Methodology topics
Technical deep-dives on every statistical method and index construction rule we use. Cite-ready for journalists, analysts, and researchers.
- Statistics
Median, percentiles and IQR
Why we publish median and percentiles instead of mean prices, and how to read the IQR for variance signaling.
4 sections - Statistics
Compound Annual Growth Rate (CAGR)
How we annualize price changes across 1, 3, and 5 year windows.
4 sections - Indexes
Volume weighting and index construction
How components contribute to a Bagonomics index: square-root weights, caps, and a chained Laspeyres-style divisor.
4 sections - Statistics
Premium to retail
Definition of premium-to-retail, the country-of-retail convention, and how to interpret negative premium.
4 sections - Quality
Confidence labels
What 'low', 'medium', 'high' confidence on an aggregation means and when to use which.
4 sections