What Drives the Difference between Online and Official Price Indexes?
a National Bank of Ukraine, Kyiv, Ukraine
b National University of Kyiv-Mohyla Academy, Kyiv, Ukraine
c Swansea University, Swansea, UK

This paper examines the associations between online price indexes and official statistics. First, we generate online CPI component sub-indexes, which are later aggregated to an Online Price CPI. This approach is applied to our unique dataset which contains about 3 million observations of online retail prices for consumer goods in Ukraine’s five largest cities. The data span over the period 2016m1 – 2017m12 and cover about 46% of Ukraine’s Consumer Price Inflation basket. We find that online inflation is generally consistent with official estimates, but the matching capability varies across sub-indexes. Although the differences can partially be explained by poor dataset coverage, we find that online prices may indeed represent new information that is not captured by official statistics.

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Avaliable online 29 March 2018
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Cite as: Faryna, O., Talavera, O., Yukhymenko, T. (2018). What Drives the Difference between Online and Official Price Indexes?. Visnyk of the National Bank of Ukraine, 243, 21-32. https://doi.org/10.26531/vnbu2018.243.021
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