Scanner data and quality adjustment (original) (raw)

2017

Insee has launched a pilot experiment which aims at introducing scanner data in the French CPI. Started in 2010 with a small set of companies and a small number of industrial food products, the experiment has now reached a larger scale with a daily transmission of data covering 30% of the market. This experiment gives Insee the occasion to review the quality adjustments in the French CPI. Thus, Insee has chosen a strategy of analysis that is mainly based on the same principle as the one applied for the rest of the French CPI: the sample is drawn yearly in the universe of the products in order to reach a certain level of accuracy in the resulting CPI; a two-steps computation is made : the first step consists in computing micro-aggregates while dealing with possible substitutions that occur at the micro-level by the use of adequate price index formulae and the second step consists in the traditional Laspeyres aggregation. The product is followed until it disappears. It is then replace...