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Data Science & Machine Learning

Data Science & Machine Learning

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Join this channel to learn data science, artificial intelligence and machine learning with funny quizzes, interesting projects and amazing resources for free For collaborations: @love_data

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๐Ÿ“ˆ Analytical overview of Telegram channel Data Science & Machine Learning

Channel Data Science & Machine Learning (@datasciencefun) in the English language segment is an active participant. Currently, the community unites 75 802 subscribers, ranking 2 117 in the Education category and 4 312 in the India region.

๐Ÿ“Š Audience metrics and dynamics

Since its creation on ะฝะตะฒั–ะดะพะผะพ, the project has demonstrated rapid growth, gathering an audience of 75 802 subscribers.

According to the latest data from 16 June, 2026, the channel demonstrates stable activity. Although there has been a change in the number of participants by 924 over the last 30 days and by 38 over the last 24 hours, overall reach remains high.

  • Verification status: Not verified
  • Engagement rate (ER): The average audience engagement rate is 3.47%. Within the first 24 hours after publication, content typically collects 1.42% reactions from the total number of subscribers.
  • Post reach: On average, each post receives 2 629 views. Within the first day, a publication typically gains 1 075 views.
  • Reactions and interaction: The audience actively supports content: the average number of reactions per post is 5.
  • Thematic interests: Content is focused on key topics such as learning, accuracy, distribution, panda, dataset.

๐Ÿ“ Description and content policy

The author describes the resource as a platform for expressing subjective opinions:
โ€œJoin this channel to learn data science, artificial intelligence and machine learning with funny quizzes, interesting projects and amazing resources for free For collaborations: @love_dataโ€

Thanks to the high frequency of updates (latest data received on 17 June, 2026), the channel maintains relevance and a high level of publication reach. Analytics show that the audience actively interacts with content, making it an important point of influence in the Education category.

75 802
Subscribers
+3824 hours
+2197 days
+92430 days
Posts Archive
The Only roadmap you need to become an ML Engineer ๐Ÿฅณ Phase 1: Foundations (1-2 Months) ๐Ÿ”น Math & Stats Basics โ€“ Linear Algebra, Probability, Statistics ๐Ÿ”น Python Programming โ€“ NumPy, Pandas, Matplotlib, Scikit-Learn ๐Ÿ”น Data Handling โ€“ Cleaning, Feature Engineering, Exploratory Data Analysis Phase 2: Core Machine Learning (2-3 Months) ๐Ÿ”น Supervised & Unsupervised Learning โ€“ Regression, Classification, Clustering ๐Ÿ”น Model Evaluation โ€“ Cross-validation, Metrics (Accuracy, Precision, Recall, AUC-ROC) ๐Ÿ”น Hyperparameter Tuning โ€“ Grid Search, Random Search, Bayesian Optimization ๐Ÿ”น Basic ML Projects โ€“ Predict house prices, customer segmentation Phase 3: Deep Learning & Advanced ML (2-3 Months) ๐Ÿ”น Neural Networks โ€“ TensorFlow & PyTorch Basics ๐Ÿ”น CNNs & Image Processing โ€“ Object Detection, Image Classification ๐Ÿ”น NLP & Transformers โ€“ Sentiment Analysis, BERT, LLMs (GPT, Gemini) ๐Ÿ”น Reinforcement Learning Basics โ€“ Q-learning, Policy Gradient Phase 4: ML System Design & MLOps (2-3 Months) ๐Ÿ”น ML in Production โ€“ Model Deployment (Flask, FastAPI, Docker) ๐Ÿ”น MLOps โ€“ CI/CD, Model Monitoring, Model Versioning (MLflow, Kubeflow) ๐Ÿ”น Cloud & Big Data โ€“ AWS/GCP/Azure, Spark, Kafka ๐Ÿ”น End-to-End ML Projects โ€“ Fraud detection, Recommendation systems Phase 5: Specialization & Job Readiness (Ongoing) ๐Ÿ”น Specialize โ€“ Computer Vision, NLP, Generative AI, Edge AI ๐Ÿ”น Interview Prep โ€“ Leetcode for ML, System Design, ML Case Studies ๐Ÿ”น Portfolio Building โ€“ GitHub, Kaggle Competitions, Writing Blogs ๐Ÿ”น Networking โ€“ Contribute to open-source, Attend ML meetups, LinkedIn presence Follow this advanced roadmap to build a successful career in ML! The data field is vast, offering endless opportunities so start preparing now.

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๐Ÿ“Œ Roadmap to Master Machine Learning in 6 Steps Whether you're just starting or looking to go pro in ML, this roadmap will k
๐Ÿ“Œ Roadmap to Master Machine Learning in 6 Steps Whether you're just starting or looking to go pro in ML, this roadmap will keep you on track: 1๏ธโƒฃ Learn the Fundamentals Build a math foundation (algebra, calculus, stats) + Python + libraries like NumPy & Pandas 2๏ธโƒฃ Learn Essential ML Concepts Start with supervised learning (regression, classification), then unsupervised learning (K-Means, PCA) 3๏ธโƒฃ Understand Data Handling Clean, transform, and visualize data effectively using summary stats & feature engineering 4๏ธโƒฃ Explore Advanced Techniques Delve into ensemble methods, CNNs, deep learning, and NLP fundamentals 5๏ธโƒฃ Learn Model Deployment Use Flask, FastAPI, and cloud platforms (AWS, GCP) for scalable deployment 6๏ธโƒฃ Build Projects & Network Participate in Kaggle, create portfolio projects, and connect with the ML community React โค๏ธ for more

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Machine Learning โ€“ Essential Concepts ๐Ÿš€ 1๏ธโƒฃ Types of Machine Learning Supervised Learning โ€“ Uses labeled data to train models. Examples: Linear Regression, Decision Trees, Random Forest, SVM Unsupervised Learning โ€“ Identifies patterns in unlabeled data. Examples: Clustering (K-Means, DBSCAN), PCA Reinforcement Learning โ€“ Models learn through rewards and penalties. Examples: Q-Learning, Deep Q Networks 2๏ธโƒฃ Key Algorithms Regression โ€“ Predicts continuous values (Linear Regression, Ridge, Lasso). Classification โ€“ Categorizes data into classes (Logistic Regression, Decision Tree, SVM, Naรฏve Bayes). Clustering โ€“ Groups similar data points (K-Means, Hierarchical Clustering, DBSCAN). Dimensionality Reduction โ€“ Reduces the number of features (PCA, t-SNE, LDA). 3๏ธโƒฃ Model Training & Evaluation Train-Test Split โ€“ Dividing data into training and testing sets. Cross-Validation โ€“ Splitting data multiple times for better accuracy. Metrics โ€“ Evaluating models with RMSE, Accuracy, Precision, Recall, F1-Score, ROC-AUC. 4๏ธโƒฃ Feature Engineering Handling missing data (mean imputation, dropna()). Encoding categorical variables (One-Hot Encoding, Label Encoding). Feature Scaling (Normalization, Standardization). 5๏ธโƒฃ Overfitting & Underfitting Overfitting โ€“ Model learns noise, performs well on training but poorly on test data. Underfitting โ€“ Model is too simple and fails to capture patterns. Solution: Regularization (L1, L2), Hyperparameter Tuning. 6๏ธโƒฃ Ensemble Learning Combining multiple models to improve performance. Bagging (Random Forest) Boosting (XGBoost, Gradient Boosting, AdaBoost) 7๏ธโƒฃ Deep Learning Basics Neural Networks (ANN, CNN, RNN). Activation Functions (ReLU, Sigmoid, Tanh). Backpropagation & Gradient Descent. 8๏ธโƒฃ Model Deployment Deploy models using Flask, FastAPI, or Streamlit. Model versioning with MLflow. Cloud deployment (AWS SageMaker, Google Vertex AI).

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SQL Zero to Hero โœ…
SQL Zero to Hero โœ…

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Data Science Essential Libraries โœ…
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Data Analytics Interview Preparation [Questions with Answers] How did you get your job? I was hired after an internship.  To get the internship, I prepared a bunch for general Python questions (LeetCode etc.) and studied the basics of machine learning (several different algorithms, how they work, when they're useful, metrics  to measure their performance, how to train them in practice etc.).  To get the internship I had to pass a technical interview as well as a take-home machine learning (ML) exercise. Then, it was just a question of doing a good job in the internship!  What are your data related responsibilities in your job?  I work on our recommendation system. Itโ€™s deep learning based. I work on a lot of features to try and  improve it (reinforcement learning & NLP etc). Since I'm in a start-up, it's also up to our team to put the models we design into production. So, after a phase of research & development and model design, in notebooks, it's time to create a real pipeline, by creating scripts.  This enables us to define, train, replace, compare and check the status of the models in production. It's basically all in Python, using Keras/TensorFlow, Pandas, Scikit-learn and NumPy. We also do a lot of analysis for the business team to help them compute metrics of interest (related to  revenue, acquisition etc.). For that, we use an external utility called Metabase. It is is hooked up to our database where we write SQL queries and visualize the results and create dashboards (using  Tableau/Looker etc).  I would say my role is quite "full-stack" since we are all involved from the phase of R&D to deployment on our cluster.  Was it difficult to get this role? I got hired after an internship. If you come from a scientific background, it's not that hard to transition into data science. All the math is something you will probably have seen already (especially if you're  doing maths or physics). So, with some preparation and coding practice, you can start applying to internships.  It took me maybe a month or two of preparation to get some basic ideas of the typical Python data stack (Pandas, Keras, SciKit-learn etc) before I started to send out CVs. Then, if you get an internship, try your best to do the best you can and then maybe you'll be hired after!

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Hey guys, Today, letโ€™s talk about SQL conceptual questions that are often asked in data analyst interviews. These questions test not only your technical skills but also your conceptual understanding of SQL and its real-world applications. 1. What is the difference between SQL and NoSQL? - SQL (Structured Query Language) is a relational database management system, meaning it uses tables (rows and columns) to store data. - NoSQL databases, on the other hand, handle unstructured data and donโ€™t rely on a schema, making them more flexible in terms of data storage and retrieval. - Interview Tip: Don't just memorize definitions. Be prepared to explain scenarios where youโ€™d use SQL over NoSQL, and vice versa. 2. What is the difference between INNER JOIN and OUTER JOIN? - An INNER JOIN returns records that have matching values in both tables. - An OUTER JOIN returns all records from one table and the matched records from the second table. If there's no match, NULL values are returned. 3. How do you optimize a SQL query for better performance? - Indexing: Create indexes on columns used frequently in WHERE, JOIN, or GROUP BY clauses. - Query optimization: Use appropriate WHERE clauses to reduce the data set and avoid unnecessary calculations. - Avoid SELECT *: Always specify the columns you need to reduce the amount of data retrieved. - Limit results: If you only need a subset of the data, use the LIMIT clause. 4. What are the different types of SQL constraints? Constraints are used to enforce rules on data in a table. They ensure the accuracy and reliability of the data. The most common types are: - PRIMARY KEY: Ensures each record is unique and not null. - FOREIGN KEY: Enforces a relationship between two tables. - UNIQUE: Ensures all values in a column are unique. - NOT NULL: Prevents NULL values from being entered into a column. - CHECK: Ensures a column's values meet a specific condition. 5. What is normalization? What are the different normal forms? Normalization is the process of organizing data to reduce redundancy and improve data integrity. Hereโ€™s a quick overview of normal forms: - 1NF (First Normal Form): Ensures that all values in a table are atomic (indivisible). - 2NF (Second Normal Form): Ensures that the table is in 1NF and that all non-key columns are fully dependent on the primary key. - 3NF (Third Normal Form): Ensures that the table is in 2NF and all columns are independent of each other except for the primary key. 6. What is a subquery? A subquery is a query within another query. It's used to perform operations that need intermediate results before generating the final query. Example:
SELECT employee_id, name
FROM employees
WHERE salary > (SELECT AVG(salary) FROM employees);
In this case, the subquery calculates the average salary, and the outer query selects employees whose salary is greater than the average. 7. What is the difference between a UNION and a UNION ALL? - UNION combines the result sets of two SELECT statements and removes duplicates. - UNION ALL combines the result sets and includes duplicates. 8. What is the difference between WHERE and HAVING clause? - WHERE filters rows before any groupings are made. Itโ€™s used with SELECT, INSERT, UPDATE, or DELETE statements. - HAVING filters groups after the GROUP BY clause. 9. How would you handle NULL values in SQL? NULL values can represent missing or unknown data. Hereโ€™s how to manage them: - Use IS NULL or IS NOT NULL in WHERE clauses to filter null values. - Use COALESCE() or IFNULL() to replace NULL values with default ones. Example:
SELECT name, COALESCE(age, 0) AS age
FROM employees;
10. What is the purpose of the GROUP BY clause? The GROUP BY clause groups rows with the same values into summary rows. Itโ€™s often used with aggregate functions like COUNT, SUM, AVG, etc. Example:
SELECT department, COUNT(*)
FROM employees
GROUP BY department;