Update README.md

README.md

@@ -4,6 +4,54 @@ Dataset & Analysis by Lipaz Levy
 This project explores how students’ daily habits — including study hours, sleep, social media use, lifestyle factors, mental health, exercise, diet quality, and more — influence their academic performance.
 
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+We used a dataset of **500 students**, each with lifestyle habits, well-being indicators, and exam scores.  
+The goal was to answer:
+
+📌 **How do students’ daily habits affect their exam performance?**
+
+---
+
+# 🧹 Data Cleaning & Preprocessing
+
+Before performing analysis, several preprocessing steps were required to clean and prepare the dataset.
+
+## ✔ 1. Checked for missing values  
+- No missing values were found.
+
+## ✔ 2. Fixed formatting issues  
+- Trimmed spaces from categorical values (“ Yes” → “Yes”).
+
+## ✔ 3. Encoded categorical variables for correlations & regressions  
+Added encoded columns:
+
+- **diet_quality_encoded**  
+  - Poor → 0  
+  - Fair → 1  
+  - Good → 2  
+
+- **internet_quality_encoded**  
+  - Poor → 0  
+  - Average → 1  
+  - Good → 2  
+
+## ✔ 4. Converted columns to numeric  
+Ensured all measurement columns were floats:
+- study_hours_per_day  
+- sleep_hours  
+- social_media_hours  
+- netflix_hours  
+- exercise_frequency  
+- attendance_percentage  
+- exam_score  
+
+## ✔ 5. Dataset shape  
+- **Original:** 500 rows × 16 columns  
+- **After encoding:** 500 rows × 18 columns  
+
+## ✔ 6. Outlier check  
+- All values were within valid human ranges.  
+- No rows were removed.
+
 
 #  **Main Research Question**
 **How do students’ daily habits affect their exam performance?**