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SQL interview questions with answers 😄👇
1. Question: What is SQL?
Answer: SQL (Structured Query Language) is a programming language designed for managing and manipulating relational databases. It is used to query, insert, update, and delete data in databases.
2. Question: Differentiate between SQL and MySQL.
Answer: SQL is a language for managing relational databases, while MySQL is an open-source relational database management system (RDBMS) that uses SQL as its language.
3. Question: Explain the difference between INNER JOIN and LEFT JOIN.
Answer: INNER JOIN returns rows when there is a match in both tables, while LEFT JOIN returns all rows from the left table and the matched rows from the right table, filling in with NULLs for non-matching rows.
4. Question: How do you remove duplicate records from a table?
Answer: Use the DISTINCT
keyword in a SELECT
statement to retrieve unique records. For example: SELECT DISTINCT column1, column2 FROM table;
5. Question: What is a subquery in SQL?
Answer: A subquery is a query nested inside another query. It can be used to retrieve data that will be used in the main query as a condition to further restrict the data to be retrieved.
6. Question: Explain the purpose of the GROUP BY clause.
Answer: The GROUP BY clause is used to group rows that have the same values in specified columns into summary rows, like when using aggregate functions such as COUNT, SUM, AVG, etc.
7. Question: How can you add a new record to a table?
Answer: Use the INSERT INTO
statement. For example: INSERT INTO table_name (column1, column2) VALUES (value1, value2);
8. Question: What is the purpose of the HAVING clause?
Answer: The HAVING clause is used in combination with the GROUP BY clause to filter the results of aggregate functions based on a specified condition.
9. Question: Explain the concept of normalization in databases.
Answer: Normalization is the process of organizing data in a database to reduce redundancy and improve data integrity. It involves breaking down tables into smaller, related tables.
10. Question: How do you update data in a table in SQL?
Answer: Use the UPDATE
statement to modify existing records in a table. For example: UPDATE table_name SET column1 = value1 WHERE condition;
Tableau Cheat Sheet ✅
This Tableau cheatsheet is designed to be your quick reference guide for data visualization and analysis using Tableau. Whether you’re a beginner learning the basics or an experienced user looking for a handy resource, this cheatsheet covers essential topics.
1. Connecting to Data
- Use *Connect* pane to connect to various data sources (Excel, SQL Server, Text files, etc.).
2. Data Preparation
- Data Interpreter: Clean data automatically using the Data Interpreter.
- Join Data: Combine data from multiple tables using joins (Inner, Left, Right, Outer).
- Union Data: Stack data from multiple tables with the same structure.
3. Creating Views
- Drag & Drop: Drag fields from the Data pane onto Rows, Columns, or Marks to create visualizations.
- Show Me: Use the *Show Me* panel to select different visualization types.
4. Types of Visualizations
- Bar Chart: Compare values across categories.
- Line Chart: Display trends over time.
- Pie Chart: Show proportions of a whole (use sparingly).
- Map: Visualize geographic data.
- Scatter Plot: Show relationships between two variables.
5. Filters
- Dimension Filters: Filter data based on categorical values.
- Measure Filters: Filter data based on numerical values.
- Context Filters: Set a context for other filters to improve performance.
6. Calculated Fields
- Create calculated fields to derive new data:
- Example: Sales Growth = SUM([Sales]) - SUM([Previous Sales])
7. Parameters
- Use parameters to allow user input and control measures dynamically.
8. Formatting
- Format fonts, colors, borders, and lines using the Format pane for better visual appeal.
9. Dashboards
- Combine multiple sheets into a dashboard using the *Dashboard* tab.
- Use dashboard actions (filter, highlight, URL) to create interactivity.
10. Story Points
- Create a story to guide users through insights with narrative and visualizations.
11. Publishing & Sharing
- Publish dashboards to Tableau Server or Tableau Online for sharing and collaboration.
12. Export Options
- Export to PDF or image for offline use.
13. Keyboard Shortcuts
- Show/Hide Sidebar: Ctrl+Alt+T
- Duplicate Sheet: Ctrl + D
- Undo: Ctrl + Z
- Redo: Ctrl + Y
14. Performance Optimization
- Use extracts instead of live connections for faster performance.
- Optimize calculations and filters to improve dashboard loading times.
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When preparing for an SQL project-based interview, the focus typically shifts from theoretical knowledge to practical application. Here are some SQL project-based interview questions that could help assess your problem-solving skills and experience:
1. Database Design and Schema
- Question: Describe a database schema you have designed in a past project. What were the key entities, and how did you establish relationships between them?
- Follow-Up: How did you handle normalization? Did you denormalize any tables for performance reasons?
2. Data Modeling
- Question: How would you model a database for an e-commerce application? What tables would you include, and how would they relate to each other?
- Follow-Up: How would you design the schema to handle scenarios like discount codes, product reviews, and inventory management?
3. Query Optimization
- Question: Can you discuss a time when you optimized an SQL query? What was the original query, and what changes did you make to improve its performance?
- Follow-Up: What tools or techniques did you use to identify and resolve the performance issues?
4. ETL Processes
- Question: Describe an ETL (Extract, Transform, Load) process you have implemented. How did you handle data extraction, transformation, and loading?
- Follow-Up: How did you ensure data quality and consistency during the ETL process?
5. Handling Large Datasets
- Question: In a project where you dealt with large datasets, how did you manage performance and storage issues?
- Follow-Up: What indexing strategies or partitioning techniques did you use?
6. Joins and Subqueries
- Question: Provide an example of a complex query you wrote involving multiple joins and subqueries. What was the business problem you were solving?
- Follow-Up: How did you ensure that the query performed efficiently?
7. Stored Procedures and Functions
- Question: Have you created stored procedures or functions in any of your projects? Can you describe one and explain why you chose to encapsulate the logic in a stored procedure?
- Follow-Up: How did you handle error handling and logging within the stored procedure?
8. Data Integrity and Constraints
- Question: How did you enforce data integrity in your SQL projects? Can you give examples of constraints (e.g., primary keys, foreign keys, unique constraints) you implemented?
- Follow-Up: How did you handle situations where constraints needed to be temporarily disabled or modified?
9. Version Control and Collaboration
- Question: How did you manage database version control in your projects? What tools or practices did you use to ensure collaboration with other developers?
- Follow-Up: How did you handle conflicts or issues arising from multiple developers working on the same database?
10. Data Migration
- Question: Describe a data migration project you worked on. How did you ensure that the migration was successful, and what steps did you take to handle data inconsistencies or errors?
- Follow-Up: How did you test the migration process before moving to the production environment?
11. Security and Permissions
- Question: In your SQL projects, how did you manage database security?
- Follow-Up: How did you handle encryption or sensitive data within the database?
12. Handling Unstructured Data
- Question: Have you worked with unstructured or semi-structured data in an SQL environment?
- Follow-Up: What challenges did you face, and how did you overcome them?
13. Real-Time Data Processing
- Question: Can you describe a project where you handled real-time data processing using SQL? What were the key challenges, and how did you address them?
- Follow-Up: How did you ensure the performance and reliability of the real-time data processing system?
Be prepared to discuss specific examples from your past work and explain your thought process in detail.
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Top 20 AI Concepts You Should Know
1 - Machine Learning: Core algorithms, statistics, and model training techniques.
2 - Deep Learning: Hierarchical neural networks learning complex representations automatically.
3 - Neural Networks: Layered architectures efficiently model nonlinear relationships accurately.
4 - NLP: Techniques to process and understand natural language text.
5 - Computer Vision: Algorithms interpreting and analyzing visual data effectively
6 - Reinforcement Learning: Distributed traffic across multiple servers for reliability.
7 - Generative Models: Creating new data samples using learned data.
8 - LLM: Generates human-like text using massive pre-trained data.
9 - Transformers: Self-attention-based architecture powering modern AI models.
10 - Feature Engineering: Designing informative features to improve model performance significantly.
11 - Supervised Learning: Learns useful representations without labeled data.
12 - Bayesian Learning: Incorporate uncertainty using probabilistic model approaches.
13 - Prompt Engineering: Crafting effective inputs to guide generative model outputs.
14 - AI Agents: Autonomous systems that perceive, decide, and act.
15 - Fine-Tuning Models: Customizes pre-trained models for domain-specific tasks.
16 - Multimodal Models: Processes and generates across multiple data types like images, videos, and text.
17 - Embeddings: Transforms input into machine-readable vector formats.
18 - Vector Search: Finds similar items using dense vector embeddings.
19 - Model Evaluation: Assessing predictive performance using validation techniques.
20 - AI Infrastructure: Deploying scalable systems to support AI operations.
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Читать полностью…Essential Topics to Master Data Analytics Interviews: 🚀
SQL:
1. Foundations
- SELECT statements with WHERE, ORDER BY, GROUP BY, HAVING
- Basic JOINS (INNER, LEFT, RIGHT, FULL)
- Navigate through simple databases and tables
2. Intermediate SQL
- Utilize Aggregate functions (COUNT, SUM, AVG, MAX, MIN)
- Embrace Subqueries and nested queries
- Master Common Table Expressions (WITH clause)
- Implement CASE statements for logical queries
3. Advanced SQL
- Explore Advanced JOIN techniques (self-join, non-equi join)
- Dive into Window functions (OVER, PARTITION BY, ROW_NUMBER, RANK, DENSE_RANK, lead, lag)
- Optimize queries with indexing
- Execute Data manipulation (INSERT, UPDATE, DELETE)
Python:
1. Python Basics
- Grasp Syntax, variables, and data types
- Command Control structures (if-else, for and while loops)
- Understand Basic data structures (lists, dictionaries, sets, tuples)
- Master Functions, lambda functions, and error handling (try-except)
- Explore Modules and packages
2. Pandas & Numpy
- Create and manipulate DataFrames and Series
- Perfect Indexing, selecting, and filtering data
- Handle missing data (fillna, dropna)
- Aggregate data with groupby, summarizing data
- Merge, join, and concatenate datasets
3. Data Visualization with Python
- Plot with Matplotlib (line plots, bar plots, histograms)
- Visualize with Seaborn (scatter plots, box plots, pair plots)
- Customize plots (sizes, labels, legends, color palettes)
- Introduction to interactive visualizations (e.g., Plotly)
Excel:
1. Excel Essentials
- Conduct Cell operations, basic formulas (SUMIFS, COUNTIFS, AVERAGEIFS, IF, AND, OR, NOT & Nested Functions etc.)
- Dive into charts and basic data visualization
- Sort and filter data, use Conditional formatting
2. Intermediate Excel
- Master Advanced formulas (V/XLOOKUP, INDEX-MATCH, nested IF)
- Leverage PivotTables and PivotCharts for summarizing data
- Utilize data validation tools
- Employ What-if analysis tools (Data Tables, Goal Seek)
3. Advanced Excel
- Harness Array formulas and advanced functions
- Dive into Data Model & Power Pivot
- Explore Advanced Filter, Slicers, and Timelines in Pivot Tables
- Create dynamic charts and interactive dashboards
Power BI:
1. Data Modeling in Power BI
- Import data from various sources
- Establish and manage relationships between datasets
- Grasp Data modeling basics (star schema, snowflake schema)
2. Data Transformation in Power BI
- Use Power Query for data cleaning and transformation
- Apply advanced data shaping techniques
- Create Calculated columns and measures using DAX
3. Data Visualization and Reporting in Power BI
- Craft interactive reports and dashboards
- Utilize Visualizations (bar, line, pie charts, maps)
- Publish and share reports, schedule data refreshes
Statistics Fundamentals:
- Mean, Median, Mode
- Standard Deviation, Variance
- Probability Distributions, Hypothesis Testing
- P-values, Confidence Intervals
- Correlation, Simple Linear Regression
- Normal Distribution, Binomial Distribution, Poisson Distribution.
Show some ❤️ if you're ready to elevate your data analytics journey! 📊
ENJOY LEARNING 👍👍
What are the differences between a Power BI dataset, a Report, and a Dashboard?
In Power BI:
1. Dataset: It's where your raw data resides. Think of it as your data source. You import or connect to data, transform it, and then store it in a dataset within Power BI.
2. Report: Reports visualize data from your dataset. They consist of visuals like charts, graphs, tables, etc., created using the data in your dataset. Reports allow you to explore and analyze your data in depth.
3. Dashboard: Dashboards are a collection of visuals from one or more reports, designed to give a snapshot view of your data. They provide a high-level overview of key metrics and trends. You can pin visuals from different reports onto a dashboard to create a unified view.
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Being a Generalist Data Scientist won't get you hired.
Here is how you can specialize 👇
Companies have specific problems that require certain skills to solve. If you do not know which path you want to follow. Start broad first, explore your options, then specialize.
To discover what you enjoy the most, try answering different questions for each DS role:
- 𝐌𝐚𝐜𝐡𝐢𝐧𝐞 𝐋𝐞𝐚𝐫𝐧𝐢𝐧𝐠 𝐄𝐧𝐠𝐢𝐧𝐞𝐞𝐫
Qs:
“How should we monitor model performance in production?”
- 𝐃𝐚𝐭𝐚 𝐀𝐧𝐚𝐥𝐲𝐬𝐭 / 𝐏𝐫𝐨𝐝𝐮𝐜𝐭 𝐃𝐚𝐭𝐚 𝐒𝐜𝐢𝐞𝐧𝐭𝐢𝐬𝐭
Qs:
“How can we visualize customer segmentation to highlight key demographics?”
- 𝐃𝐚𝐭𝐚 𝐒𝐜𝐢𝐞𝐧𝐭𝐢𝐬𝐭
Qs:
“How can we use clustering to identify new customer segments for targeted marketing?”
- 𝐌𝐚𝐜𝐡𝐢𝐧𝐞 𝐋𝐞𝐚𝐫𝐧𝐢𝐧𝐠 𝐑𝐞𝐬𝐞𝐚𝐫𝐜𝐡𝐞𝐫
Qs:
“What novel architectures can we explore to improve model robustness?”
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Qs:
“How can we automate the deployment of machine learning models to ensure continuous integration and delivery?”
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COMMON TERMINOLOGIES IN PYTHON - PART 1
Have you ever gotten into a discussion with a programmer before? Did you find some of the Terminologies mentioned strange or you didn't fully understand them?
In this series, we would be looking at the common Terminologies in python.
It is important to know these Terminologies to be able to professionally/properly explain your codes to people and/or to be able to understand what people say in an instant when these codes are mentioned. Below are a few:
IDLE (Integrated Development and Learning Environment) - this is an environment that allows you to easily write Python code. IDLE can be used to execute a single statements and create, modify, and execute Python scripts.
Python Shell - This is the interactive environment that allows you to type in python code and execute them immediately
System Python - This is the version of python that comes with your operating system
Prompt - usually represented by the symbol ">>>" and it simply means that python is waiting for you to give it some instructions
REPL (Read-Evaluate-Print-Loop) - this refers to the sequence of events in your interactive window in form of a loop (python reads the code inputted>the code is evaluated>output is printed)
Argument - this is a value that is passed to a function when called eg print("Hello World")... "Hello World" is the argument that is being passed.
Function - this is a code that takes some input, known as arguments, processes that input and produces an output called a return value. E.g print("Hello World")... print is the function
Return Value - this is the value that a function returns to the calling script or function when it completes its task (in other words, Output). E.g.
>>> print("Hello World")
Hello World
Where Hello World is your return value.
Note: A return value can be any of these variable types: handle, integer, object, or string
Script - This is a file where you store your python code in a text file and execute all of the code with a single command
Script files - this is a file containing a group of python scripts
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Top 10 Data Science Concepts You Should Know 🧠
1. Data Cleaning: Garbage In, Garbage Out. You can't build great models on messy data. Learn to spot and fix errors before you start. Seriously, this is the most important step.
2. EDA: Your Data's Secret Diary. Before you build anything, EXPLORE! Understand your data's quirks, distributions, and relationships. Visualizations are your best friend here.
3. Feature Engineering: Turning Data into Gold. Raw data is often useless. Feature engineering is how you transform it into something your models can actually learn from. Think about what the data represents.
4. Machine Learning: The Right Tool for the Job. Don't just throw algorithms at problems. Understand why you're using linear regression vs. a random forest.
5. Model Validation: Are You Lying to Yourself? Too many people build models that look great on paper but fail in the real world. Rigorous validation is essential.
6. Feature Selection: Less Can Be More. Get rid of the noise! Focusing on the most important features improves performance and interpretability.
7. Dimensionality Reduction: Simplify, Simplify, Simplify. High-dimensional data can be a nightmare. Learn techniques to reduce complexity without losing valuable information.
8. Model Optimization: Squeeze Every Last Drop. Fine-tuning your model parameters can make a huge difference. But be careful not to overfit!
9. Data Visualization: Tell a Story People Understand. Don't just dump charts on a page. Craft a narrative that highlights key insights.
10. Big Data: When Things Get Serious. If you're dealing with massive datasets, you'll need specialized tools like Hadoop and Spark. But don't start here! Master the fundamentals first.
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• Train/Test Split: Dividing data into training and testing sets.
• Cross-Validation: Evaluating model performance robustly.
• Overfitting and Underfitting: Understanding and mitigating these issues.
• Bias-Variance Tradeoff: Understanding the balance between model complexity and generalization ability.
V. Communication and Presentation:
• Data Storytelling: Crafting a narrative around your data findings.
• Visualization Best Practices: Choosing the right chart types, designing clear and effective visuals.
• Presentation Skills: Presenting your findings clearly and concisely to both technical and non-technical audiences.
• Report Writing: Documenting your analysis and findings in a clear and organized manner.
VI. Essential Soft Skills:
• Critical Thinking: Analyzing problems and formulating solutions.
• Communication: Explaining complex concepts clearly.
• Problem-Solving: Identifying and addressing data-related challenges.
• Teamwork: Collaborating effectively with others.
• Curiosity: A desire to learn and explore new data and techniques.
VII. Ethical Considerations:
• Data Privacy Understanding regulations like GDPR and CCPA.
• Bias Detection and Mitigation Ensuring your models are fair and unbiased.
• Transparency and Explainability Being able to explain how your models make decisions.
How to Learn:
• Online Courses: Coursera, edX, Udacity, DataCamp.
• Books: "Hands-On Machine Learning with Scikit-Learn, Keras & TensorFlow" by Aurélien Géron, "Python Data Science Handbook" by Jake VanderPlas.
• Kaggle: Practice on real-world datasets.
• Personal Projects: Apply your knowledge to projects that interest you.
• Community: Engage with other data scientists online and in person.
This is a comprehensive list, and you don't need to master everything immediately.
Focus on building a strong foundation in the core areas, and you can gradually expand your knowledge and skills over time.
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Читать полностью…20 Must-Know Statistics Questions for Data Analyst and Business Analyst Roles (With Detailed Answers)
1. What is the difference between descriptive and inferential statistics?
Descriptive statistics summarize and organize data (e.g., mean, median, mode).
Inferential statistics make predictions or inferences about a population based on a sample (e.g., hypothesis testing, confidence intervals).
2. Explain mean, median, and mode and when to use each.
Mean is the average; use when data is symmetrically distributed.
Median is the middle value; best when data has outliers.
Mode is the most frequent value; useful for categorical data.
3. What is standard deviation, and why is it important?
It measures data spread around the mean. A low value = less variability; high value = more spread. Important for understanding consistency and risk.
4. Define correlation vs. causation with examples.
Correlation: Two variables move together but don't cause each other (e.g., ice cream sales and drowning).
Causation: One variable directly affects another (e.g., smoking causes lung cancer).
5. What is a p-value, and how do you interpret it?
P-value measures the probability of observing results given that the null hypothesis is true. A small p-value (typically < 0.05) suggests rejecting the null.
6. Explain the concept of confidence intervals.
A range of values used to estimate a population parameter. A 95% CI means there's a 95% chance the true value falls within the range.
7. What are outliers, and how can you handle them?
Outliers are extreme values differing significantly from others. Handle using:
Removal (if due to error)
Transformation
Capping (e.g., winsorizing)
8. When would you use a t-test vs. a z-test?
T-test: Small samples (n < 30) and unknown population standard deviation.
Z-test: Large samples and known standard deviation.
9. What is the Central Limit Theorem (CLT), and why is it important?
CLT states that the sampling distribution of the sample mean approaches a normal distribution as sample size grows, regardless of population distribution. Essential for inference.
10. Explain the difference between population and sample.
Population: Entire group of interest.
Sample: Subset used for analysis. Inference is made from the sample to the population.
11. What is regression analysis, and what are its key assumptions?
Predicts a dependent variable using one or more independent variables.
Assumptions: Linearity, independence, homoscedasticity, no multicollinearity, normality of residuals.
12. How do you calculate probability, and why does it matter in analytics?
Probability = (Favorable outcomes) / (Total outcomes).
Critical for risk estimation, decision-making, and predictions.
13. Explain the concept of Bayes’ Theorem with a practical example.
Bayes’ updates the probability of an event based on new evidence:
P(A|B) = [P(B|A) * P(A)] / P(B)
Example: Calculating disease probability given a positive test result.
14. What is an ANOVA test, and when should it be used?
ANOVA (Analysis of Variance) compares means across 3+ groups to see if at least one differs.
Use when comparing more than two groups.
15. Define skewness and kurtosis in a dataset.
Skewness: Measure of asymmetry (positive = right-skewed, negative = left).
Kurtosis: Measure of tail thickness (high kurtosis = heavy tails, outliers).
16. What is the difference between parametric and non-parametric tests?
Parametric: Assumes data follows a distribution (e.g., t-test).
Non-parametric: No assumptions; use with skewed or ordinal data (e.g., Mann-Whitney U).
17. What are Type I and Type II errors in hypothesis testing?
Type I error: False positive (rejecting a true null).
Type II error: False negative (failing to reject a false null).
18. How do you handle missing data in a dataset?
Methods:
Deletion (listwise or pairwise)
Imputation (mean, median, mode, regression)
Advanced: KNN, MICE
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Data Science Fundamentals You Should Know ☑️
I. Core Mathematics and Statistics:
• Linear Algebra:
• Why: Understanding how algorithms manipulate data as vectors and matrices. Crucial for machine learning.
• Key Concepts: Vectors, matrices, matrix operations (addition, multiplication, transpose, inverse), eigenvalues, eigenvectors, singular value decomposition (SVD).
• Calculus:
• Why: Optimization algorithms (like gradient descent) rely on calculus concepts.
• Key Concepts: Derivatives, integrals, limits, optimization, chain rule.
• Probability and Statistics:
• Why: Data is inherently uncertain. Statistics provides the tools to understand and quantify that uncertainty.
• Key Concepts:
* Descriptive Statistics: Mean, median, mode, variance, standard deviation, percentiles.
* Probability Distributions: Normal, binomial, Poisson, exponential.
* Hypothesis Testing: Null hypothesis, alternative hypothesis, p-values, t-tests, chi-squared tests, ANOVA.
* Confidence Intervals: Estimating population parameters.
* Bayesian Statistics: Bayes' theorem, prior probabilities, posterior probabilities.
• Discrete Mathematics (Optional, but helpful):
* Why: Especially relevant if you're working with graph data or network analysis.
* Key Concepts: Sets, logic, combinatorics, graph theory.
II. Programming Fundamentals:
• Python or R (Choose one to start, Python is often preferred):
• Why: These are the workhorses of data science.
• Key Concepts:
* Data Structures: Lists, dictionaries (Python), vectors, lists (R).
* Control Flow: Loops, conditional statements.
* Functions: Defining and using functions.
* Object-Oriented Programming (OOP) Basics: Classes, objects (helpful, but not essential to start).
• Key Python Libraries:
• NumPy: Numerical computing (arrays, linear algebra).
• Pandas: Data manipulation and analysis (DataFrames).
• Matplotlib & Seaborn: Data visualization.
• Scikit-learn: Machine learning algorithms.
• Key R Libraries:
• dplyr: Data manipulation.
• ggplot2: Data visualization.
• caret: Machine learning.
• SQL:
• Why: Essential for retrieving and manipulating data from databases.
• Key Concepts: SELECT, FROM, WHERE, JOIN, GROUP BY, ORDER BY, aggregate functions.
III. Data Wrangling and Exploration:
• Data Collection:
• Understanding Data Sources: APIs, databases, web scraping (ethical considerations).
• Data Cleaning:
• Handling Missing Values: Imputation strategies.
• Removing Duplicates: Identifying and removing redundant data.
• Correcting Inconsistencies: Standardizing formats, fixing errors.
• Data Transformation:
• Scaling and Normalization: Standardizing numerical features.
• Encoding Categorical Features: One-hot encoding, label encoding.
• Exploratory Data Analysis (EDA):
• Univariate Analysis: Examining individual variables.
• Bivariate Analysis: Examining relationships between two variables.
• Multivariate Analysis: Examining relationships among multiple variables.
• Visualization: Using charts and graphs to uncover patterns.
IV. Machine Learning Fundamentals:
• Supervised Learning:
• Regression: Predicting continuous values (linear regression, polynomial regression).
• Classification: Predicting categories (logistic regression, decision trees, random forests, support vector machines, k-nearest neighbors).
• Model Evaluation Metrics: R-squared, RMSE (regression), accuracy, precision, recall, F1-score, AUC (classification).
• Unsupervised Learning:
• Clustering: Grouping similar data points (k-means, hierarchical clustering).
• Dimensionality Reduction: Reducing the number of features (principal component analysis).
• Model Selection and Evaluation: