Data Methodology & Sources
How Alt/Finance collects, verifies, and aggregates auction price data for luxury collectibles across 6 asset categories.
Data Sources
Alt/Finance aggregates auction and resale data from 47+ sources worldwide. Our data sources include major international auction houses, regional auction houses, and online marketplaces that specialize in luxury collectibles.
Major Auction Houses
- Christie's
- Sotheby's
- Phillips
- Bonhams
- Heritage Auctions
- Antiquorum
Online Marketplaces & Specialized Platforms
We also collect data from dozens of specialized online auction platforms including Catawiki, LiveAuctioneers, Invaluable, and category-specific marketplaces. This ensures comprehensive coverage across all price points and geographies.
Asset Categories Covered
Alt/Finance tracks auction results across 6 luxury collectibles categories:
Data Collection Process
Our data pipeline runs automatically on a weekly schedule to collect, process, and publish new auction results. Here is an overview of the process:
Collection
Automated pipelines collect new auction results from all tracked sources. Each pipeline is tailored to the specific data format and structure of its source.
Verification
Data quality checks validate each record. Withdrawn lots, buy-ins, and incomplete records are flagged and excluded from price calculations.
Normalization
Brand names, model designations, and categories are standardized. Sale prices are converted to USD using the exchange rate on the date of sale.
Aggregation
Verified records are aggregated by brand, model, and time period. Average prices, year-over-year changes, and other statistics are calculated.
Publication
Updated statistics are published to the website. Individual brand pages, category pages, and search indexes are regenerated weekly.
Price Calculation Methodology
Average Price
The average price displayed on each brand or model page is calculated as the arithmetic mean of all verified completed sales for that item in the specified time period. This includes sales across all auction houses and marketplaces in our database.
Currency Conversion
All prices are converted to US Dollars (USD) using the exchange rate on the date of sale. This ensures accurate cross-border price comparisons and consistent trend analysis.
Year-over-Year Change
The YoY percentage change compares the average price in the current year to the average price in the prior year. This metric helps identify price trends and market momentum.
Exclusions
The following are excluded from price calculations to ensure data integrity:
- Withdrawn lots (items pulled from auction before sale)
- Buy-ins (items that did not meet the reserve price)
- Unverified or disputed transactions
- Private sales without publicly recorded prices
Update Frequency
Data is updated on a weekly basis as new auction results are processed. The "Last Updated" date on each statistics page indicates when that page was last regenerated with the latest available data.
Major auction houses typically publish results within 24-48 hours of a sale. Our pipelines collect these results during the following weekly processing cycle.
Limitations & Disclaimers
While we strive for comprehensive coverage, our data has inherent limitations:
- Private sales and off-market transactions are not included
- Some smaller regional auction houses may not be covered
- Historical data availability varies by category and brand
- Condition grading is not standardized across all sources
All data is provided for informational purposes only and should not be considered financial or investment advice. Past performance does not guarantee future results.
Questions About Our Data?
If you have questions about our methodology, data sources, or would like to report a data discrepancy, please contact us at support@altfndata.com.