Resources
Notes on analysing data well.
Statistics · 9 min read
Understanding Frequency Distributions
How absolute, relative and cumulative frequencies are built, how to choose class widths with Sturges, Scott and Freedman–Diaconis, and why discrete and continuous data need different treatment.
Methods
· 9 min readA Practical Guide to Historical Data Analysis
A working checklist for analysing time-stamped records: data quality checks, missing values, time zones and calendar alignment, fair comparisons between periods of unequal size, selection bias, and the limits of what historical frequencies can tell you.
Statistics
· 8 min readDescriptive Statistics Explained
Mean, median, mode, quantiles, interquartile range and skewness: what each measure captures, how type-7 quantile interpolation works, and how robust each statistic is to outliers, with a fully worked example.
Visualization
· 9 min readVisualizing Time-Series Data
Aggregation, trailing moving averages, seasonality, year-over-year overlays, heatmaps and log scales: how to chart time-stamped data so the picture reflects the data rather than the charting choices, and the dual-axis traps to avoid.
Statistics
· 9 min readInterpreting Variance and Standard Deviation
What variance and standard deviation measure, why sample statistics divide by n − 1, how to compare spread with the coefficient of variation, and what Chebyshev's inequality and the 68–95–99.7 rule can and cannot tell you.