Want to hear a secret?

Regardless of your experience, here is an area of Machine Learning where you can have a huge impact:

https://abs.twimg.com/emoji/v2/... draggable="false" alt="▫️" title="Weißes kleines Quadrat" aria-label="Emoji: Weißes kleines Quadrat"> Feature Engineering https://abs.twimg.com/emoji/v2/... draggable="false" alt="▫️" title="Weißes kleines Quadrat" aria-label="Emoji: Weißes kleines Quadrat">

It sounds fancy because people love to complicate things, but let& #39;s make it simple: https://abs.twimg.com/emoji/v2/... draggable="false" alt="🧵" title="Thread" aria-label="Emoji: Thread">https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
Want to hear a secret?Regardless of your experience, here is an area of Machine Learning where you can have a huge impact:https://abs.twimg.com/emoji/v2/... draggable= Feature Engineering https://abs.twimg.com/emoji/v2/... draggable="false" alt="▫️" title="Weißes kleines Quadrat" aria-label="Emoji: Weißes kleines Quadrat">It sounds fancy because people love to complicate things, but let& #39;s make it simple: https://abs.twimg.com/emoji/v2/... draggable="false" alt="🧵" title="Thread" aria-label="Emoji: Thread">https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">" title="Want to hear a secret?Regardless of your experience, here is an area of Machine Learning where you can have a huge impact:https://abs.twimg.com/emoji/v2/... draggable="false" alt="▫️" title="Weißes kleines Quadrat" aria-label="Emoji: Weißes kleines Quadrat"> Feature Engineering https://abs.twimg.com/emoji/v2/... draggable="false" alt="▫️" title="Weißes kleines Quadrat" aria-label="Emoji: Weißes kleines Quadrat">It sounds fancy because people love to complicate things, but let& #39;s make it simple: https://abs.twimg.com/emoji/v2/... draggable="false" alt="🧵" title="Thread" aria-label="Emoji: Thread">https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">" class="img-responsive" style="max-width:100%;"/>
In Machine Learning we deal with a lot of data.

Let& #39;s assume we are working with the information of the passengers of the Titanic.

Look at the picture here. That& #39;s what our data looks like.

The goal is to create a model that determines whether a passenger survived.

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
Each one of the columns of our dataset is a "feature."

A Machine Learning algorithm will use these "features" to produce results.

"Feature engineering" is the process that decides which of these features are useful, comes up with new features, or changes the existing ones.

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
The ultimate goal of feature engineering is to feed the Machine Learning algorithm with the best set of features that optimizes the results.

Here is the best part:

https://abs.twimg.com/emoji/v2/... draggable="false" alt="🔹" title="Kleine blaue Raute" aria-label="Emoji: Kleine blaue Raute">Feature Engineering Is An Art https://abs.twimg.com/emoji/v2/... draggable="false" alt="🔹" title="Kleine blaue Raute" aria-label="Emoji: Kleine blaue Raute">

Your creativity plays a huge role here!

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
I& #39;m attaching the list of features again to this tweet.

Look at them, and let& #39;s talk about a couple of examples of how we could transform the data in a way that could produce much better results.

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
https://abs.twimg.com/emoji/v2/... draggable="false" alt="1⃣" title="Tastenkappe Ziffer 1" aria-label="Emoji: Tastenkappe Ziffer 1"> Age

Do you think the age of a passenger has any bearing on whether they survived or not? Probably yes, right?

Do you think that being 27 instead of 28 would make a difference? Probably not.

What matters here is the age group! A child vs. a young person vs. a senior.

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
Instead of feeding our algorithm the age as it comes, we can transform the feature to reflect the age group.

The attached image is just a pseudocode showing a way to create the age group.

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
https://abs.twimg.com/emoji/v2/... draggable="false" alt="2⃣" title="Tastenkappe Ziffer 2" aria-label="Emoji: Tastenkappe Ziffer 2"> Ticket Number

Do you think that the ticket number will make a difference to determine whether a person survived the wreck?

I don& #39;t see how, so we can just drop this particular feature.

What you don& #39;t feed to your algorithm is as important as what you give to it.

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
https://abs.twimg.com/emoji/v2/... draggable="false" alt="3⃣" title="Tastenkappe Ziffer 3" aria-label="Emoji: Tastenkappe Ziffer 3"> Cabin

What do you think about the cabin number?

I think that we mostly care about whether or not the passenger had a cabin regardless of its number.

In this case, we could transform this feature in a simple 0 (doesn& #39;t have a cabin) or 1 (does have a cabin.)

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
Another way to look at this cabin feature:

If the cabin number encodes the floor in the ship where the cabin was located, it would be interesting to retain that information.

(I& #39;m assuming that people on the top floors had a better chance of survival.)

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
https://abs.twimg.com/emoji/v2/... draggable="false" alt="4⃣" title="Tastenkappe Ziffer 4" aria-label="Emoji: Tastenkappe Ziffer 4"> sibsp and parch

These two features tell us the number of siblings + spouses and parents + children respectively.

Does this matter?

Well, here is a theory: people with family on the ship might have had a different chance of survival than those that were traveling alone.

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
Maybe some people couldn& #39;t save themselves because they had to protect others.

Maybe some people survived because others protected them.

Either way, we could combine these two features into a single 0 (no family) or 1 (family) value.

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
Do you get the idea of how the process works?

We started with a set of features, and step by step we have transformed it into something that may give the algorithm a better chance to make good predictions.

This is feature engineering.

https://abs.twimg.com/emoji/v2/... draggable="false" alt="👇" title="Rückhand Zeigefinger nach unten" aria-label="Emoji: Rückhand Zeigefinger nach unten">
Regardless of who you are, and how much experience you have building Machine Learning, "feature engineering" is an area that can get you started in the field.

Here, the best is not whoever knows the most, but whoever is capable of thinking creatively.
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