
Learning With Roshan Jha
May 30, 2025 at 03:26 AM
📊 Hypothesis Testing Intuition – Simplified for Everyone!
🔍 Ever wondered how data scientists make decisions based on data instead of assumptions?
Welcome to the world of Hypothesis Testing — the backbone of statistical inference.
🎯 1. One-Sample t-Test
💡 Question: Is the average salary of employees in my company significantly different from the industry average (60,000)?
✅ Use When:
You have one sample and want to compare it to a known population mean.
🎯 2. Two-Sample t-Test (Independent Samples)
💡 Question: Do male and female employees have different average salaries?
✅ Use When:
You want to compare the means of two independent groups.
🎯 3. Paired t-Test
💡 Question: Did our employees' performance improve before vs after training?
✅ Use When:
You compare two related samples (same group at two different times).
🎯 4. ANOVA (Analysis of Variance)
💡 Question: Do sales performance differ across 3 regions — North, South, East?
✅ Use When:
You compare the means of 3 or more groups.
🎯 5. Chi-Square Test
💡 Question: Is there a relationship between customer gender and product preference?
✅ Use When:
You're working with categorical variables to test for association or independence.
🎯 6. Z-Test
💡 Question: Is the average battery life of a new phone is greator than 10 hours (with known population standard deviation)?
✅ Use When:
You know the population standard deviation and sample size is large (n is greator 30).
📌 Bonus: p-value Intuition
p less 0.05 Evidence against the null hypothesis, result is statistically significant
p greator 0.05 Not enough evidence, fail to reject the null