Using consumer price statistics data for regional price comparisons

Abstract

"The calculation of the Consumer Price Index for Germany (CPI) provides comprehensive and detailed information regarding the price development over time every month. However, if differences in the price level across regions in Germany have to be analysed at a given point in time, sufficient information is not available at present. To calculate the consumer price index, different products are selected for price observation in the German regions. Due to these regional differences concerning the product selection, price observations of the consumer price index are only suitable to a limited extent for a spatial price comparison. This study analyses 14 example product types to explore if a sufficient number of price observations remains after an ex-post selection of inter-regionally comparable products. A further subject of the study is the quality adjustment for heterogeneous products of the consumer price statistics. The results of the study show that too few price observations remain in the regional sub-samples for the spatial price comparison after an ex-post selection of comparable products with tight specifications. If product specifications are broadened, the number of available price observations increases. However, then sub-samples are too heterogeneous and prices are not comparable. Theoretically, quality adjustments for heterogeneous products are feasible, but entail a high effort. An application of quality adjustment methods in spatial price comparisons seems only reasonable in areas for which quality adjustment methods are already implemented in consumer price statistics." (Authors' abstract, IAB-Doku) ((en))

Cite article

Behrmann, T., Deml, S. & Linz, S. (2010): Verwendung von Einzeldaten aus der Verbraucherpreisstatistik für regionale Preisvergleiche. In: J. Möller, E. Hohmann & D. Huschka (Hrsg.) (2010): Der weiße Fleck - zur Konzeption und Machbarkeit regionaler Preisindizes (IAB-Bibliothek, 324), p. 11-89.