Integrating big data in the Belgian CPI Meeting of the Group of Experts on Consumer Price Indices Geneva, Switzerland: 7-9 May 2018 Ken Van Loon1, Dorien Roels2 Abstract Statistics Belgium has been using scanner data from supermarkets in the calculation of the CPI since 2015. The applied method is a version of the so-called “dynamic method” - with some adaptations, e.g. SKUs and linking relaunches - using an unweighted chained Jevons index. Currently this method is compared by Statistics Belgium with multilateral methods (GEKS-Törnqvist, Time Product Dummy, Geary-Khamis and augmented Lehr index) using various splicing options with a goal to switch to a multilateral method in 2020. These comparisons will be presented. Apart from using scanner data, Statistics Belgium has also been web scraping data for a number of consumption segments such as consumer electronics, footwear, hotel reservations, second-hand cars, renting of student rooms, … with a goal to integrate these in the CPI by 2020. A comparison of scraped indices and manually collected indices will be given for footwear and hotel reservations. Web scraping also allows to cover new segments, two examples are described: second-hand cars and renting a student room. Scraping makes characteristics information available, therefore hedonic methods can be used for consumer electronics and second-hand cars. Examples of the resulting indices and the applied hedonic method will be described. 1 Statistics Belgium, email:
[email protected]. 2 Statistics Belgium, email:
[email protected]. The views expressed in this paper are those of the authors and do not necessarily reflect the views of Statistics Belgium.