| 📊 Survey Design & Categorical Data |
Survey construction, frequency tables, relative frequency, cumulative frequency, sorting and filtering, unbiased question design |
| 🎲 Probability Analysis |
Joint probability, conditional probability, contingency tables, probability interpretation, simulation-based testing |
| 📈 Descriptive Statistics |
Mean, median, range, Mean Absolute Deviation (MAD), five-number summary, measures of central tendency and variability |
| 🔍 Data Quality & Preparation |
Completeness assessment, validity checks, formatting consistency, missing values, erroneous data, outlier identification and handling |
| 🔄 Data Manipulation |
Concatenation (row-wise and column-wise), aggregation, datetime variable transformation, categorical encoding (one-hot encoding) |
| 🎯 Sampling & Study Design |
Random sampling, sample size selection, data collection planning, generalizability assessment, cognitive bias identification |
| 📉 Hypothesis Testing & Inference |
P-values, statistical significance, practical significance, sample proportions, inferential research questions |
| 🔗 Correlation & Association |
Pearson's correlation coefficient, scatterplots, association interpretation, interpolation and extrapolation |
| 📐 Linear Regression |
Model fitting, prediction calculations, prediction intervals, R-squared, residual analysis, model evaluation |
| 🌲 Classification |
Decision trees, classification rules, decision boundaries, confusion matrices, performance metrics |
| 🎪 Clustering |
K-means clustering, cluster evaluation (similarity, cardinality, magnitude), segment labeling and prioritization |
| ⏰ Time-Series Analysis |
Temporal patterns, trends, seasonality, moving averages, aggregation by time intervals, time-series narratives |
| 📊 Visualization Design |
Chart selection (bar, pie, histogram, scatterplot, box plot, line), visual highlighting, sequential emphasis, cross-highlighting, explanatory titles |
| 💬 Data Communication |
Problem statements, research questions, data storytelling, narrative structure, big idea statements, calls-to-action, evidence-based claims |