- Christophe Spaenjers
Statistical measure showing the development of art prices since a chosen base year. Index series are often represented as graphs, and allow for a comparison with the performance of other assets. An index also enables the measurement of the correlation of art returns with changes in valuations of other investments. Two techniques are commonly used to construct an art price index based on auction transaction data. First, so-called ‘hedonic’ methods use all available sales information to measure changes in quality-adjusted average transaction prices. Second, ‘repeat-sales’ regression models only use price information on artworks for which at least two transactions are observed to estimate the average return in each period....