Summer of Math Exposition

Presented by 3Blue1Brown 3blue1brown

Why are z-scores so amazing?

Audience:

Tags: statisticsz-scoresnormal-distributions

This video introduces the idea of z-scores as the common language of the normal distribution. We’ll see how measuring values in terms of standard deviations allows us to compare across different normal curves, apply the empirical rule, and ultimately compute probabilities. The z-table then becomes the practical tool that connects these ideas, letting us move between raw data, standardized scores, and areas under the curve. Intended for students in an introductory high school or college statistics course, this video emphasizes understanding the big picture: how z-scores unify the many applications of the normal distribution into a single framework.


Analytics

6 Overall score*
77 Rank
13 Votes
9 Comments

Comments

5

Motivation is clear and the worked examples are easy to follow. Sometimes the text on the screen is identical to the voice-over and doesn’t add to the explanation.

3.8

This video has good content, but it feels like it’s in the wrong order. Instead of opening with the definition, try leading with motivating examples, then building up to a definition once it’s clear what problem the Z-score solves. Also, a tiny bit more time between segments for the viewer to think would go a long way.

4

This video was fine. It wasn’t great, and it wasn’t bad. It came across to me like a bit of a lecture, so my recommendation for future videos is to try to use the power of video as a communication medium to do something that can’t normally be done in a lecture. My second issues is that I felt like this topic was a little bit of “much ado about nothing.” What I mean is that the creator made a big deal about never having to use your calculator to do these complex calculations. But that’s not the full story, because the z-tables are simply calculations that were already performed with a calculator. So it’s not that you don’t need a calculator, it’s that someone has already done the calculations for you.

6

Generally a good video about a topic that is known to be confusing. I think it lacked a bit of motivation and the visual style wasn’t very appealing to me.

5.5

Nice video. Smooth animations and easy to follow. Although since I knew this topic beforehand, I am not sure how beginners would perceive it.

One constructive feedback - the topics could have been explained a bit more slowly in the second half of the video. The pacing was a bit too fast in my opinion. Many animation frames were quickly changing before I could take in all the information on the current slide.

3.5

The concept of the video and the illustrations / animations are really good! The introduction lacks at building the key concepts one after the other and explaining the motivation behind what we do. It starts immediately with the deep concept of a “standard deviation” instead of giving some motivation / example and showing deviation as the “thickness” of the bell curve. This approach will intimidation a new student. Same thing for showing the formula at 1:52. the video doesn’t do anything with it but showing it and talking about calculus can confuse a high school student. Another example is 7:03 not explaining graphically what a “left/right tailed probability” is. As a teacher I would only use this video if the students are well familiar with the key concepts and just need some examples on how the lookup table works.

6.9

Pretty straightforward concepts but presented clearly

6.6

Lucid and clear, useful for students I think

6.2

The weird quality of your audio is a bit distracting, but it’s good enough that it doesn’t distract me too much from the video’s content.

This video is a bit dry, but I now understand its usefulness thanks to your clear explanations. The presentation could be made a bit more memorable with even better graphics and sound quality, but it works well enough like this. The topic isn’t outright novel, but it’s a good math curiosity to know and rehearse. What I also like is that you haven’t just used a theoretical example, but rather an example showcasing that this kind of math is useful in everyday life also.