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Data Scientist & Tech Writer @KDnuggets @DataCamp @Medium | Outstand using data - Data Science, AI and Tech | Join 6k data professionals on https://t.co/VdsUvb9SKu ๐Ÿงฉ
Dec 21, 2024 โ€ข 13 tweets โ€ข 4 min read
Logistic Regression clearly explained ๐Ÿ‘‡๐Ÿป Image 1๏ธโƒฃ ๐—Ÿ๐—ข๐—š๐—œ๐—ฆ๐—ง๐—œ๐—– ๐—ฅ๐—˜๐—š๐—ฅ๐—˜๐—ฆ๐—ฆ๐—œ๐—ข๐—ก
It is a binary classification model used to classify our input data into two main categories.

It can be extended to multiple classifications... but today we'll focus on a binary one.

Also known as Simple Logistic Regression. Image
Dec 18, 2024 โ€ข 12 tweets โ€ข 4 min read
Linear Regression clearly explained ๐Ÿ‘‡๐Ÿป Image Linear regression is the simplest statistical regression method used for predictive analysis.

It can be performed with multiple variables.... but today we'll focus on a single one.

Also known as Simple Linear Regression.
Dec 3, 2024 โ€ข 19 tweets โ€ข 4 min read
๐Ÿš€ New to SQL?

Hereโ€™s a roadmap to get you started, step-by-step! ๐Ÿงต๐Ÿ‘‡

(Don't forget to bookmark for later!! ๐Ÿ˜‰ ) Image 1. ๐—Ÿ๐—ฒ๐—ฎ๐—ฟ๐—ป๐—ถ๐—ป๐—ด ๐˜๐—ต๐—ฒ ๐—•๐—ฎ๐˜€๐—ถ๐—ฐ๐˜€
Before diving deep, it's essential to grasp what is SQL.

Begin with:
โ€ข What is a Relational Database?
โ€ข Comparing SQL and NoSQL Databases
โ€ข Understanding SQL Syntax and Basic Commands
Nov 11, 2024 โ€ข 10 tweets โ€ข 4 min read
How Python work in our computer clearly explained๐Ÿ‘‡๐Ÿป Image 1๏ธโƒฃ ๐— ๐—ฒ๐—บ๐—ผ๐—ฟ๐˜† ๐—ฆ๐—ต๐—ฒ๐—น๐˜ƒ๐—ฒ๐˜€: ๐—ช๐—ต๐—ฒ๐—ฟ๐—ฒ ๐—ฃ๐˜†๐˜๐—ต๐—ผ๐—ป ๐—ฆ๐˜๐—ผ๐—ฟ๐—ฒ๐˜€ ๐——๐—ฎ๐˜๐—ฎ
Imagine your computer's memory as a vast warehouse of shelves.

Each byte is a slot on these shelves.

Python, with your OS's permission, uses this space for its data and code. ๐Ÿข Image
Nov 10, 2024 โ€ข 13 tweets โ€ข 3 min read
Today let's learn SQL's execution order and its importance ๐Ÿ‘‡๐Ÿป Image 1๏ธโƒฃ ๐—ฆ๐—ค๐—Ÿ ๐—”๐—ฆ ๐—” ๐——๐—˜๐—–๐—Ÿ๐—”๐—ฅ๐—”๐—ง๐—œ๐—ฉ๐—˜ ๐—Ÿ๐—”๐—ก๐—š๐—จ๐—”๐—š๐—˜
๐˜ ๐˜ฐ๐˜ถ ๐˜ต๐˜ฆ๐˜ญ๐˜ญ ๐˜ช๐˜ต ๐˜ธ๐˜ฉ๐˜ข๐˜ต ๐˜บ๐˜ฐ๐˜ถ ๐˜ธ๐˜ข๐˜ฏ๐˜ต, ๐˜ฏ๐˜ฐ๐˜ต ๐˜ฉ๐˜ฐ๐˜ธ ๐˜ต๐˜ฐ ๐˜ฅ๐˜ฐ ๐˜ช๐˜ต.

So SQL expects statements to be written in a specific orderโ€Š...

but their evaluation sequence differs. Image
Nov 9, 2024 โ€ข 10 tweets โ€ข 4 min read
SQL Joins clearly explained ๐Ÿ‘‡๐Ÿป Image 1๏ธโƒฃ ๐—Ÿ๐—ฒ๐—ณ๐˜ ๐—๐—ผ๐—ถ๐—ป
Left Join returns all records from the left table (A) and the matched records from the right table (B). If there's no match, the result is NULL on the right side.

๐Ÿ’กThink of it as keeping all items in A and filling gaps from B where they exist. Image
Nov 1, 2024 โ€ข 9 tweets โ€ข 3 min read
Are you the one crafting charts to communicate your data?

Then you better stay with me! ๐Ÿค“

Today let's dive into visual encoding and their key role in DataViz! ๐Ÿ‘‡๐Ÿป Image Charts are composed of two core components:
- Data
- Visuals

But how do we convert this data into a visual representation?

Say hi to visual encodings! ๐Ÿ‘‹๐Ÿป Image
Oct 30, 2024 โ€ข 9 tweets โ€ข 3 min read
Struggling to craft effective charts? ๐Ÿค”๐Ÿ“Š

Let's understand ๐˜„๐—ต๐˜† some charts are ๐—ถ๐—ป๐˜๐˜‚๐—ถ๐˜๐—ถ๐˜ƒ๐—ฒ ๐Ÿ‘‡๐Ÿป Image Think of DataViz as your GPS in the world of numbers.

It turns complex data into clear, actionable insights.

But... why do some charts enlighten us while others don't?

The Gestalt Theory explains how our brains perceive patterns and how to take advantage of them. Image
Oct 30, 2024 โ€ข 16 tweets โ€ข 6 min read
The Transformer's encoder clearly explained ๐Ÿ‘‡๐Ÿป Image 1๏ธโƒฃ ๐—ช๐—›๐—”๐—ง'๐—ฆ ๐—ง๐—›๐—˜ ๐—˜๐—ก๐—–๐—ข๐——๐—˜๐—ฅ? ๐Ÿง 

The Encoder is the part responsible for processing input tokens through self-attention and feed-forward layers to generate context-aware representations.

๐Ÿ‘‰ Itโ€™s the powerhouse behind understanding sequences in NLP models. Image
Oct 28, 2024 โ€ข 10 tweets โ€ข 3 min read
Struggling to craft clear charts? ๐Ÿค”๐Ÿ“Š

Let's understand why some charts are misleading and how to avoid it ๐Ÿ‘‡๐Ÿป Image First things first, ever heard of the term "ink" in data visualization?

It's not about the ink in your pen.

It refers to any part of a visualization that stands out from the background.

Think lines, bars, points, and even text. ๐Ÿ–‹๏ธ Image
Oct 23, 2024 โ€ข 10 tweets โ€ข 3 min read
How to deal with outliers clearly explained ๐Ÿ‘‡๐Ÿป Image 1๏ธโƒฃ ๐—ช๐—ต๐—ฎ๐˜ ๐—ถ๐˜€ ๐—ฎ๐—ป ๐—ผ๐˜‚๐˜๐—น๐—ถ๐—ฒ๐—ฟ?
Outliers are data points that are very different from the rest of the dataset. They are unrepresentative of the overall data. ๐Ÿšจ๐Ÿ“‰ Image
Oct 22, 2024 โ€ข 13 tweets โ€ข 5 min read
Ever felt confused by SQL's execution flow? ๐Ÿค”

Then you better stay with me!

Today let's exemplify SQL's execution order with a simple query๐Ÿ‘‡๐Ÿป Image 1๏ธโƒฃ ๐—ฆ๐—ง๐—”๐—ฅ๐—ง๐—œ๐—ก๐—š ๐—™๐—ฅ๐—ข๐—  ๐—ข๐—จ๐—ฅ ๐—ฅ๐—”๐—ช ๐—ง๐—”๐—•๐—Ÿ๐—˜
We use a dummy table with the salary of employees depending on their field and experience,

๐ŸŽฏ Our main goal?
Understand the field that earns the most. Image
Oct 16, 2024 โ€ข 14 tweets โ€ข 5 min read
The Transformer's decoder clearly explained ๐Ÿ‘‡๐Ÿป Image 1๏ธโƒฃ WHAT'S THE DECODER? ๐ŸŽฏ
The Decoder is the brain behind transforming encoded inputs and previously generated tokens into context-aware outputs.

Imagine it as the artist who paints the final picture from sketches. ๐Ÿ–Œ๏ธ Image
Oct 14, 2024 โ€ข 10 tweets โ€ข 3 min read
The Transformers architecture clearly explained ๐Ÿ‘‡๐Ÿป Image Today I'm starting a new series of threads to simplify the concept of Transformers and what's behind the Natural Language abilities of LLMs.

Let's start with the basics of the Transformer architecture:

The encoder/decoder concept. ๐Ÿง โœจ
Sep 23, 2024 โ€ข 12 tweets โ€ข 4 min read
Support Vector Machine exemplified for dummies ๐Ÿ‘‡๐Ÿป

(Don't forget to save for later ๐Ÿ˜‰) Image 1๏ธโƒฃ GETTING THE DATA
Just like stargazing, we begin by gathering our cosmic data.

Thanks to Kaggle, we have real-world data on pulsar stars.

Now, let's decode this celestial Morse code to predict a star's pulse! ๐Ÿ’ซ๐Ÿ” Image
Sep 20, 2024 โ€ข 14 tweets โ€ข 5 min read
The Transformer's decoder clearly explained ๐Ÿ‘‡๐Ÿป Image 1๏ธโƒฃ WHAT'S THE DECODER? ๐ŸŽฏ
The Decoder is the brain behind transforming encoded inputs and previously generated tokens into context-aware outputs.

Imagine it as the artist who paints the final picture from sketches. ๐Ÿ–Œ๏ธ Image
Sep 18, 2024 โ€ข 16 tweets โ€ข 6 min read
The Transformer's encoder clearly explained ๐Ÿ‘‡๐Ÿป Image 1๏ธโƒฃ ๐—ช๐—›๐—”๐—ง'๐—ฆ ๐—ง๐—›๐—˜ ๐—˜๐—ก๐—–๐—ข๐——๐—˜๐—ฅ? ๐Ÿง 

The Encoder is the part responsible for processing input tokens through self-attention and feed-forward layers to generate context-aware representations.

๐Ÿ‘‰ Itโ€™s the powerhouse behind understanding sequences in NLP models. Image
Sep 16, 2024 โ€ข 15 tweets โ€ข 5 min read
Multiple-class Logistic Regression exemplified for dummies ๐Ÿ‘‡๐Ÿป Image 1๏ธโƒฃ ๐——๐—”๐—ง๐—” ๐—š๐—”๐—ง๐—›๐—˜๐—ฅ๐—œ๐—ก๐—š ๐—ฃ๐—›๐—”๐—ฆ๐—˜

We're using Kaggle to find robust data for our flippered friends.

Meet our stars:
- Iris Setosa
- Iris Versicolor
- Iris Virginica

Like biologists in the wild, we'll use data points to distinguish between them. Image
Sep 15, 2024 โ€ข 12 tweets โ€ข 4 min read
Multiple-class Logistic Regression clearly explained ๐Ÿ‘‡๐Ÿป Image By default, Logistic Regression is like a coin toss - heads or tails, A or B.

But what if you have multiple classes?

That's where we adapt our model for MULTIPLE CHOICES!
There are two main ways:
Jul 28, 2024 โ€ข 10 tweets โ€ข 3 min read
The Transformers architecture clearly explained ๐Ÿ‘‡๐Ÿป Image Today I'm starting a new series of threads to simplify the concept of Transformers and what's behind the Natural Language abilities of LLMs.

Let's start with the basics of the Transformer architecture:

The encoder/decoder concept. ๐Ÿง โœจ
Jul 2, 2024 โ€ข 7 tweets โ€ข 2 min read
Today I am bringing how JOINs work in both SQL and Python๐Ÿ‘‡๐Ÿป Image ๐—ฆ๐—ค๐—Ÿ ๐—ถ๐˜€ ๐—ฟ๐—ฒ๐—ฎ๐—น๐—น๐˜† ๐—ฐ๐—ผ๐—ป๐˜ƒ๐—ฒ๐—ป๐—ถ๐—ฒ๐—ป๐˜ ๐—ณ๐—ผ๐—ฟ ๐—ฑ๐—ฎ๐˜๐—ฎ ๐—ฎ๐—ป๐—ฎ๐—น๐˜†๐˜๐—ถ๐—ฐ๐˜€.

However, there are cases in which the shift towards Python and Pandas is undeniable.

Why?

Pandas can do everything SQL can, and way more.

So let's see how to pass from SQL syntax to Python. Image