Data Science Cheet sheets (Final stage)
📊 Statistics for Data Science – Cheat Sheet 1. Types of Statistics Descriptive Statistics → Summarizing data (mean, median, mode, variance, std. dev., etc.) Inferential Statistics → Drawing conclusions about a population using sample data (hypothesis testing, confidence intervals). 2. Types of Data Qualitative (Categorical) Nominal → Categories without order (e.g., Gender, Colors). Ordinal → Categories with order (e.g., Ratings: Poor, Average, Good). Quantitative (Numerical) Discrete → Countable (e.g., No. of students). Continuous → Measurable (e.g., Height, Weight). 3. Measures of Central Tendency Mean = Average Median = Middle value (robust to outliers) Mode = Most frequent value 4. Measures of Dispersion Range = Max – Min Variance = Average squared deviation from mean Standard Deviation (σ) = √Variance IQR (Interquartile Range) = Q3 – Q1 Coefficient of Variation (CV) = (Std. Dev. / Mean) × 100 5. Prob...