Post #2323

📊Data Analytics Interview Questions With Answers – Part 2👇 1️⃣What is the difference between OLAP and OLTP? - OLAP (Online Analytical Processing): Used for analysis, complex queries, historical data. - OLTP (Online Transaction Processing): Used for day-to-day transactions like insert/update/delete. 2️⃣What are outliers and how do you handle them? Outliers are data points significantly different from others. Handle using: - Removal - Capping - Transformation (e.g., log scale) - Using robust models (e.g., decision trees) 3️⃣What is data normalization? Normalization scales data to bring all variables to a common range (like 0 to 1). Helps improve model performance. 4️⃣What is the difference between inner join and outer join? - Inner Join: Returns only matching rows from both tables. - Outer Join: Returns all rows from one or both tables, filling with NULLs when no match. 5️⃣Explain time series analysis. A method to analyze data points collected or recorded at specific time intervals (e.g., stock prices, sales). 6️⃣What is hypothesis testing? A statistical method to test an assumption about a population parameter using sample data. 7️⃣What are some key challenges in data analytics? - Data quality & cleanliness - Handling large volumes - Data integration from multiple sources - Choosing the right model/technique 8️⃣What is A/B Testing? A/B testing compares two versions of a variable to determine which one performs better (used in product experiments). 9️⃣What’s the role of a dashboard? Dashboards visualize KPIs and metrics in real-time for business monitoring and quick decisions. 🔟How do you ensure data privacy and security? By using encryption, access controls, anonymization, and following compliance standards like GDPR. Tap ❤️ for Part-3!