

Let’s do this with a Market Sizing Example

The question is: What’s the global market size for smartphones?

In general, the approach for market-sizing question still goes through 4 steps like guesstimate. But there are a few more tips & tricks along the way. Let’s dive into this.

Step 1: Clarify 2 things…

Usually in market-sizing questions, there are two things you have to make clear. Sometimes, the question is clear by itself. But expect that most of the time we will have to run through these clarifications. It may seem like taking away time from you, but this is a great and easy way to score points and buy some legal time for your subconscious brain to work on the problem (while the conscious part is doing the talking with the interviewer).

– We have to size the market, so what exactly is the market? What’s the product? Who are the customers? Are there any limitations or exceptions?

– Once we know the market, how is it measured? What’s the timeframe? Do we measure it by dollar value or by number of products? Etc.

Let’s plug these into the example. Here are a few clarification questions I would ask:

– What’s “smartphone” defined as? Is it any phone with a multi-touch screen?

– Does this apply extensively to every people on Earth?

– What’s the unit of measurement? Number of new phones per year? Or the total revenue of new smartphone sales in a year?

Step 2: Break down the problem

For the sake of this example, let’s assume that for those above clarification questions, smartphones are any phone with multi-application capability; the market includes every person on Earth; and it’s measured by annual revenue of new sales.

Now with step 2, the logic behind it is that: you can’t eat an elephant whole. But if you cut it into pieces and eat them one at a time, yes, you can eat an elephant.

Ideally, the best breaking down method gives you the bite-size pieces that everybody can easily estimate. Sometimes this is really hard and we still have to get through those “not-so-bitable” pieces. But if the whole structure is MECE and those “not-so-bitable” pieces are still easier to bite than the original big problem, you will be fine.

Now how do we break down market-sizing problems?

There are three most popular methods: (1) by demand, (2) by supply, and (3) by segment

Each question has its own best method and you need to choose. Let’s demonstrate them through this example. Let’s say I wanna tackle the global smartphone market size problem. Let’s run them through each and every of the three methods.

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Step 2 – Method (1) by demand:

Market size in sales of new phone:

  • Number of new phones sold
    • Phones sold to first-time users
    • Phones sold to people to replace old ones
  • Average price per phone

Step 2 – Method (2) by supply:

Market size in sales of new phones:

  • How many new phones Apple sells
  • How many new phones Samsung sells
  • How many new phones HTC …
  • Sony …
  • Asus …
  • Other small producers

Step 2 – Method (3) by segment:

There are many ways to segment. But one of the most popular ones in the smartphone industry is high-end, mid-end, and low-end.

Market size in sales of new phones:

  • How many new high-end smartphones are sold
  • How many new mid-end smartphones are sold
  • How many new low-end smartphones are sold

When all of these are written down, they seem long. But those can actually happen really fast in our head. We get the general idea about it, then quickly realize which method is the best. In this question, structuring by demand makes the most sense. Let’s demonstrate the details in the following Step 3 & 4.

Step 3 & 4: Go out and hunt down the answer

Branch (1): How many phones are sold each year

  • Branch 1.1: Phones sold to first-time users
    • There are 7 billion people in the world.
    • Suppose people are evenly distributed through all ages.
    • Suppose the average life expectancy is 70 years.
    • So each year, there are 7 billion / 70 = 100 million people getting into the appropriate age to own a phone
    • Suppose 40% of people in the world have a smartphone.
    • All of those come down to 40 million new smartphones sold to first-time users.
  • Branch 1.2: Phone sold to people to replace their old ones:
    • Using the assumptions above, we know 40% of 7 billion people are currently using smartphones. That is 2.8 billion
    • Suppose on average, each person uses a smartphone for 5 years.
    • With all of those, we have 2.8 billion / 5 years = 560 million new smartphones sold to people to replace their old phones.

Consolidating branch 1.1 and 1.2, we have 600 million new smartphones sold each year.

Branch (2): Average price per phone

Suppose the average price per new smartphone is $400

Consolidate both branches, we can estimate the global market size for smartphones is 600 mil x $400 = $240 billion.


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